Space Station communications and tracking systems modeling and RF link simulation

NASA Technical Reports Server (NTRS)

Tsang, Chit-Sang; Chie, Chak M.; Lindsey, William C.

1986-01-01

In this final report, the effort spent on Space Station Communications and Tracking System Modeling and RF Link Simulation is described in detail. The effort is mainly divided into three parts: frequency division multiple access (FDMA) system simulation modeling and software implementation; a study on design and evaluation of a functional computerized RF link simulation/analysis system for Space Station; and a study on design and evaluation of simulation system architecture. This report documents the results of these studies. In addition, a separate User's Manual on Space Communications Simulation System (SCSS) (Version 1) documents the software developed for the Space Station FDMA communications system simulation. The final report, SCSS user's manual, and the software located in the NASA JSC system analysis division's VAX 750 computer together serve as the deliverables from LinCom for this project effort.

Utility of space transportation system to space communication community: Executive summary

NASA Technical Reports Server (NTRS)

Bronstein, L. M.

1975-01-01

The space transportation system (STS) offers the opportunity for maintaining, and perhaps accelerating, growth of the space communication community. This new launch vehicle service, however, must be obtained at a cost lower than the current expandable launch vehicles cost. A cost competitive STS is defined for geostationary payloads. It is concluded that the STS will be useful to the space communication community, as well as to other geostationary satellite system users, if the proposed recommendations are adapted.

Evaluation of components, subsystems, and networks for high rate, high frequency space communications

NASA Technical Reports Server (NTRS)

Kerczewski, Robert J.; Ivancic, William D.; Zuzek, John E.

1991-01-01

The development of new space communications technologies by NASA has included both commercial applications and space science requirements. At NASA's Lewis Research Center, methods and facilities have been developed for evaluating these new technologies in the laboratory. NASA's Systems Integration, Test and Evaluation (SITE) Space Communication System Simulator is a hardware-based laboratory simulator for evaluating space communications technologies at the component, subsystem, system, and network level, geared toward high frequency, high data rate systems. The SITE facility is well-suited for evaluation of the new technologies required for the Space Exploration Initiative (SEI) and advanced commercial systems. This paper describes the technology developments and evaluation requirements for current and planned commercial and space science programs. Also examined are the capabilities of SITE, the past, present, and planned future configurations of the SITE facility, and applications of SITE to evaluation of SEI technology.

Space Station communications system design and analysis

NASA Technical Reports Server (NTRS)

Ratliff, J. E.

1986-01-01

Attention is given to the methodologies currently being used as the framework within which the NASA Space Station's communications system is to be designed and analyzed. A key aspect of the CAD/analysis system being employed is its potential growth in size and capabilities, since Space Station design requirements will continue to be defined and modified. The Space Station is expected to furnish communications between itself and astronauts on EVA, Orbital Maneuvering Vehicles, Orbital Transfer Vehicles, Space Shuttle orbiters, free-flying spacecraft, coorbiting platforms, and the Space Shuttle's own Mobile Service Center.

Technology developments integrating a space network communications testbed

NASA Technical Reports Server (NTRS)

Kwong, Winston; Jennings, Esther; Clare, Loren; Leang, Dee

2006-01-01

As future manned and robotic space explorations missions involve more complex systems, it is essential to verify, validate, and optimize such systems through simulation and emulation in a low cost testbed environment. The goal of such a testbed is to perform detailed testing of advanced space and ground communications networks, technologies, and client applications that are essential for future space exploration missions. We describe the development of new technologies enhancing our Multi-mission Advanced Communications Hybrid Environment for Test and Evaluation (MACHETE) that enables its integration in a distributed space communications testbed. MACHETE combines orbital modeling, link analysis, and protocol and service modeling to quantify system performance based on comprehensive considerations of different aspects of space missions.

Services, architectures, and protocols for space data systems

NASA Technical Reports Server (NTRS)

Helgert, Hermann J.

1991-01-01

The author presents a comprehensive discussion of three major aspects of the work of the Consultative Committee for Space Data Systems (CCSDS), a worldwide cooperative effort of national space agencies. The author examines the CCSDS space data communications network concept on which the data communications facilities of future advanced orbiting systems will be based. He derives the specifications of an open communications architecture as a reference model for the development of services and protocols that support the transfer of information over space data communications networks. Detailed specifications of the communication services and information transfer protocols that have reached a high degree of maturity and stability are offered. The author also includes a complete list of currently available CCSDS standards and supporting documentation.

User manual of the CATSS system (version 1.0) communication analysis tool for space station

NASA Technical Reports Server (NTRS)

Tsang, C. S.; Su, Y. T.; Lindsey, W. C.

1983-01-01

The Communication Analysis Tool for the Space Station (CATSS) is a FORTRAN language software package capable of predicting the communications links performance for the Space Station (SS) communication and tracking (C & T) system. An interactive software package was currently developed to run on the DEC/VAX computers. The CATSS models and evaluates the various C & T links of the SS, which includes the modulation schemes such as Binary-Phase-Shift-Keying (BPSK), BPSK with Direct Sequence Spread Spectrum (PN/BPSK), and M-ary Frequency-Shift-Keying with Frequency Hopping (FH/MFSK). Optical Space Communication link is also included. CATSS is a C & T system engineering tool used to predict and analyze the system performance for different link environment. Identification of system weaknesses is achieved through evaluation of performance with varying system parameters. System tradeoff for different values of system parameters are made based on the performance prediction.

The deep space network, volume 18. [Deep Space Instrumentation Facility, Ground Communication Facility, and Network Control System

NASA Technical Reports Server (NTRS)

1973-01-01

The objectives, functions, and organization of the Deep Space Network are summarized. The Deep Space Instrumentation Facility, the Ground Communications Facility, and the Network Control System are described.

Facility for the evaluation of space communications and related systems

NASA Technical Reports Server (NTRS)

Kerczewski, Robert J.; Svoboda, James S.; Kachmar, Brian A.

1995-01-01

NASA Lewis Research Center's Communications Projects Branch has developed a facility for the evaluation of space communications systems and related types of systems, called the Advanced Space Communications (ASC) Laboratory. The ASC Lab includes instrumentation, testbed hardware, and experiment control and monitor software for the evaluation of components, subsystems, systems, and networks. The ASC lab has capabilities to perform radiofrequency (RF), microwave, and millimeter-wave characterizations as well as measurements using low, medium, or high data rate digital signals. In addition to laboratory measurements, the ASC Lab also includes integrated satellite ground terminals allowing experimentation and measurements accessing operational satellites through real space links.

Research in space commercialization, technology transfer and communications, vol. 2

NASA Technical Reports Server (NTRS)

Dunn, D. A.; Agnew, C. E.

1983-01-01

Spectrum management, models for evaluating communications systems, and implications of communications regulations for NASA are considered as major parts of communications policy. Marketing LANDSAT products in developing countries, a political systems analysis of LANDSAT, and private financing and operation of the space operations center (space station) are discussed. Investment requirements, risks, government support, and other primary business and management considerations are examined.

Optical communication for space missions

NASA Technical Reports Server (NTRS)

Firtmaurice, M.

1991-01-01

Activities performed at NASA/GSFC (Goddard Space Flight Center) related to direct detection optical communications for space applications are discussed. The following subject areas are covered: (1) requirements for optical communication systems (data rates and channel quality; spatial acquisition; fine tracking and pointing; and transmit point-ahead correction); (2) component testing and development (laser diodes performance characterization and life testing; and laser diode power combining); (3) system development and simulations (The GSFC pointing, acquisition and tracking system; hardware description; preliminary performance analysis; and high data rate transmitter/receiver systems); and (4) proposed flight demonstration of optical communications.

Architecting the Communication and Navigation Networks for NASA's Space Exploration Systems

NASA Technical Reports Server (NTRS)

Bhassin, Kul B.; Putt, Chuck; Hayden, Jeffrey; Tseng, Shirley; Biswas, Abi; Kennedy, Brian; Jennings, Esther H.; Miller, Ron A.; Hudiburg, John; Miller, Dave;

Infrared Free Space Communication - The Autonomous Testing of Free Space Infrared Communication

NASA Technical Reports Server (NTRS)

Heldman, Christopher

2017-01-01

Fiber optics has been a winning player in the game of high-speed communication and data transfer in cable connections. Yet, in free space RF has been the repeated choice of communication medium of the space industry. Investigating the benefits of free space optical communication over radio frequency is worthwhile. An increase in science data rate return capabilities could occur if optical communication is implemented. Optical communication systems also provide efficiencies in power, mass, and volume over RF systems1. Optical communication systems have been demonstrated from a satellite in orbit with the moon to earth, and resulted in the highest data rates ever seen through space (622Mbps)2. Because of these benefits, optical communication is far superior to RF. The HiDRA (High Data Rate Architecture) project is researching Passive Misalignment Mitigation of Dynamic Free Apace Optical Communication Links. The goal of this effort is to enable gigabit per second transmission of data in short range dynamic links (less than 100 meters). In practice this would enhance data rates between sites on the International Space Station with minimal size, weight, and power requirements. This paper will focus on an autonomous code and a hardware setup that will be used to fulfill the next step in the research being conducted. The free space optical communications pointing downfalls will be investigated. This was achieved by creating 5 python programs and a top-level code to automate this test.

Design of low SWaP optical terminals for free space optical communications

NASA Astrophysics Data System (ADS)

Shubert, P.; Cline, A.; McNally, J.; Pierson, R.

2017-02-01

Along with advantages in higher data rates, spectrum contention, and security, free space optical communications can provide size, weight, and power (SWaP) advantages over radio frequency (RF) systems. SWaP is always an issue in space systems and can be critical in applying free space optical communications to small satellite platforms. The system design of small space-based free space optical terminals with Gbps data rates is addressed. System architectures and requirements are defined to ensure the terminals are capable of acquisition, establishment and maintenance of a free space optical communications link. Design trades, identification of blocking technologies, and performance analyses are used to evaluate the practical limitations to terminal SWaP. Small terminal design concepts are developed to establish their practicality and feasibility. Techniques, such as modulation formats and capacity approaching encoding, are considered to mitigate the disadvantages brought by SWaP limitations, and performance as a function of SWaP is evaluated.

77 FR 6949 - Tracking and Data Relay Satellite System (TDRSS) Rates for Non-U.S. Government Customers

Federal Register 2010, 2011, 2012, 2013, 2014

2012-02-10

... Space Telescope. A principal advantage of TDRSS is providing communications services, which previously... instead be placed on the Space Communications and Navigation Program (SCaN) Web site and updated... satellites and ground stations used by NASA for space communications near the Earth. The system was designed...

A systems engineering initiative for NASA's space communications

NASA Technical Reports Server (NTRS)

Hornstein, Rhoda S.; Hei, Donald J., Jr.; Kelly, Angelita C.; Lightfoot, Patricia C.; Bell, Holland T.; Cureton-Snead, Izeller E.; Hurd, William J.; Scales, Charles H.

1993-01-01

In addition to but separate from the Red and Blue Teams commissioned by the NASA Administrator, NASA's Associate Administrator for Space Communications commissioned a Blue Team to review the Office of Space Communications (Code O) Core Program and determine how the program could be conducted faster, better, and cheaper, without compromising safety. Since there was no corresponding Red Team for the Code O Blue Team, the Blue Team assumed a Red Team independent attitude and challenged the status quo. The Blue Team process and results are summarized. The Associate Administrator for Space Communications subsequently convened a special management session to discuss the significance and implications of the Blue Team's report and to lay the groundwork and teamwork for the next steps, including the transition from engineering systems to systems engineering. The methodology and progress toward realizing the Code O Family vision and accomplishing the systems engineering initiative for NASA's space communications are presented.

Transceiver for Space Station Freedom

NASA Technical Reports Server (NTRS)

Fitzmaurice, M.; Bruno, R.

1990-01-01

This paper describes the design of the Laser Communication Transceiver (LCT) system which was planned to be flight tested as an attached payload on Space Station Freedom. The objective in building and flight-testing the LCT is to perform a broad class of tests addressing the critical aspects of space-based optical communications systems, providing a base of experience for applying laser communications technology toward future communications needs. The LCT's functional and performance requirements and capabilities with respect to acquisition, spatial tracking and pointing, communications, and attitude determination are discussed.

Transceiver for Space Station Freedom

NASA Astrophysics Data System (ADS)

Fitzmaurice, M.; Bruno, R.

1990-07-01

This paper describes the design of the Laser Communication Transceiver (LCT) system which was planned to be flight tested as an attached payload on Space Station Freedom. The objective in building and flight-testing the LCT is to perform a broad class of tests addressing the critical aspects of space-based optical communications systems, providing a base of experience for applying laser communications technology toward future communications needs. The LCT's functional and performance requirements and capabilities with respect to acquisition, spatial tracking and pointing, communications, and attitude determination are discussed.

Conceptual communications system design in the 25.25-27.5 and 37.0-40.5 GHz frequency bands

NASA Technical Reports Server (NTRS)

Thompson, Michael W.

1993-01-01

Future space applications are likely to rely heavily on Ka-band frequencies (20-40 GHz) for communications traffic. Many space research activities are now conducted using S-band and X-band frequencies, which are becoming congested and require a degree of pre-coordination. In addition to providing relief from frequency congestion, Ka-band technologies offer potential size, weight, and power savings when compared to lower frequency bands. The use of the 37.0-37.5 and 40.0-40.5 GHz bands for future planetary missions was recently approved at the 1992 World Administrative Radio Conference (WARC-92). WARC-92 also allocated the band 25.25-27.5 GHz to the Intersatellite Service on a primary basis to accommodate Data Relay Satellite return link requirements. Intersatellite links are defined to be between artificial satellites and thus a communication link with the surface of a planetary body, such as the moon, and a relay satellite orbiting that body are not permitted in this frequency band. This report provides information about preliminary communications system concepts for forward and return links for earth-Mars and earth-lunar links using the 37.0-37.5 (return link) and 40.0-40.5 (forward link) GHz frequency bands. In this study we concentrate primarily on a conceptual system for communications between earth and a single lunar surface terminal (LST), and between earth and a single Mars surface terminal (MST). Due to large space losses, these links have the most stringent link requirements for an overall interplanetary system. The earth ground station is assumed to be the Deep Space Network (DSN) using either 34 meter or 70 meter antennas. We also develop preliminary communications concepts for a space-to-space system operating at near 26 GHz. Space-to-space applications can encompass a variety of operating conditions, and we consider several 'typical' scenarios described in more detail later in this report. Among these scenarios are vehicle-to-vehicle communications, vehicle-to-geosyncronous satellite (GEO) communications, and GEO-to-GEO communications. Additional details about both the interplanetary and space-to-space communications systems are provided in an 'expanded' final report which has been submitted to the Tracking and Communications Division (TCD) at the NASA Johnson Space Center.

A Reconfigurable Communications System for Small Spacecraft

NASA Technical Reports Server (NTRS)

Chu, Pong P.; Kifle, Muli

2004-01-01

Two trends of NASA missions are the use of multiple small spacecraft and the development of an integrated space network. To achieve these goals, a robust and agile communications system is needed. Advancements in field programmable gate array (FPGA) technology have made it possible to incorporate major communication and network functionalities in FPGA chips; thus this technology has great potential as the basis for a reconfigurable communications system. This report discusses the requirements of future space communications, reviews relevant issues, and proposes a methodology to design and construct a reconfigurable communications system for small scientific spacecraft.

Cognitive Communications Protocols for SATCOM

DTIC Science & Technology

2017-10-20

both inadvertent Radio Frequency Interference (RFI) and deliberate jammers. Cognitive satellite and space communications strategies based on the... communications protocols for satellite and space communications with possible broad applications in defense, homeland-security as well as consumer...proposed WACR as the basis for future space communication systems that will offer significant benefits to national war‐fighting and peacekeeping

9433 Design Pointing Anomaly. Volume II. Appendices

DTIC Science & Technology

1976-01-30

CALIFORNIA 90278 This final report was submitted by TRW Defense and Space t) Systems Group, One Space Park, Redondo Beach, CA 90278, under Contract F04701-75...C-0257, with the Space and Missile Systems Organization, Deputy for Space Communications Systems , P.O. Box 92960, Worldway Postal Center, Los Angeles...CA 90009. Captain G. D. Nordley, SAMSO/SKD, was the Projcect Officer for Space Communications Systems . This report has been reviewed by the

Deep Space Network equipment performance, reliability, and operations management information system

NASA Technical Reports Server (NTRS)

Cooper, T.; Lin, J.; Chatillon, M.

2002-01-01

The Deep Space Mission System (DSMS) Operations Program Office and the DeepSpace Network (DSN) facilities utilize the Discrepancy Reporting Management System (DRMS) to collect, process, communicate and manage data discrepancies, equipment resets, physical equipment status, and to maintain an internal Station Log. A collaborative effort development between JPL and the Canberra Deep Space Communication Complex delivered a system to support DSN Operations.

Space Shuttle Communications Coverage Analysis for Thermal Tile Inspection

NASA Technical Reports Server (NTRS)

Kroll, Quin D.; Hwu, Shian U.; Upanavage, Matthew; Boster, John P.; Chavez, Mark A.

2009-01-01

The space shuttle ultra-high frequency Space-to-Space Communication System has to provide adequate communication coverage for astronauts who are performing thermal tile inspection and repair on the underside of the space shuttle orbiter (SSO). Careful planning and quantitative assessment are necessary to ensure successful system operations and mission safety in this work environment. This study assesses communication systems performance for astronauts who are working in the underside, non-line-of-sight shadow region on the space shuttle. All of the space shuttle and International Space Station (ISS) transmitting antennas are blocked by the SSO structure. To ensure communication coverage at planned inspection worksites, the signal strength and link margin between the SSO/ISS antennas and the extravehicular activity astronauts, whose line-of-sight is blocked by vehicle structure, was analyzed. Investigations were performed using rigorous computational electromagnetic modeling techniques. Signal strength was obtained by computing the reflected and diffracted fields along the signal propagation paths between transmitting and receiving antennas. Radio frequency (RF) coverage was determined for thermal tile inspection and repair missions using the results of this computation. Analysis results from this paper are important in formulating the limits on reliable communication range and RF coverage at planned underside inspection and repair worksites.

NASA's Use of Commercial Satellite Systems: Concepts and Challenges

NASA Technical Reports Server (NTRS)

Budinger, James M.

1998-01-01

Lewis Research Center's Space Communications Program has a responsibility to investigate, plan for, and demonstrate how NASA Enterprises can use advanced commercial communications services and technologies to satisfy their missions' space communications needs. This presentation looks at the features and challenges of alternative hardware system architecture concepts for providing specific categories of communications services.

GLOBECOM '86 - Global Telecommunications Conference, Houston, TX, Dec. 1-4, 1986, Conference Record. Volumes 1, 2, & 3

NASA Astrophysics Data System (ADS)

Papers are presented on local area networks; formal methods for communication protocols; computer simulation of communication systems; spread spectrum and coded communications; tropical radio propagation; VLSI for communications; strategies for increasing software productivity; multiple access communications; advanced communication satellite technologies; and spread spectrum systems. Topics discussed include Space Station communication and tracking development and design; transmission networks; modulation; data communications; computer network protocols and performance; and coding and synchronization. Consideration is given to free space optical communications systems; VSAT communication networks; network topology design; advances in adaptive filtering echo cancellation and adaptive equalization; advanced signal processing for satellite communications; the elements, design, and analysis of fiber-optic networks; and advances in digital microwave systems.

Compact Deep-Space Optical Communications Transceiver

NASA Technical Reports Server (NTRS)

Roberts, W. Thomas; Charles, Jeffrey R.

2009-01-01

Deep space optical communication transceivers must be very efficient receivers and transmitters of optical communication signals. For deep space missions, communication systems require high performance well beyond the scope of mere power efficiency, demanding maximum performance in relation to the precious and limited mass, volume, and power allocated. This paper describes the opto-mechanical design of a compact, efficient, functional brassboard deep space transceiver that is capable of achieving megabyte-per-second rates at Mars ranges. The special features embodied to enhance the system operability and functionality, and to reduce the mass and volume of the system are detailed. System tests and performance characteristics are described in detail. Finally, lessons learned in the implementation of the brassboard design and suggestions for improvements appropriate for a flight prototype are covered.

Near Sun Free-Space Optical Communications from Space

NASA Technical Reports Server (NTRS)

Biswas, Abhijit; Khatri, F.; Boroson, D.

2006-01-01

Free-space optical communications offers expanded data return capacity, from probes distributed throughout the solar system and beyond. Space-borne and Earth-based optical transceivers used for communicating optically, will periodically encounter near Sun pointing. This will result in an increase in the scattered background light flux, often contributing to degraded link performance. The varying duration of near Sun pointing link operations relative to the location of space-probes, is discussed in this paper. The impact of near Sun pointing on link performance for a direct detection photon-counting communications system is analyzed for both ground- and space-based Earth receivers. Finally, impact of near Sun pointing on spaceborne optical transceivers is discussed.

Architecting Communication Network of Networks for Space System of Systems

NASA Technical Reports Server (NTRS)

Bhasin, Kul B.; Hayden, Jeffrey L.

2008-01-01

The National Aeronautics and Space Administration (NASA) and the Department of Defense (DoD) are planning Space System of Systems (SoS) to address the new challenges of space exploration, defense, communications, navigation, Earth observation, and science. In addition, these complex systems must provide interoperability, enhanced reliability, common interfaces, dynamic operations, and autonomy in system management. Both NASA and the DoD have chosen to meet the new demands with high data rate communication systems and space Internet technologies that bring Internet Protocols (IP), routers, servers, software, and interfaces to space networks to enable as much autonomous operation of those networks as possible. These technologies reduce the cost of operations and, with higher bandwidths, support the expected voice, video, and data needed to coordinate activities at each stage of an exploration mission. In this paper, we discuss, in a generic fashion, how the architectural approaches and processes are being developed and used for defining a hypothetical communication and navigation networks infrastructure to support lunar exploration. Examples are given of the products generated by the architecture development process.

Space Station communications and tracking system

NASA Technical Reports Server (NTRS)

Dietz, Reinhold H.

1987-01-01

A comprehensive description of the existing Space Station communications and tracking system requirements, architecture, and design concepts is provided. Areas which will require innovative solutions to provide cost-effective flight systems are emphasized. Among these are the space-to-space links, the differential global positioning system for determining relative position with free-flying vehicles, multitarget radar, packet/isochronous signal processing, and laser docking systems. In addition, the importance of advanced development, tests, and analyses is summarized.

Operational Concepts for a Generic Space Exploration Communication Network Architecture

NASA Technical Reports Server (NTRS)

Ivancic, William D.; Vaden, Karl R.; Jones, Robert E.; Roberts, Anthony M.

2015-01-01

This document is one of three. It describes the Operational Concept (OpsCon) for a generic space exploration communication architecture. The purpose of this particular document is to identify communication flows and data types. Two other documents accompany this document, a security policy profile and a communication architecture document. The operational concepts should be read first followed by the security policy profile and then the architecture document. The overall goal is to design a generic space exploration communication network architecture that is affordable, deployable, maintainable, securable, evolvable, reliable, and adaptable. The architecture should also require limited reconfiguration throughout system development and deployment. System deployment includes: subsystem development in a factory setting, system integration in a laboratory setting, launch preparation, launch, and deployment and operation in space.

Space shuttle Ku-band integrated rendezvous radar/communications system study

NASA Technical Reports Server (NTRS)

1976-01-01

The results are presented of work performed on the Space Shuttle Ku-Band Integrated Rendezvous Radar/Communications System Study. The recommendations and conclusions are included as well as the details explaining the results. The requirements upon which the study was based are presented along with the predicted performance of the recommended system configuration. In addition, shuttle orbiter vehicle constraints (e.g., size, weight, power, stowage space) are discussed. The tradeoffs considered and the operation of the recommended configuration are described for an optimized, integrated Ku-band radar/communications system. Basic system tradeoffs, communication design, radar design, antenna tradeoffs, antenna gimbal and drive design, antenna servo design, and deployed assembly packaging design are discussed. The communications and radar performance analyses necessary to support the system design effort are presented. Detailed derivations of the communications thermal noise error, the radar range, range rate, and angle tracking errors, and the communications transmitter distortion parameter effect on crosstalk between the unbalanced quadriphase signals are included.

Technology forecasting for space communication. [analysis of systems for application to Spacecraft Data and Tracking Network

NASA Technical Reports Server (NTRS)

1973-01-01

A study was conducted to determine techniques for application to space communication. The subjects considered are as follows: (1) optical communication systems, (2) laser communications for data acquisition networks, (3) spacecraft data rate requirements, (4) telemetry, command, and data handling, (5) spacecraft tracking and data network antenna and preamplifier cost tradeoff study, and (6) spacecraft communication terminal evaluation.

Modeling and analysis of selected space station communications and tracking subsystems

NASA Technical Reports Server (NTRS)

Richmond, Elmer Raydean

1993-01-01

The Communications and Tracking System on board Space Station Freedom (SSF) provides space-to-ground, space-to-space, audio, and video communications, as well as tracking data reception and processing services. Each major category of service is provided by a communications subsystem which is controlled and monitored by software. Among these subsystems, the Assembly/Contingency Subsystem (ACS) and the Space-to-Ground Subsystem (SGS) provide communications with the ground via the Tracking and Data Relay Satellite (TDRS) System. The ACS is effectively SSF's command link, while the SGS is primarily intended as the data link for SSF payloads. The research activities of this project focused on the ACS and SGS antenna management algorithms identified in the Flight System Software Requirements (FSSR) documentation, including: (1) software modeling and evaluation of antenna management (positioning) algorithms; and (2) analysis and investigation of selected variables and parameters of these antenna management algorithms i.e., descriptions and definitions of ranges, scopes, and dimensions. In a related activity, to assist those responsible for monitoring the development of this flight system software, a brief summary of software metrics concepts, terms, measures, and uses was prepared.

Performance analysis of fiber-based free-space optical communications with coherent detection spatial diversity.

PubMed

Li, Kangning; Ma, Jing; Tan, Liying; Yu, Siyuan; Zhai, Chao

2016-06-10

The performances of fiber-based free-space optical (FSO) communications over gamma-gamma distributed turbulence are studied for multiple aperture receiver systems. The equal gain combining (EGC) technique is considered as a practical scheme to mitigate the atmospheric turbulence. Bit error rate (BER) performances for binary-phase-shift-keying-modulated coherent detection fiber-based free-space optical communications are derived and analyzed for EGC diversity receptions through an approximation method. To show the net diversity gain of a multiple aperture receiver system, BER performances of EGC are compared with a single monolithic aperture receiver system with the same total aperture area (same average total incident optical power on the aperture surface) for fiber-based free-space optical communications. The analytical results are verified by Monte Carlo simulations. System performances are also compared for EGC diversity coherent FSO communications with or without considering fiber-coupling efficiencies.

Free-space laser communication technologies III; Proceedings of the Meeting, Los Angeles, CA, Jan. 21, 22, 1991

NASA Technical Reports Server (NTRS)

Begley, David L. (Editor); Seery, Bernard D. (Editor)

1991-01-01

The present volume on free-space laser communication technologies discusses system analysis, performance, and applications, pointing, acquisition, and tracking in beam control, laboratory demonstration systems, and transmitter and critical component technologies. Attention is given to a space station laser communication transceiver, meeting intersatellite links mission requirements by an adequate optical terminal design, an optical approach to proximity-operations communications for Space Station Freedom, and optical space-to-ground link availability assessment and diversity requirements. Topics addressed include nonmechanical steering of laser beams by multiple aperture antennas, a free-space simulator for laser transmission, heterodyne acquisition and tracking in a free-space diode laser link, and laser terminal attitude determination via autonomous star tracking. Also discussed are stability considerations in relay lens design for optical communications, liquid crystals for lasercom applications, and narrowband optical interference filters.

Software Defined Radio Architecture Contributions to Next Generation Space Communications

NASA Technical Reports Server (NTRS)

Kacpura, Thomas J.; Eddy, Wesley M.; Smith, Carl R.; Liebetreu, John

2015-01-01

Space communications architecture concepts, comprising the elements of the system, the interactions among them, and the principles that govern their development, are essential factors in developing National Aeronautics and Space Administration (NASA) future exploration and science missions. Accordingly, vital architectural attributes encompass flexibility, the extensibility to insert future capabilities, and to enable evolution to provide interoperability with other current and future systems. Space communications architectures and technologies for this century must satisfy a growing set of requirements, including those for Earth sensing, collaborative observation missions, robotic scientific missions, human missions for exploration of the Moon and Mars where surface activities require supporting communications, and in-space observatories for observing the earth, as well as other star systems and the universe. An advanced, integrated, communications infrastructure will enable the reliable, multipoint, high-data-rate capabilities needed on demand to provide continuous, maximum coverage for areas of concentrated activity. Importantly, the cost/value proposition of the future architecture must be an integral part of its design; an affordable and sustainable architecture is indispensable within anticipated future budget environments. Effective architecture design informs decision makers with insight into the capabilities needed to efficiently satisfy the demanding space-communication requirements of future missions and formulate appropriate requirements. A driving requirement for the architecture is the extensibility to address new requirements and provide low-cost on-ramps for new capabilities insertion, ensuring graceful growth as new functionality and new technologies are infused into the network infrastructure. In addition to extensibility, another key architectural attribute of the space communication equipment's interoperability with other NASA communications systems, as well as those communications and navigation systems operated by international space agencies and civilian and government agencies. In this paper, we review the philosophies, technologies, architectural attributes, mission services, and communications capabilities that form the structure of candidate next-generation integrated communication architectures for space communications and navigation. A key area that this paper explores is from the development and operation of the software defined radio for the NASA Space Communications and Navigation (SCaN) Testbed currently on the International Space Station (ISS). Evaluating the lessons learned from development and operation feed back into the communications architecture. Leveraging the reconfigurability provides a change in the way that operations are done and must be considered. Quantifying the impact on the NASA Space Telecommunications Radio System (STRS) software defined radio architecture provides feedback to keep the standard useful and up to date. NASA is not the only customer of these radios. Software defined radios are developed for other applications, and taking advantage of these developments promotes an architecture that is cost effective and sustainable. Developments in the following areas such as an updated operating environment, higher data rates, networking and security can be leveraged. The ability to sustain an architecture that uses radios for multiple markets can lower costs and keep new technology infused.

Systems and methods for free space optical communication

DOEpatents

Harper, Warren W [Benton City, WA; Aker, Pamela M [Richland, WA; Pratt, Richard M [Richland, WA

2011-05-10

Free space optical communication methods and systems, according to various aspects are described. The methods and systems are characterized by transmission of data through free space with a digitized optical signal acquired using wavelength modulation, and by discrimination between bit states in the digitized optical signal using a spectroscopic absorption feature of a chemical substance.

Research in space commercialization, technology transfer, and communications, volume 2

NASA Technical Reports Server (NTRS)

Dunn, D. A.; Agnew, C. E.

1983-01-01

Spectrum management, models for evaluating communication systems, the communications regulatory environment, expert prediction and consensus, remote sensing, and manned space operations research are discussed.

Atmospheric free-space coherent optical communications with adaptive optics

NASA Astrophysics Data System (ADS)

Ting, Chueh; Zhang, Chengyu; Yang, Zikai

2017-02-01

Free-space coherent optical communications have a potential application to offer last mile bottleneck solution in future local area networks (LAN) because of their information carrier, information security and license-free status. Coherent optical communication systems using orthogonal frequency division multiplexing (OFDM) digital modulation are successfully demonstrated in a long-haul tens Giga bits via optical fiber, but they are not yet available in free space due to atmospheric turbulence-induced channel fading. Adaptive optics is recognized as a promising technology to mitigate the effects of atmospheric turbulence in free-space optics. In this paper, a free-space coherent optical communication system using an OFDM digital modulation scheme and adaptive optics (FSO OFDM AO) is proposed, a Gamma-Gamma distribution statistical channel fading model for the FSO OFDM AO system is examined, and FSO OFDM AO system performance is evaluated in terms of bit error rate (BER) versus various propagation distances.

High data rate modem simulation for the space station multiple-access communications system

NASA Technical Reports Server (NTRS)

Horan, Stephen

1987-01-01

The communications system for the space station will require a space based multiple access component to provide communications between the space based program elements and the station. A study was undertaken to investigate two of the concerns of this multiple access system, namely, the issues related to the frequency spectrum utilization and the possibilities for higher order (than QPSK) modulation schemes for use in possible modulators and demodulators (modems). As a result of the investigation, many key questions about the frequency spectrum utilization were raised. At this point, frequency spectrum utilization is seen as an area requiring further work. Simulations were conducted using a computer aided communications system design package to provide a straw man modem structure to be used for both QPSK and 8-PSK channels.

Analysis of CPolSK-based FSO system working in space-to-ground channel

NASA Astrophysics Data System (ADS)

Su, Yuwei; Sato, Takuro

2018-03-01

In this article, the transmission performance of a circle polarization shift keying (CPolSK)-based free space optical (FSO) system working in space-to-ground channel is analyzed. Formulas describing the optical polarization distortion caused by the atmospheric turbulence and the communication qualities in terms of signal-to-noise-ratio (SNR), bit-error-ratio (BER) and outage probability of the proposed system are derived. Based on the Stokes parameters data measured by a Japanese optical communication satellite, we evaluate the space-to-ground FSO link and simulate the system performance under a varying regime of turbulence strength. The proposed system provides a more efficient way to compensate scintillation effects in a comparison with the on-off-keying (OOK)-based FSO system. These results are useful to the designing and evaluating of a deep space FSO communication system.

Overview of NASA communications infrastructure

NASA Technical Reports Server (NTRS)

Arnold, Ray J.; Fuechsel, Charles

1991-01-01

The infrastructure of NASA communications systems for effecting coordination across NASA offices and with the national and international research and technological communities is discussed. The offices and networks of the communication system include the Office of Space Science and Applications (OSSA), which manages all NASA missions, and the Office of Space Operations, which furnishes communication support through the NASCOM, the mission critical communications support network, and the Program Support Communications network. The NASA Science Internet was established by OSSA to centrally manage, develop, and operate an integrated computer network service dedicated to NASA's space science and application research. Planned for the future is the National Research and Education Network, which will provide communications infrastructure to enhance science resources at a national level.

Integrated source and channel encoded digital communication system design study. [for space shuttles

NASA Technical Reports Server (NTRS)

Huth, G. K.

1976-01-01

The results of several studies Space Shuttle communication system are summarized. These tasks can be divided into the following categories: (1) phase multiplexing for two- and three-channel data transmission, (2) effects of phase noise on the performance of coherent communication links, (3) analysis of command system performance, (4) error correcting code tradeoffs, (5) signal detection and angular search procedure for the shuttle Ku-band communication system, and (6) false lock performance of Costas loop receivers.

The aero optics effect on near space laser communication optical system

NASA Astrophysics Data System (ADS)

Hu, Yuan; Fu, Yuegang; Jiang, Huilin

2013-08-01

With the developing of the space laser communication link, the performance index including higher transfer speed, extending transfer distance, and environmental adaptability, all ask the system accuracy and indexes improving. Special the developing near space platform, its environmental is extremes, the near space drone and other airplane flight speed is very quickly from the subsonic to supersonic. The aero optics effect caused by high speed will generate a thin turbulent air layer. It affects the performance of laser communication optical system by laser light vibration, deviation and so on, further more affects the performance of laser communication system working performance, even can't communication. Therefore, for achieving optical system indexes, we need do more research in optical system near space aero optics environmental adaptability. In this paper, near space link environmental characteristic are researched. And on the base of the aero optics theory, computer simulating method is applied to analyze the relationship among the altitude, the flight speed and the image dispersion. The result shows that, the aero optics effect cannot be ignored when the terminal is in low altitude or is moving with supersonic speed. The effect must be taken into considered from overall design. The result will provide the basis of research design.

Study and design of laser communications system for space shuttle

NASA Technical Reports Server (NTRS)

1973-01-01

The design, development and operation are described of the laser communications system developed for potential space shuttle application. A brief study was conducted to identify the need, if any, for narrow bandwidth space-to-space communication on the shuttle vehicles. None have been specifically identified that could not be accommodated with existing equipments. The key technical features developed in this hardware are the conically scanned tracker for optimized track while communicating with a single detector, and the utilization of a common optical carrier frequency for both transmission and detection. This latter feature permits a multiple access capability so that several transceivers can communicate with one another. The conically scanned tracker technique allows the received signal energy to be efficiently divided between the tracking and communications functions within a common detector.

An Optical Receiver Post Processing System for the Integrated Radio and Optical Communications Software Defined Radio Test Bed

NASA Technical Reports Server (NTRS)

Nappier, Jennifer M.; Tokars, Roger P.; Wroblewski, Adam C.

2016-01-01

The Integrated Radio and Optical Communications (iROC) project at the National Aeronautics and Space Administrations (NASA) Glenn Research Center is investigating the feasibility of a hybrid radio frequency (RF) and optical communication system for future deep space missions. As a part of this investigation, a test bed for a radio frequency (RF) and optical software defined radio (SDR) has been built. Receivers and modems for the NASA deep space optical waveform are not commercially available so a custom ground optical receiver system has been built. This paper documents the ground optical receiver, which is used in order to test the RF and optical SDR in a free space optical communications link.

An Optical Receiver Post-Processing System for the Integrated Radio and Optical Communications Software Defined Radio Test Bed

NASA Technical Reports Server (NTRS)

Nappier, Jennifer M.; Tokars, Roger P.; Wroblewski, Adam C.

2016-01-01

The Integrated Radio and Optical Communications (iROC) project at the National Aeronautics and Space Administration's (NASA) Glenn Research Center is investigating the feasibility of a hybrid radio frequency (RF) and optical communication system for future deep space missions. As a part of this investigation, a test bed for a radio frequency (RF) and optical software defined radio (SDR) has been built. Receivers and modems for the NASA deep space optical waveform are not commercially available so a custom ground optical receiver system has been built. This paper documents the ground optical receiver, which is used in order to test the RF and optical SDR in a free space optical communications link.

Security Policy for a Generic Space Exploration Communication Network Architecture

NASA Technical Reports Server (NTRS)

Ivancic, William D.; Sheehe, Charles J.; Vaden, Karl R.

2016-01-01

This document is one of three. It describes various security mechanisms and a security policy profile for a generic space-based communication architecture. Two other documents accompany this document- an Operations Concept (OpsCon) and a communication architecture document. The OpsCon should be read first followed by the security policy profile described by this document and then the architecture document. The overall goal is to design a generic space exploration communication network architecture that is affordable, deployable, maintainable, securable, evolvable, reliable, and adaptable. The architecture should also require limited reconfiguration throughout system development and deployment. System deployment includes subsystem development in a factory setting, system integration in a laboratory setting, launch preparation, launch, and deployment and operation in space.

Development of the Free-space Optical Communications Analysis Software (FOCAS)

NASA Technical Reports Server (NTRS)

Jeganathan, M.; Mecherle, G.; Lesh, J.

1998-01-01

The Free-space Optical Communications Analysis Software (FOCAS) was developed at the Jet Propulsion Laboratory (JPL) to provide mission planners, systems engineers and communications engineers with an easy to use tool to analyze optical communications link.

Technology Developments Integrating a Space Network Communications Testbed

NASA Technical Reports Server (NTRS)

Kwong, Winston; Jennings, Esther; Clare, Loren; Leang, Dee

2006-01-01

As future manned and robotic space explorations missions involve more complex systems, it is essential to verify, validate, and optimize such systems through simulation and emulation in a low cost testbed environment. The goal of such a testbed is to perform detailed testing of advanced space and ground communications networks, technologies, and client applications that are essential for future space exploration missions. We describe the development of new technologies enhancing our Multi-mission Advanced Communications Hybrid Environment for Test and Evaluation (MACHETE) that enable its integration in a distributed space communications testbed. MACHETE combines orbital modeling, link analysis, and protocol and service modeling to quantify system performance based on comprehensive considerations of different aspects of space missions. It can simulate entire networks and can interface with external (testbed) systems. The key technology developments enabling the integration of MACHETE into a distributed testbed are the Monitor and Control module and the QualNet IP Network Emulator module. Specifically, the Monitor and Control module establishes a standard interface mechanism to centralize the management of each testbed component. The QualNet IP Network Emulator module allows externally generated network traffic to be passed through MACHETE to experience simulated network behaviors such as propagation delay, data loss, orbital effects and other communications characteristics, including entire network behaviors. We report a successful integration of MACHETE with a space communication testbed modeling a lunar exploration scenario. This document is the viewgraph slides of the presentation.

Reference earth orbital research and applications investigations (blue book). Volume 5: Communications/navigation

NASA Technical Reports Server (NTRS)

1971-01-01

The design and development of a communications/navigation facility for operation aboard space stations and space shuttles are discussed. The objectives of the facility are as follows: (1) to develop and demonstrate satellite and spacecraft technology applicable to space communications, navigation, and traffic control, (2) to optimize the use of the electromagnetic spectrum for communications and navigation satellite systems, and (3) to provide fundamental understanding of the space communications and navigation sciences to permit application of this discipline to government and industry.

Tyurin in Zvezda with communication system

NASA Image and Video Library

2007-02-24

ISS014-E-14765 (24 Feb. 2007) --- Cosmonaut Mikhail Tyurin, Expedition 14 flight engineer representing Russia's Federal Space Agency, uses a communication system in the Zvezda Service Module of the International Space Station.

Toward a Dynamically Reconfigurable Computing and Communication System for Small Spacecraft

NASA Technical Reports Server (NTRS)

Kifle, Muli; Andro, Monty; Tran, Quang K.; Fujikawa, Gene; Chu, Pong P.

2003-01-01

Future science missions will require the use of multiple spacecraft with multiple sensor nodes autonomously responding and adapting to a dynamically changing space environment. The acquisition of random scientific events will require rapidly changing network topologies, distributed processing power, and a dynamic resource management strategy. Optimum utilization and configuration of spacecraft communications and navigation resources will be critical in meeting the demand of these stringent mission requirements. There are two important trends to follow with respect to NASA's (National Aeronautics and Space Administration) future scientific missions: the use of multiple satellite systems and the development of an integrated space communications network. Reconfigurable computing and communication systems may enable versatile adaptation of a spacecraft system's resources by dynamic allocation of the processor hardware to perform new operations or to maintain functionality due to malfunctions or hardware faults. Advancements in FPGA (Field Programmable Gate Array) technology make it possible to incorporate major communication and network functionalities in FPGA chips and provide the basis for a dynamically reconfigurable communication system. Advantages of higher computation speeds and accuracy are envisioned with tremendous hardware flexibility to ensure maximum survivability of future science mission spacecraft. This paper discusses the requirements, enabling technologies, and challenges associated with dynamically reconfigurable space communications systems.

Concepts for image management and communication system for space vehicle health management

NASA Astrophysics Data System (ADS)

Alsafadi, Yasser; Martinez, Ralph

On a space vehicle, the Crew Health Care System will handle minor accidents or illnesses immediately, thereby eliminating the necessity of early mission termination or emergency rescue. For practical reasons, only trained personnel with limited medical experience can be available on space vehicles to render preliminary health care. There is the need to communicate with medical experts at different locations on earth. Interplanetary Image Management and Communication System (IIMACS) will be a bridge between worlds and deliver medical images acquired in space to physicians at different medical centers on earth. This paper discusses the implementation of IIMACS by extending the Global Picture Archiving and Communication System (GPACS) being developed to interconnect medical centers on earth. Furthermore, this paper explores system requirements of IIMACS and different user scenarios. Our conclusion is that IIMACS is feasible using the maturing technology base of GPACS.

Ultramicrowave communications system, phase 3

NASA Technical Reports Server (NTRS)

1981-01-01

The ultramicrowave communications system program investigated the feasibility of a solid state system that meets the projected space to space requirements, while using the advantages of the 100 to 200 GHz band. The program successfully demonstrated a laboratory model of a high frequency communications system operating between 100 to 200 GHz. In the process, vendor claims for performance specifications of discrete components were evaluated, and a window was provided into system design and integration problems.

The space shuttle payload planning working groups. Volume 6: Communications and navigation

NASA Technical Reports Server (NTRS)

1973-01-01

The findings of the Communications and Navigation working group of the space shuttle payload planning activity are presented. The basic goals to be accomplished are to increase the use of space systems and to develop new space capabilities for providing communication and navigation services to the user community in the 1980 time period. Specific experiments to be conducted for improving space communication and navigation capabilities are defined. The characteristics of the experimental equipment required to accomplish the mission are discussed.

Technology, Data Bases and System Analysis for Space-to-Ground Optical Communications

NASA Technical Reports Server (NTRS)

Lesh, James

1995-01-01

Optical communications is becoming an ever-increasingly important option for designers of space-to- ground communications links, whether it be for government or commercial applications. In this paper the technology being developed by NASA for use in space-to-ground optical communications is presented. Next, a program which is collecting a long term data base of atmospheric visibility statistics for optical propagation through the atmosphere will be described. Finally, a methodology for utilizing the statistics of the atmospheric data base in the analysis of space-to-ground links will be presented. This methodology takes into account the effects of station availability, is useful when comparing optical communications with microwave systems, and provides a rationale establishing the recommended link margin.

Evaluation of the communication quality of free-space laser communication based on the power-in-the-bucket method.

PubMed

Yin, Xianghui; Wang, Rui; Wang, Shaoxin; Wang, Yukun; Jin, Chengbin; Cao, Zhaoliang; Xuan, Li

2018-02-01

Atmospheric turbulence seriously affects the quality of free-space laser communication. The Strehl ratio (SR) is used to evaluate the effect of atmospheric turbulence on the receiving energy of free-space laser communication systems. However, the SR method does not consider the area of the laser-receiving end face. In this study, the power-in-the-bucket (PIB) method is demonstrated to accurately evaluate the effect of turbulence on the receiving energy. A theoretical equation is first obtained to calculate PIB. Simulated and experimental validations are then performed to verify the effectiveness of the theoretical equation. This work may provide effective guidance for the design and evaluation of free-space laser communication systems.

Algorithm for Cosmic Noise Suppression in Free Space Optical Communications

NASA Astrophysics Data System (ADS)

Yuvaraj, George; Himani Sharma, Goyal, Dr.

2017-08-01

This article describes an algorithm to reduce cosmic noise in free space optical communication system. This method is intended to increase communication system’s performance and to increase the sustainability of the communication system by means of image processing technique. Apart from these, methods employed in testing the model are also presented for the communication system that uses either terrestrial or extraterrestrial medium to propagate message using optics or visible light without considering environmental impact that is turbulence, atmospheric absorption, beam dispersion and light intensity on its performance.

Space-Based Reconfigurable Software Defined Radio Test Bed Aboard International Space Station

NASA Technical Reports Server (NTRS)

Reinhart, Richard C.; Lux, James P.

2014-01-01

The National Aeronautical and Space Administration (NASA) recently launched a new software defined radio research test bed to the International Space Station. The test bed, sponsored by the Space Communications and Navigation (SCaN) Office within NASA is referred to as the SCaN Testbed. The SCaN Testbed is a highly capable communications system, composed of three software defined radios, integrated into a flight system, and mounted to the truss of the International Space Station. Software defined radios offer the future promise of in-flight reconfigurability, autonomy, and eventually cognitive operation. The adoption of software defined radios offers space missions a new way to develop and operate space transceivers for communications and navigation. Reconfigurable or software defined radios with communications and navigation functions implemented in software or VHDL (Very High Speed Hardware Description Language) provide the capability to change the functionality of the radio during development or after launch. The ability to change the operating characteristics of a radio through software once deployed to space offers the flexibility to adapt to new science opportunities, recover from anomalies within the science payload or communication system, and potentially reduce development cost and risk by adapting generic space platforms to meet specific mission requirements. The software defined radios on the SCaN Testbed are each compliant to NASA's Space Telecommunications Radio System (STRS) Architecture. The STRS Architecture is an open, non-proprietary architecture that defines interfaces for the connections between radio components. It provides an operating environment to abstract the communication waveform application from the underlying platform specific hardware such as digital-to-analog converters, analog-to-digital converters, oscillators, RF attenuators, automatic gain control circuits, FPGAs, general-purpose processors, etc. and the interconnections among different radio components.

The Telecommunications and Data Acquisition Report

NASA Technical Reports Server (NTRS)

Yuen, Joseph H. (Editor)

1993-01-01

This quarterly publication provides archival reports on developments in programs managed by JPL's Office of Telecommunications and Data Acquisition (TDA). In space communications, radio navigation, radio science, and ground-based radio and radar astronomy, it reports on activities of the Deep Space Network (DSN) in planning, supporting research and technology, implementation, and operations. Also included are standards activity at JPL for space data and information systems and reimbursable DSN work performed for other space agencies through NASA. The papers included in this document cover satellite tracking and ground-based navigation, spacecraft-ground communications, and optical communication systems for the Deep Space Network.

Economic benefits of the Space Station to commercial communication satellite operators

NASA Technical Reports Server (NTRS)

Price, Kent M.; Dixson, John E.; Weyandt, Charles J.

1987-01-01

The economic and financial aspects of newly defined space-based activities, procedures, and operations (APOs) and associated satellite system designs are presented that have the potential to improve economic performance of future geostationary communications satellites. Launch insurance, launch costs, and the economics of APOs are examined. Retrieval missions and various Space Station scenarios are addressed. The potential benefits of the new APOs to the commercial communications satellite system operator are quantified.

Executive summary. [application of laser oriented and radio frequency techniques for space communication

NASA Technical Reports Server (NTRS)

1973-01-01

The scope of Technology Forecasting for Space Communications is very wide, covering virtually every technology that can directly or indirectly affect space communications. The assigned effort, however, was directed toward a series of studies which individually examined important aspects of space communications and which collectively was interrelated. The contributions of the individual tasks and their interrelationship are indicated. The total effort of the tasks was fairly evenly divided between laser oriented and radio frequency tasks. The investigations show that laser communications have a current state of the art which would allow operational systems to be implemented in the 1975 to 1980 time frame. Further, these systems, when operated over ranges in the order of synchronous ranges (42,000 km)and transmitting data rates of 10 to the 8th power 10 to the 9th power bits per second will have a smaller total weight impact on a spacecraft than do radio systems.

SDR/STRS Flight Experiment and the Role of SDR-Based Communication and Navigation Systems

NASA Technical Reports Server (NTRS)

Reinhart, Richard C.

2008-01-01

This presentation describes an open architecture SDR (software defined radio) infrastructure, suitable for space-based radios and operations, entitled Space Telecommunications Radio System (STRS). SDR technologies will endow space and planetary exploration systems with dramatically increased capability, reduced power consumption, and less mass than conventional systems, at costs reduced by vigorous competition, hardware commonality, dense integration, minimizing the impact of parts obsolescence, improved interoperability, and software re-use. To advance the SDR architecture technology and demonstrate its applicability in space, NASA is developing a space experiment of multiple SDRs each with various waveforms to communicate with NASA s TDRSS satellite and ground networks, and the GPS constellation. An experiments program will investigate S-band and Ka-band communications, navigation, and networking technologies and operations.

Secure free-space optical communication system based on data fragmentation multipath transmission technology.

PubMed

Huang, Qingchao; Liu, Dachang; Chen, Yinfang; Wang, Yuehui; Tan, Jun; Chen, Wei; Liu, Jianguo; Zhu, Ninghua

2018-05-14

A secure free-space optical (S-FSO) communication system based on data fragmentation multipath transmission (DFMT) scheme is proposed and demonstrated for enhancing the security of FSO communications. By fragmenting the transmitted data and simultaneously distributing data fragments into different atmospheric channels, the S-FSO communication system can protect confidential messages from being eavesdropped effectively. A field experiment of S-FSO communication between two buildings has been successfully undertaken, and the experiment results demonstrate the feasibility of the scheme. The transmission distance is 50m and the maximum throughput is 1 Gb/s. We also established a theoretical model to analysis the security performance of the S-FSO communication system. To the best of our knowledge, this is the first application of DFMT scheme in FSO communication system.

The Deep Space Network. [tracking and communication functions and facilities

NASA Technical Reports Server (NTRS)

1974-01-01

The objectives, functions, and organization of the Deep Space Network are summarized. The Deep Space Instrumentation Facility, the Ground Communications Facility, and the Network Control System are described.

Spacecraft Multiple Array Communication System Performance Analysis

NASA Technical Reports Server (NTRS)

Hwu, Shian U.; Desilva, Kanishka; Sham, Catherine C.

2010-01-01

The Communication Systems Simulation Laboratory (CSSL) at the NASA Johnson Space Center is tasked to perform spacecraft and ground network communication system simulations, design validation, and performance verification. The CSSL has developed simulation tools that model spacecraft communication systems and the space and ground environment in which the tools operate. In this paper, a spacecraft communication system with multiple arrays is simulated. Multiple array combined technique is used to increase the radio frequency coverage and data rate performance. The technique is to achieve phase coherence among the phased arrays to combine the signals at the targeting receiver constructively. There are many technical challenges in spacecraft integration with a high transmit power communication system. The array combining technique can improve the communication system data rate and coverage performances without increasing the system transmit power requirements. Example simulation results indicate significant performance improvement can be achieved with phase coherence implementation.

Demonstration of a High-Efficiency Free-Space Optical Communications Link

NASA Technical Reports Server (NTRS)

Birnbaum, Kevin; Farr, William; Gin, Jonathan; Moision, Bruce; Quirk, Kevin; Wright, Malcolm

2009-01-01

In this paper we discuss recent progress on the implementation of a hardware free-space optical communications test-bed. The test-bed implements an end-to-end communications system comprising a data encoder, modulator, laser-transmitter, telescope, detector, receiver and error-correction-code decoder. Implementation of each of the component systems is discussed, with an emphasis on 'real-world' system performance degradation and limitations. We have demonstrated real-time data rates of 44 Mbps and photon efficiencies of approximately 1.8 bits/photon over a 100m free-space optical link.

Space Communication and Navigation Testbed Communications Technology for Exploration

NASA Technical Reports Server (NTRS)

Reinhart, Richard

2013-01-01

NASA developed and launched an experimental flight payload (referred to as the Space Communication and Navigation Test Bed) to investigate software defined radio, networking, and navigation technologies, operationally in the space environment. The payload consists of three software defined radios each compliant to NASAs Space Telecommunications Radio System Architecture, a common software interface description standard for software defined radios. The software defined radios are new technology developed by NASA and industry partners. The payload is externally mounted to the International Space Station truss and available to NASA, industry, and university partners to conduct experiments representative of future mission capability. Experiment operations include in-flight reconfiguration of the SDR waveform functions and payload networking software. The flight system communicates with NASAs orbiting satellite relay network, the Tracking, Data Relay Satellite System at both S-band and Ka-band and to any Earth-based compatible S-band ground station.

Design of compact off-axis four-mirror anastigmatic system for space communications

NASA Astrophysics Data System (ADS)

Zhao, Fa-cai; Sun, Quan-she; Chen, Kun-feng; Zhu, Xing-bang; Wang, Shao-shui; Wang, Guo-quan; Zheng, Xiang-liang

2013-08-01

The deployment of advanced hyperspectral imaging and other Earth sensing instruments onboard Earth observing satellites is driving the demand for high-data rate communications. Space laser communications technology offers the potential for significantly increasing in data return capability from space to Earth. Compared to the current state of the art radio frequency communications links, lasercom links operate at much higher carrier frequencies. The use of higher carrier frequencies implies a much smaller diffraction loss, which in turn, results in a much higher efficiency in delivering the signal energy. Optical communications meet the required data rates with small, low-mass, and low-power communications packages. The communications optical system assembly typically consists of a front aperture, reflection or refraction type telescope, with or without a solar rejection filter, aft optics, fine-pointing mirrors, and array detectors. Optical system used in space laser communications usually has long focal length, large aperture compared with common optical systems. So the reflective optical system is widely used. An unobstructed four-mirror anastigmatic telescope system was proposed, which was modified based on the theory about geometry optics of common-axis three-mirror systems. Intermediate image was between secondary and tertiary mirror. In order to fold the optical path, four-mirror was designed by adding the plane reflective mirror at intermediate image. The design was analyzed, then a system with effective aperture of 200mm and field of view of 1.0°x1.0° was designed, total length and magnification are 700mm and 20, respectively. The system has advantages of large magnification, relative short physical size and loose manufacturing tolerances.

The computer-communication link for the innovative use of Space Station

NASA Technical Reports Server (NTRS)

Carroll, C. C.

1984-01-01

The potential capability of the computer-communications system link of space station is related to innovative utilization for industrial applications. Conceptual computer network architectures are presented and their respective accommodation of innovative industrial projects are discussed. To achieve maximum system availability for industrialization is a possible design goal, which would place the industrial community in an interactive mode with facilities in space. A worthy design goal would be to minimize the computer-communication management function and thereby optimize the system availability for industrial users. Quasi-autonomous modes and subnetworks are key design issues, since they would be the system elements directly effecting the system performance for industrial use.

Space Communications

DTIC Science & Technology

1977-03-15

Current capabilities of solid-state power devices (IMPATTs, bipolar, and field- effect tran- sistors) have been reviewed with regard to use in space ...Quarterly Technical Summary CO CD > -n_ or CJ> Space Communications Prepared for the Department of the Air Force under Electronic Systems...document when it is no longer needed. mm .■ ■■■ ■ ■ MASSACHUSETTS INSTITUTE OF TECHNOLOGY LINCOLN LABORATORY SPACE COMMUNICATIONS

Space Communication and Navigation SDR Testbed, Overview and Opportunity for Experiments

NASA Technical Reports Server (NTRS)

Reinhart, Richard C.

2013-01-01

NASA has developed an experimental flight payload (referred to as the Space Communication and Navigation (SCAN) Test Bed) to investigate software defined radio (SDR) communications, networking, and navigation technologies, operationally in the space environment. The payload consists of three software defined radios each compliant to NASAs Space Telecommunications Radio System Architecture, a common software interface description standard for software defined radios. The software defined radios are new technology developments underway by NASA and industry partners launched in 2012. The payload is externally mounted to the International Space Station truss to conduct experiments representative of future mission capability. Experiment operations include in-flight reconfiguration of the SDR waveform functions and payload networking software. The flight system will communicate with NASAs orbiting satellite relay network, the Tracking and Data Relay Satellite System at both S-band and Ka-band and to any Earth-based compatible S-band ground station. The system is available for experiments by industry, academia, and other government agencies to participate in the SDR technology assessments and standards advancements.

Free-space laser communication system with rapid acquisition based on astronomical telescopes.

PubMed

Wang, Jianmin; Lv, Junyi; Zhao, Guang; Wang, Gang

2015-08-10

The general structure of a free-space optical (FSO) communication system based on astronomical telescopes is proposed. The light path for astronomical observation and for communication can be easily switched. A separate camera is used as a star sensor to determine the pointing direction of the optical terminal's antenna. The new system exhibits rapid acquisition and is widely applicable in various astronomical telescope systems and wavelengths. We present a detailed analysis of the acquisition time, which can be decreased by one order of magnitude compared with traditional optical communication systems. Furthermore, we verify software algorithms and tracking accuracy.

Modeling and Analysis of Space Based Transceivers

NASA Technical Reports Server (NTRS)

Moore, Michael S.; Price, Jeremy C.; Reinhart, Richard; Liebetreu, John; Kacpura, Tom J.

2005-01-01

This paper presents the tool chain, methodology, and results of an on-going study being performed jointly by Space Communication Experts at NASA Glenn Research Center (GRC), General Dynamics C4 Systems (GD), and Southwest Research Institute (SwRI). The team is evaluating the applicability and tradeoffs concerning the use of Software Defined Radio (SDR) technologies for Space missions. The Space Telecommunications Radio Systems (STRS) project is developing an approach toward building SDR-based transceivers for space communications applications based on an accompanying software architecture that can be used to implement transceivers for NASA space missions. The study is assessing the overall cost and benefit of employing SDR technologies in general, and of developing a software architecture standard for its space SDR transceivers. The study is considering the cost and benefit of existing architectures, such as the Joint Tactical Radio Systems (JTRS) Software Communications Architecture (SCA), as well as potential new space-specific architectures.

Vinogradov uses a communication system in the SM during Expedition 13

NASA Image and Video Library

2006-06-22

ISS013-E-40015 (22 June 2006) --- Cosmonaut Pavel V. Vinogradov, Expedition 13 commander representing Russia's Federal Space Agency, uses a communication system in the Zvezda Service Module of the International Space Station.

A review on channel models in free space optical communication systems

NASA Astrophysics Data System (ADS)

Anbarasi, K.; Hemanth, C.; Sangeetha, R. G.

2017-12-01

Free Space Optical communication (FSO) is a wireless communication technology which uses light to transmit the data in free space. FSO has advantages like unlicensed spectrum and higher bandwidth. In this paper FSO system merits and demerits, challenges in FSO, and various channel models are discussed. To mitigate the turbulence in FSO the mitigation techniques like relaying, diversity schemes and adopting different modulation techniques used in different channels are discussed and its performance comparison is given.

7.3 Communications and Navigation

NASA Technical Reports Server (NTRS)

Manning, Rob

2005-01-01

This presentation gives an overview of the networks NASA currently uses to support space communications and navigation, and the requirements for supporting future deep space missions, including manned lunar and Mars missions. The presentation addresses the Space Network, Deep Space Network, and Ground Network, why new support systems are needed, and the potential for catastrophic failure of aging antennas. Space communications and navigation are considered during Aerocapture, Entry, Descent and Landing (AEDL) only in order to precisely position, track and interact with the spacecraft at its destination (moon, Mars and Earth return) arrival. The presentation recommends a combined optical/radio frequency strategy for deep space communications.

Space Station needs, attributes and architectural options. Volume 2, book 2, part 3: Communication system

NASA Technical Reports Server (NTRS)

1983-01-01

Preliminary results of the study of the architecture and attributes of the RF communications and tracking subsystem of the space station are summarized. Only communications between the space station and other external elements such as TDRSS satellites, low-orbit spacecraft, OTV, MOTV, in the general environment of the space station are considered. The RF communications subsystem attributes and characteristics are defined and analyzed key issues are identified for evolution from an initial space station (1990) to a year 2000 space station. The mass and power characteristics of the communications subsystem for the initial space station are assessed as well as the impact of advanced technology developments. Changes needed to the second generation TDRSS to accommodate the evolutionary space station of the year 2000 are also identified.

Advanced Communications Architecture Demonstration Made Significant Progress

NASA Technical Reports Server (NTRS)

Carek, David Andrew

2004-01-01

Simulation for a ground station located at 44.5 deg latitude. The Advanced Communications Architecture Demonstration (ACAD) is a concept architecture to provide high-rate Ka-band (27-GHz) direct-to-ground delivery of payload data from the International Space Station. This new concept in delivering data from the space station targets scientific experiments that buffer data onboard. The concept design provides a method to augment the current downlink capability through the Tracking Data Relay Satellite System (TDRSS) Ku-band (15-GHz) communications system. The ACAD concept pushes the limits of technology in high-rate data communications for space-qualified systems. Research activities are ongoing in examining the various aspects of high-rate communications systems including: (1) link budget parametric analyses, (2) antenna configuration trade studies, (3) orbital simulations (see the preceding figure), (4) optimization of ground station contact time (see the following graph), (5) processor and storage architecture definition, and (6) protocol evaluations and dependencies.

Embodied collaboration support system for 3D shape evaluation in virtual space

NASA Astrophysics Data System (ADS)

Okubo, Masashi; Watanabe, Tomio

2005-12-01

Collaboration mainly consists of two tasks; one is each partner's task that is performed by the individual, the other is communication with each other. Both of them are very important objectives for all the collaboration support system. In this paper, a collaboration support system for 3D shape evaluation in virtual space is proposed on the basis of both studies in 3D shape evaluation and communication support in virtual space. The proposed system provides the two viewpoints for each task. One is the viewpoint of back side of user's own avatar for the smooth communication. The other is that of avatar's eye for 3D shape evaluation. Switching the viewpoints satisfies the task conditions for 3D shape evaluation and communication. The system basically consists of PC, HMD and magnetic sensors, and users can share the embodied interaction by observing interaction between their avatars in virtual space. However, the HMD and magnetic sensors, which are put on the users, would restrict the nonverbal communication. Then, we have tried to compensate the loss of nodding of partner's avatar by introducing the speech-driven embodied interactive actor InterActor. Sensory evaluation by paired comparison of 3D shapes in the collaborative situation in virtual space and in real space and the questionnaire are performed. The result demonstrates the effectiveness of InterActor's nodding in the collaborative situation.

Orbiter Interface Unit and Early Communication System

NASA Technical Reports Server (NTRS)

Cobbs, Ronald M.; Cooke, Michael P.; Cox, Gary L.; Ellenberger, Richard; Fink, Patrick W.; Haynes, Dena S.; Hyams, Buddy; Ling, Robert Y.; Neighbors, Helen M.; Phan, Chau T.;

Channel coding in the space station data system network

NASA Technical Reports Server (NTRS)

Healy, T.

1982-01-01

A detailed discussion of the use of channel coding for error correction, privacy/secrecy, channel separation, and synchronization is presented. Channel coding, in one form or another, is an established and common element in data systems. No analysis and design of a major new system would fail to consider ways in which channel coding could make the system more effective. The presence of channel coding on TDRS, Shuttle, the Advanced Communication Technology Satellite Program system, the JSC-proposed Space Operations Center, and the proposed 30/20 GHz Satellite Communication System strongly support the requirement for the utilization of coding for the communications channel. The designers of the space station data system have to consider the use of channel coding.

Archambault uses communication equipment in the U.S. Laboratory during Joint Operations

NASA Image and Video Library

2007-06-12

S117-E-07097 (12 June 2007) --- Astronaut Lee Archambault, STS-117 pilot, uses a communication system near the controls of the Space Station Remote Manipulator System (SSRMS) or Canadarm2 in the Destiny laboratory of the International Space Station during flight day five activities while Space Shuttle Atlantis was docked with the station.

Adaptive Coding and Modulation Experiment With NASA's Space Communication and Navigation Testbed

NASA Technical Reports Server (NTRS)

Downey, Joseph; Mortensen, Dale; Evans, Michael; Briones, Janette; Tollis, Nicholas

2016-01-01

National Aeronautics and Space Administration (NASA)'s Space Communication and Navigation Testbed is an advanced integrated communication payload on the International Space Station. This paper presents results from an adaptive coding and modulation (ACM) experiment over S-band using a direct-to-earth link between the SCaN Testbed and the Glenn Research Center. The testing leverages the established Digital Video Broadcasting Second Generation (DVB-S2) standard to provide various modulation and coding options, and uses the Space Data Link Protocol (Consultative Committee for Space Data Systems (CCSDS) standard) for the uplink and downlink data framing. The experiment was conducted in a challenging environment due to the multipath and shadowing caused by the International Space Station structure. Several approaches for improving the ACM system are presented, including predictive and learning techniques to accommodate signal fades. Performance of the system is evaluated as a function of end-to-end system latency (round-trip delay), and compared to the capacity of the link. Finally, improvements over standard NASA waveforms are presented.

Adaptive Coding and Modulation Experiment With NASA's Space Communication and Navigation Testbed

NASA Technical Reports Server (NTRS)

Downey, Joseph A.; Mortensen, Dale J.; Evans, Michael A.; Briones, Janette C.; Tollis, Nicholas

2016-01-01

National Aeronautics and Space Administration (NASA)'s Space Communication and Navigation Testbed is an advanced integrated communication payload on the International Space Station. This paper presents results from an adaptive coding and modulation (ACM) experiment over S-band using a direct-to-earth link between the SCaN Testbed and the Glenn Research Center. The testing leverages the established Digital Video Broadcasting Second Generation (DVB-S2) standard to provide various modulation and coding options, and uses the Space Data Link Protocol (Consultative Committee for Space Data Systems (CCSDS) standard) for the uplink and downlink data framing. The experiment was con- ducted in a challenging environment due to the multipath and shadowing caused by the International Space Station structure. Several approaches for improving the ACM system are presented, including predictive and learning techniques to accommodate signal fades. Performance of the system is evaluated as a function of end-to-end system latency (round- trip delay), and compared to the capacity of the link. Finally, improvements over standard NASA waveforms are presented.

Effect of the incidence angle to free space optical communication based on cat-eye modulating retro-reflector

NASA Astrophysics Data System (ADS)

Zhang, Lai-xian; Sun, Hua-yan; Zhao, Yan-zhong; Zheng, Yong-hui; Shan, Cong-miao

2013-08-01

Based on the cat-eye effect of optical system, free space optical communication based on cat-eye modulating retro-reflector can build communication link rapidly. Compared to classical free space optical communication system, system based on cat-eye modulating retro-reflector has great advantages such as building communication link more rapidly, a passive terminal is smaller, lighter and lower power consuming. The incident angle is an important factor of cat-eye effect, so it will affect the retro-reflecting communication link. In this paper, the principle and work flow of free space optical communication based on cat-eye modulating retro-reflector were introduced. Then, using the theory of geometric optics, the equivalent model of modulating retro-reflector with incidence angle was presented. The analytical solution of active area and retro-reflected light intensity of cat-eye modulating retro-reflector were given. Noise of PIN photodetector was analyzed, based on which, bit error rate of free space optical communication based on cat-eye modulating retro-reflector was presented. Finally, simulations were done to study the effect of incidence angle to the communication. The simulation results show that the incidence angle has little effect on active area and retro-reflected light intensity when the incidence beam is in the active field angle of cat-eye modulating retro-reflector. With certain system and condition, the communication link can rapidly be built when the incidence light beam is in the field angle, and the bit error rate increases greatly with link range. When link range is smaller than 35Km, the bit error rate is less than 10-16.

Totally Connected Healthcare with TV White Spaces.

PubMed

Katzis, Konstantinos; Jones, Richard W; Despotou, Georgios

2017-01-01

Recent technological advances in electronics, wireless communications and low cost medical sensors generated a plethora of Wearable Medical Devices (WMDs), which are capable of generating considerably large amounts of new, unstructured real-time data. This contribution outlines how this data can be propagated to a healthcare system through the internet, using long distance Radio Access Networks (RANs) and proposes a novel communication system architecture employing White Space Devices (WSD) to provide seamless connectivity to its users. Initial findings indicate that the proposed communication system can facilitate broadband services over a large geographical area taking advantage of the freely available TV White Spaces (TVWS).

In-Space Internet-Based Communications for Space Science Platforms Using Commercial Satellite Networks

NASA Technical Reports Server (NTRS)

Kerczewski, Robert J.; Bhasin, Kul B.; Fabian, Theodore P.; Griner, James H.; Kachmar, Brian A.; Richard, Alan M.

1999-01-01

The continuing technological advances in satellite communications and global networking have resulted in commercial systems that now can potentially provide capabilities for communications with space-based science platforms. This reduces the need for expensive government owned communications infrastructures to support space science missions while simultaneously making available better service to the end users. An interactive, high data rate Internet type connection through commercial space communications networks would enable authorized researchers anywhere to control space-based experiments in near real time and obtain experimental results immediately. A space based communications network architecture consisting of satellite constellations connecting orbiting space science platforms to ground users can be developed to provide this service. The unresolved technical issues presented by this scenario are the subject of research at NASA's Glenn Research Center in Cleveland, Ohio. Assessment of network architectures, identification of required new or improved technologies, and investigation of data communications protocols are being performed through testbed and satellite experiments and laboratory simulations.

Enabling Future Science and Human Exploration with NASA's Next Generation Near Earth and Deep Space Communications and Navigation Architecture

NASA Technical Reports Server (NTRS)

Reinhart, Richard; Schier, James; Israel, David; Tai, Wallace; Liebrecht, Philip; Townes, Stephen

2017-01-01

The National Aeronautics and Space Administration (NASA) is studying alternatives for the United States space communications architecture through the 2040 timeframe. This architecture provides communication and navigation services to both human exploration and science missions throughout the solar system. Several of NASA's key space assets are approaching their end of design life and major systems are in need of replacement. The changes envisioned in the relay satellite architecture and capabilities around both Earth and Mars are significant undertakings and occur only once or twice each generation, and therefore is referred to as NASA's next generation space communications architecture. NASA's next generation architecture will benefit from technology and services developed over recent years. These innovations will provide missions with new operations concepts, increased performance, and new business and operating models. Advancements in optical communications will enable high-speed data channels and the use of new and more complex science instruments. Modern multiple beam/multiple access technologies such as those employed on commercial high throughput satellites will enable enhanced capabilities for on-demand service, and with new protocols will help provide Internet-like connectivity for cooperative spacecraft to improve data return and coordinate joint mission objectives. On-board processing with autonomous and cognitive networking will play larger roles to help manage system complexity. Spacecraft and ground systems will coordinate among themselves to establish communications, negotiate link connectivity, and learn to share spectrum to optimize resource allocation. Spacecraft will autonomously navigate, plan trajectories, and handle off-nominal events. NASA intends to leverage the ever-expanding capabilities of the satellite communications industry and foster its continued growth. NASA's technology development will complement and extend commercial capabilities to meet unique space environment requirements and to provide capabilities that are beyond the commercial marketplace. The progress of the communications industry, including the emerging global space internet segment and its planned constellations of 100's of satellites offer additional opportunities for new capability and mission concepts. The opportunities and challenges of a future space architecture require an optimal solution encompassing a global perspective. The concepts and technologies intentionally define an architecture that applies not only to NASA, but to other U.S. government agencies, international space and government agencies, and domestic and international industries to advance the openness, interoperability, and affordability of space communications. Cooperation among the worlds space agencies, their capabilities, standards, operations, and interoperability are key to advancing humankinds understand of the universe and extending human presence into the solar system.

Enabling Future Science and Human Exploration with NASA's Next Generation near Earth and Deep Space Communications and Navigation Architecture

NASA Technical Reports Server (NTRS)

Reinhart, Richard C.; Schier, James S.; Israel, David J.; Tai, Wallace; Liebrecht, Philip E.; Townes, Stephen A.

2017-01-01

The National Aeronautics and Space Administration (NASA) is studying alternatives for the United States space communications architecture through the 2040 timeframe. This architecture provides communication and navigation services to both human exploration and science missions throughout the solar system. Several of NASA's key space assets are approaching their end of design life and major systems are in need of replacement. The changes envisioned in the relay satellite architecture and capabilities around both Earth and Mars are significant undertakings and occur only once or twice each generation, and therefore is referred to as NASA's next generation space communications architecture. NASA's next generation architecture will benefit from technology and services developed over recent years. These innovations will provide missions with new operations concepts, increased performance, and new business and operating models. Advancements in optical communications will enable high-speed data channels and the use of new and more complex science instruments. Modern multiple beam/multiple access technologies such as those employed on commercial high throughput satellites will enable enhanced capabilities for on-demand service, and with new protocols will help provide Internet-like connectivity for cooperative spacecraft to improve data return and coordinate joint mission objectives. On-board processing with autonomous and cognitive networking will play larger roles to help manage system complexity. Spacecraft and ground systems will coordinate among themselves to establish communications, negotiate link connectivity, and learn to share spectrum to optimize resource allocation. Spacecraft will autonomously navigate, plan trajectories, and handle off-nominal events. NASA intends to leverage the ever-expanding capabilities of the satellite communications industry and foster its continued growth. NASA's technology development will complement and extend commercial capabilities to meet unique space environment requirements and to provide capabilities that are beyond the commercial marketplace. The progress of the communications industry, including the emerging global space internet segment and its planned constellations of 100's of satellites offer additional opportunities for new capability and mission concepts. The opportunities and challenges of a future space architecture require an optimal solution encompassing a global perspective. The concepts and technologies intentionally define an architecture that applies not only to NASA, but to other U.S. government agencies, international space and government agencies, and domestic and international industries to advance the openness, interoperability, and affordability of space communications. Cooperation among the worlds space agencies, their capabilities, standards, operations, and interoperability are key to advancing humankind's understand of the universe and extending human presence into the solar system.

Systems analysis of the space shuttle. [communication systems, computer systems, and power distribution

NASA Technical Reports Server (NTRS)

Schilling, D. L.; Oh, S. J.; Thau, F.

1975-01-01

Developments in communications systems, computer systems, and power distribution systems for the space shuttle are described. The use of high speed delta modulation for bit rate compression in the transmission of television signals is discussed. Simultaneous Multiprocessor Organization, an approach to computer organization, is presented. Methods of computer simulation and automatic malfunction detection for the shuttle power distribution system are also described.

CCSDS Overview

NASA Technical Reports Server (NTRS)

Kearney, Mike

2013-01-01

The primary goal of Consultative Committee for Space Data Systems (CCSDS) is interoperability between communications and data systems of space agencies' vehicles, facilities, missions and programs. Of all of the technologies used in spaceflight, standardization of communications and data systems brings the most benefit to multi-agency interoperability. CCSDS Started in 1982 developing standards at the lower layers of the protocol stack. The CCSDS scope has grown to cover standards throughout the entire ISO communications stack, plus other Data Systems areas (architecture, archive, security, XML exchange formats, etc.

Task one report: Optical system study. [characteristics of laser equipment for space communication systems

NASA Technical Reports Server (NTRS)

1973-01-01

An optical system which can be incorporated in a present day or near future space-borne laser communications system is described. Techniques of implementing these systems are presented and their design problems and use are discussed. Optical system weight is estimated as a function of aperture diameter for a typical present day or near future laser communication system. The optical communications system considered is a two-way, high data rate optical communications link from a spacecraft to a spacecraft or from a spacecraft to a ground station. Each station has a laser transmitter and receiver and a pointing and tracking system. Thus each station can track the laser transmitter of the other. Optical beamwidths are considered to be as small as an arc-second with the beam pointed to a fraction of this beamwidth.

Optical Communications in Support of Science from the Moon, Mars, and Beyond

NASA Technical Reports Server (NTRS)

Edwards, Bernard L.

2005-01-01

Optical communications can provide high speed communications throughout the solar system. Enable new science missions and human exploration. The technology suitable for near-earth optical communications, including communications to and from the Moon, is different than for deep space optical. NASA could leverage DoD investments for near-earth applications, including the moon. NASA will have to develop its own technology for deep space. The Mars laser communication demonstration is a pathfinder. NASA,s science mission directorate, under the leadership of Dr. Barry Geldzahler, is developing a roadmap for the development of deep space optical communications.

Technology Development for High Efficiency Optical Communications

NASA Technical Reports Server (NTRS)

Farr, William H.

2012-01-01

Deep space optical communications is a significantly more challenging operational domain than near Earth space optical communications, primarily due to effects resulting from the vastly increased range between transmitter and receiver. The NASA Game Changing Development Program Deep Space Optical Communications Project is developing four key technologies for the implementation of a high efficiency telecommunications system that will enable greater than 10X the data rate of a state-of-the-art deep space RF system (Ka-band) for similar transceiver mass and power burden on the spacecraft. These technologies are a low mass spacecraft disturbance isolation assembly, a flight qualified photon counting detector array, a high efficiency flight laser amplifier and a high efficiency photon counting detector array for the ground-based receiver.

Overlapping and permeability: Research on the pattern hierarchy of communication space and design strategy based on environmental behavior

NASA Astrophysics Data System (ADS)

Leilei, Sun; Liang, Zhang; Bing, Chen; Hong, Xi

2017-11-01

This thesis is to analyze the basic pattern hierarchy of communication space by using the theory of environmental psychology and behavior combined with relevant principles in architecture, to evaluate the design and improvement of communication space in specific meaning, and to bring new observation ideas and innovation in design methods to the system of space, environment and behavior.

Software-Defined Radio for Space-to-Space Communications

NASA Technical Reports Server (NTRS)

Fisher, Ken; Jih, Cindy; Moore, Michael S.; Price, Jeremy C.; Abbott, Ben A.; Fritz, Justin A.

2011-01-01

A paper describes the Space- to-Space Communications System (SSCS) Software- Defined Radio (SDR) research project to determine the most appropriate method for creating flexible and reconfigurable radios to implement wireless communications channels for space vehicles so that fewer radios are required, and commonality in hardware and software architecture can be leveraged for future missions. The ability to reconfigure the SDR through software enables one radio platform to be reconfigured to interoperate with many different waveforms. This means a reduction in the number of physical radio platforms necessary to support a space mission s communication requirements, thus decreasing the total size, weight, and power needed for a mission.

X-Band CubeSat Communication System Demonstration

NASA Technical Reports Server (NTRS)

Altunc, Serhat; Kegege, Obadiah; Bundick, Steve; Shaw, Harry; Schaire, Scott; Bussey, George; Crum, Gary; Burke, Jacob C.; Palo, Scott; O'Conor, Darren

2015-01-01

Today's CubeSats mostly operate their communications at UHF- and S-band frequencies. UHF band is presently crowded, thus downlink communications are at lower data rates due to bandwidth limitations and are unreliable due to interference. This research presents an end-to-end robust, innovative, compact, efficient and low cost S-band uplink and X-band downlink CubeSat communication system demonstration between a balloon and a Near Earth Network (NEN) ground system. Since communication systems serve as umbilical cords for space missions, demonstration of this X-band communication system is critical for successfully supporting current and future CubeSat communication needs. This research has three main objectives. The first objective is to design, simulate, and test a CubeSat S- and X-band communication system. Satellite Tool Kit (STK) dynamic link budget calculations and HFSS Simulations and modeling results have been used to trade the merit of various designs for small satellite applications. S- and X-band antennas have been tested in the compact antenna test range at Goddard Space Flight Center (GSFC) to gather radiation pattern data. The second objective is simulate and test a CubeSat compatible X-band communication system at 12.5Mbps including S-band antennas, X-band antennas, Laboratory for Atmospheric and Space Physics (LASP) /GSFC transmitter and an S-band receiver from TRL-5 to TRL-8 by the end of this effort. Different X-band communication system components (antennas, diplexers, etc.) from GSFC, other NASA centers, universities, and private companies have been investigated and traded, and a complete component list for the communication system baseline has been developed by performing analytical and numerical analysis. This objective also includes running simulations and performing trades between different X-band antenna systems to optimize communication system performance. The final objective is to perform an end-to-end X-band CubeSat communication system demonstration between a balloon and/or a sounding rocket and a Near Earth Network (NEN) ground system. This paper presents CubeSat communication systems simulation results, analysis of X-band and S-band antennas and RF front-end components, transceiver design, analysis and optimization of space-to-ground communication performance, subsystem development, as well as the test results for an end-to-end X-band CubeSat communication system demonstration. The outcome of this work will be used to pave the way for next generation NEN-compatible X-band CubeSat communication systems to support higher data rates with more advanced modulation and forward error correction (FEC) coding schemes, and to support and attract new science missions at lower cost. It also includes an abbreviated concept of operations for CubeSat users to utilize the NEN, starting from first contact with NASA's communication network and continuing through on-orbit operations.

Variable Coding and Modulation Experiment Using NASA's Space Communication and Navigation Testbed

NASA Technical Reports Server (NTRS)

Downey, Joseph A.; Mortensen, Dale J.; Evans, Michael A.; Tollis, Nicholas S.

2016-01-01

National Aeronautics and Space Administration (NASA)'s Space Communication and Navigation Testbed on the International Space Station provides a unique opportunity to evaluate advanced communication techniques in an operational system. The experimental nature of the Testbed allows for rapid demonstrations while using flight hardware in a deployed system within NASA's networks. One example is variable coding and modulation, which is a method to increase data-throughput in a communication link. This paper describes recent flight testing with variable coding and modulation over S-band using a direct-to-earth link between the SCaN Testbed and the Glenn Research Center. The testing leverages the established Digital Video Broadcasting Second Generation (DVB-S2) standard to provide various modulation and coding options. The experiment was conducted in a challenging environment due to the multipath and shadowing caused by the International Space Station structure. Performance of the variable coding and modulation system is evaluated and compared to the capacity of the link, as well as standard NASA waveforms.

Deep space communication - A one billion mile noisy channel

NASA Technical Reports Server (NTRS)

Smith, J. G.

1982-01-01

Deep space exploration is concerned with the study of natural phenomena in the solar system with the aid of measurements made at spacecraft on deep space missions. Deep space communication refers to communication between earth and spacecraft in deep space. The Deep Space Network is an earth-based facility employed for deep space communication. It includes a network of large tracking antennas located at various positions around the earth. The goals and achievements of deep space exploration over the past 20 years are discussed along with the broad functional requirements of deep space missions. Attention is given to the differences in space loss between communication satellites and deep space vehicles, effects of the long round-trip light time on spacecraft autonomy, requirements for the use of massive nuclear power plants on spacecraft at large distances from the sun, and the kinds of scientific return provided by a deep space mission. Problems concerning a deep space link of one billion miles are also explored.

Cooperating Expert Systems For Space Station Power Distribution Management

NASA Astrophysics Data System (ADS)

Nguyen, T. A.; Chiou, W. C.

1987-02-01

In a complex system such as the manned Space Station, it is deem necessary that many expert systems must perform tasks in a concurrent and cooperative manner. An important question arise is: what cooperative-task-performing models are appropriate for multiple expert systems to jointly perform tasks. The solution to this question will provide a crucial automation design criteria for the Space Station complex systems architecture. Based on a client/server model for performing tasks, we have developed a system that acts as a front-end to support loosely-coupled communications between expert systems running on multiple Symbolics machines. As an example, we use two ART*-based expert systems to demonstrate the concept of parallel symbolic manipulation for power distribution management and dynamic load planner/scheduler in the simulated Space Station environment. This on-going work will also explore other cooperative-task-performing models as alternatives which can evaluate inter and intra expert system communication mechanisms. It will be served as a testbed and a bench-marking tool for other Space Station expert subsystem communication and information exchange.

Overview of NASA Glenn Research Center's Communications and Intelligent Systems Division

NASA Technical Reports Server (NTRS)

Miranda, Felix A.

2016-01-01

The Communications and Intelligent Systems Division provides expertise, plans, conducts and directs research and engineering development in the competency fields of advanced communications and intelligent systems technologies for application in current and future aeronautics and space systems.

The Telecommunications and Data Acquisition Report

NASA Technical Reports Server (NTRS)

Posner, E. C. (Editor)

1991-01-01

This quarterly reports on space communications, radio navigation, radio science, and ground based radio and radar astronomy in connection with the Deep Space Network (DSN) in planning, supporting research and technology, implementation, and in operations. Also included is standards activity at JPL for space data and information systems and DSN work. Specific areas of research are: Tracking and ground based navigation; Spacecraft and ground communications; Station control and system technology; DSN Systems Implementation; and DSN Operations.

Space Shuttle program communication and tracking systems interface analysis

NASA Technical Reports Server (NTRS)

Dodds, J. G.; Holmes, J. K.; Huth, G. K.; Iwasaki, R. S.; Nilsen, P. W.; Polydoros, A.; Sampaio, D. R.; Udalov, S.

1984-01-01

The Space Shuttle Program Communications and Tracking Systems Interface Analysis began April 18, 1983. During this time, the shuttle communication and tracking systems began flight testing. Two areas of analysis documented were a result of observations made during flight tests. These analyses involved the Ku-band communication system. First, there was a detailed analysis of the interface between the solar max data format and the Ku-band communication system including the TDRSS ground station. The second analysis involving the Ku-band communication system was an analysis of the frequency lock loop of the Gunn oscillator used to generate the transmit frequency. The stability of the frequency lock loop was investigated and changes to the design were reviewed to alleviate the potential loss of data due the loop losing lock and entering the reacquisition mode. Other areas of investigation were the S-band antenna analysis and RF coverage analysis.

Block Oriented Simulation System (BOSS)

NASA Technical Reports Server (NTRS)

Ratcliffe, Jaimie

1988-01-01

Computer simulation is assuming greater importance as a flexible and expedient approach to modeling system and subsystem behavior. Simulation has played a key role in the growth of complex, multiple access space communications such as those used by the space shuttle and the TRW-built Tracking and Data Relay Satellites (TDRS). A powerful new simulator for use in designing and modeling the communication system of NASA's planned Space Station is being developed. Progress to date on the Block (Diagram) Oriented Simulation System (BOSS) is described.

An operations management system for the Space Station

NASA Astrophysics Data System (ADS)

Savage, Terry R.

A description is provided of an Operations Management System (OMS) for the planned NASA Space Station. The OMS would be distributed both in space and on the ground, and provide a transparent interface to the communications and data processing facilities of the Space Station Program. The allocation of OMS responsibilities has, in the most current Space Station design, been fragmented among the Communications and Tracking Subsystem (CTS), the Data Management System (DMS), and a redefined OMS. In this current view, OMS is less of a participant in the real-time processing, and more an overseer of the health and management of the Space Station operations.

Free-space quantum cryptography with quantum and telecom communication channels

NASA Astrophysics Data System (ADS)

Toyoshima, Morio; Takayama, Yoshihisa; Klaus, Werner; Kunimori, Hiroo; Fujiwara, Mikio; Sasaki, Masahide

2008-07-01

Quantum cryptography is a new technique that uses the laws of physics to transmit information securely. In such systems, the vehicle to transfer quantum information is a single photon. However, the transmission distance is limited by the absorption of photons in an optical fiber in which the maximum demonstrated range is about 100 km. Free-space quantum cryptography between a ground station and a satellite is a way of sending the quantum information further distances than that with optical fibers since there is no birefringence effect in the atmosphere. At the National Institute of Information and Communications Technology (NICT), the laser communication demonstration between the NICT optical ground station and a low earth orbit satellite was successfully conducted in 2006. For such space communication links, free-space quantum cryptography is considered to be an important application in the future. We have developed a prototype system for free-space quantum cryptography using a weak coherent light and a telecom communication channel. The preliminary results are presented.

A Plan for the Development and Demonstration of Optical Communications for Deep Space

NASA Technical Reports Server (NTRS)

Lesh, J. R.; Deutsch, L. J.; Weber, W. J.

1990-01-01

In this article, an overall plan for the development and demonstration of optical communications for deep-space applications is presented. The current state of the technology for optical communications is presented. Then, the development and demonstration plan is presented in two parts: the overall major systems activities, followed by the generic technology developments that will enable them. The plan covers the path from laboratory subsystems demonstrations out to a full-scale flight experiment system for the proposed Mars Communications Relay Orbiter mission.

Spacecraft VHF Radio Propagation Analysis in Ocean Environments Including Atmospheric Effects

NASA Technical Reports Server (NTRS)

Hwu, Shian; Moreno, Gerardo; Desilva, Kanishka; Jih, CIndy

2010-01-01

The Communication Systems Simulation Laboratory (CSSL) at the National Aeronautics and Space Administration (NASA)/Johnson Space Center (JSC) is tasked to perform spacecraft and ground network communication system simulations. The CSSL has developed simulation tools that model spacecraft communication systems and the space/ground environment in which they operate. This paper is to analyze a spacecraft's very high frequency (VHF) radio signal propagation and the impact to performance when landing in an ocean. Very little research work has been done for VHF radio systems in a maritime environment. Rigorous Radio Frequency (RF) modeling/simulation techniques were employed for various environmental effects. The simulation results illustrate the significance of the environmental effects on the VHF radio system performance.

Developing Architectures and Technologies for an Evolvable NASA Space Communication Infrastructure

NASA Technical Reports Server (NTRS)

Bhasin, Kul; Hayden, Jeffrey

2004-01-01

Space communications architecture concepts play a key role in the development and deployment of NASA's future exploration and science missions. Once a mission is deployed, the communication link to the user needs to provide maximum information delivery and flexibility to handle the expected large and complex data sets and to enable direct interaction with the spacecraft and experiments. In human and robotic missions, communication systems need to offer maximum reliability with robust two-way links for software uploads and virtual interactions. Identifying the capabilities to cost effectively meet the demanding space communication needs of 21st century missions, proper formulation of the requirements for these missions, and identifying the early technology developments that will be needed can only be resolved with architecture design. This paper will describe the development of evolvable space communication architecture models and the technologies needed to support Earth sensor web and collaborative observation formation missions; robotic scientific missions for detailed investigation of planets, moons, and small bodies in the solar system; human missions for exploration of the Moon, Mars, Ganymede, Callisto, and asteroids; human settlements in space, on the Moon, and on Mars; and great in-space observatories for observing other star systems and the universe. The resulting architectures will enable the reliable, multipoint, high data rate capabilities needed on demand to provide continuous, maximum coverage of areas of concentrated activities, such as in the vicinity of outposts in-space, on the Moon or on Mars.

Evolving the NASA Near Earth Network for the Next Generation of Human Space Flight

NASA Technical Reports Server (NTRS)

Roberts, Christopher J.; Carter, David L.; Hudiburg, John J.; Tye, Robert N.; Celeste, Peter B.

2014-01-01

The purpose of this paper is to present the planned development and evolution of the NASA Near Earth Network (NEN) launch communications services in support of the next generation of human space flight programs. Following the final space shuttle mission in 2011, the two NEN launch communications stations were decommissioned. Today, NASA is developing the next generation of human space flight systems focused on exploration missions beyond low-earth orbit, and supporting the emerging market for commercial crew and cargo human space flight services. The NEN is leading a major initiative to develop a modern high data rate launch communications ground architecture with support from the Kennedy Space Center Ground Systems Development and Operations Program and in partnership with the U.S. Air Force (USAF) Eastern Range. This initiative, the NEN Launch Communications Stations (LCS) development project, successfully completed its System Requirements Review in November 2013. This paper provides an overview of the LCS project and a summary of its progress. The LCS ground architecture, concept of operations, and driving requirements to support the new heavy-lift Space Launch System and Orion Multi-Purpose Crew Vehicle for Exploration Mission-1 are presented. Finally, potential future extensions to the ground architecture beyond EM-1 are discussed.

In-Space Networking on NASA's SCAN Testbed

NASA Technical Reports Server (NTRS)

Brooks, David E.; Eddy, Wesley M.; Clark, Gilbert J.; Johnson, Sandra K.

2016-01-01

The NASA Space Communications and Navigation (SCaN) Testbed, an external payload onboard the International Space Station, is equipped with three software defined radios and a flight computer for supporting in-space communication research. New technologies being studied using the SCaN Testbed include advanced networking, coding, and modulation protocols designed to support the transition of NASAs mission systems from primarily point to point data links and preplanned routes towards adaptive, autonomous internetworked operations needed to meet future mission objectives. Networking protocols implemented on the SCaN Testbed include the Advanced Orbiting Systems (AOS) link-layer protocol, Consultative Committee for Space Data Systems (CCSDS) Encapsulation Packets, Internet Protocol (IP), Space Link Extension (SLE), CCSDS File Delivery Protocol (CFDP), and Delay-Tolerant Networking (DTN) protocols including the Bundle Protocol (BP) and Licklider Transmission Protocol (LTP). The SCaN Testbed end-to-end system provides three S-band data links and one Ka-band data link to exchange space and ground data through NASAs Tracking Data Relay Satellite System or a direct-to-ground link to ground stations. The multiple data links and nodes provide several upgradable elements on both the space and ground systems. This paper will provide a general description of the testbeds system design and capabilities, discuss in detail the design and lessons learned in the implementation of the network protocols, and describe future plans for continuing research to meet the communication needs for evolving global space systems.

Communications and Intelligent Systems Division Overview

NASA Technical Reports Server (NTRS)

Emerson, Dawn

2017-01-01

This presentation provides an overview of the research and engineering work being performed in the competency fields of advanced communications and intelligent systems with emphasis on advanced technologies, architecture definition, and systems development for application in current and future aeronautics and space communications systems.

46 CFR 130.440 - Communications system.

Code of Federal Regulations, 2010 CFR

2010-10-01

... 46 Shipping 4 2010-10-01 2010-10-01 false Communications system. 130.440 Section 130.440 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) OFFSHORE SUPPLY VESSELS VESSEL CONTROL, AND MISCELLANEOUS EQUIPMENT AND SYSTEMS Automation of Unattended Machinery Spaces § 130.440 Communications system...

Communications and Intelligent Systems Division - Division Overview

NASA Technical Reports Server (NTRS)

Miranda, Felix A.

2017-01-01

This presentation provides an overview of the research and engineering work being performed in the competency fields of advanced communications and intelligent systems with emphasis on advanced technologies, architecture definition,and systems development for application in current and future aeronautics and space communications systems.

Communications and Intelligent Systems Division - Division Overview

NASA Technical Reports Server (NTRS)

Miranda, Felix A.

2017-01-01

This presentation provides an overview of the research and engineering work being performed in the competency fields of advanced communications and intelligent systems with emphasis on advanced technologies, architecture definition, and systems development for application in current and future aeronautics and space communications systems.

Space information systems in the Space Station era; Proceedings of the AIAA/NASA International Symposium on Space Information Systems, Washington, DC and Greenbelt, MD, June 22, 23, 1987

NASA Technical Reports Server (NTRS)

Gerard, Mireille (Editor); Edwards, Pamela W. (Editor)

1988-01-01

Technological and planning issues for data management, processing, and communication on Space Station Freedom are discussed in reviews and reports by U.S., European, and Japanese experts. The space-information-system strategies of NASA, ESA, and NASDA are discussed; customer needs are analyzed; and particular attention is given to communication and data systems, standards and protocols, integrated system architectures, software and automation, and plans and approaches being developed on the basis of experience from past programs. Also included are the reports from workshop sessions on design to meet customer needs, the accommodation of growth and new technologies, and system interoperability.

A Summary of - An Earth-to-Deep Space Communications System with Adaptive Tilt and Scintillation Correction Using Near-Earth Relay Mirrors

NASA Technical Reports Server (NTRS)

Armstrong, J. W.; Yeh, C.; Wilson, K. E.

1998-01-01

Optical telecommunication will be the next technology for wide-band Earth/space communication. Uncompensated propagation through the Earth's atmosphere (e.g., scintillation and wavefront tilt) fundamentally degrade communication to distant spcaecraft.

Aeronautics and Space Report of the President: Fiscal Year 1996 Activities

NASA Technical Reports Server (NTRS)

1996-01-01

Topics considered include: (1) Space launch activities: space shuttle missions; expendable launch vehicles. (2) Space science: astronomy and space physics; solar system exploration. (3) Space flight and technology: life and microgravity sciences; space shuttle technology; reuseable launch vehicles; international space station; energy; safety and mission assurance; commercial development and regulation of space; surveillance. (4) Space communications: communications satellites; space network; ground networks; mission control and data systems. (5) Aeronautical activities: technology developments; air traffic control and navigation; weather-related aeronautical activities; flight safety and security; aviation medicine and human factors. (6) Studies of the planet earth: terrestrial studies and applications: atmospheric studies: oceanographic studies; international aeronautical and space activities; and appendices.

Reconfigurable Antenna and Cognitive Radio for Space Applications

NASA Technical Reports Server (NTRS)

Hwu, Shian U.

2012-01-01

This presentation briefly discusses a research effort on mitigation techniques of radio frequency interference (RFI) on communication systems for possible space applications. This problem is of considerable interest in the context of providing reliable communications to the space vehicle which might suffer severe performance degradation due to RFI sources such as visiting spacecrafts and various ground radar systems. This study proposes a communication system with Reconfigurable Antenna (RA) and Cognitive Radio (CR) to mitigate the RFI impact. A cognitive radio is an intelligent radio that is able to learn from the environment and adapt to the variations in its surrounding by adjusting the transmit power, carrier frequency, modulation strategy or transmission data rate. Therefore, the main objective of a cognitive radio system is to ensure highly reliable communication whenever and wherever needed. To match the intelligent adaptability of the cognitive radio, a reconfigurable antenna system will be required to ensure the system performance. The technical challenges in design such a system will be discussed in this presentation.

Navigation Flight Test Results from the Low Power Transceiver Communications and Navigation Demonstration on Shuttle (CANDOS) Experiment

NASA Technical Reports Server (NTRS)

Haas, Lin; Massey, Christopher; Baraban, Dmitri

2003-01-01

This paper presents the Global Positioning System (GPS) navigation results from the Communications and Navigation Demonstration on Shuttle (CANDOS) experiment flown on STS-107. This experiment was the initial flight of a Low Power Transceiver (LPT) that featured high capacity space- space and space-ground communications and GPS- based navigation capabilities. The LPT also hosted the GPS Enhanced Orbit Determination Experiment (GEODE) orbit determination software. All CANDOS test data were recovered during the mission using LPT communications links via the Tracking and Data Relay Satellite System (TDRSS). An overview of the LPT s navigation software and the GPS experiment timeline is presented, along with comparisons of test results to the NASA Johnson Space Center (JSC) real-time ground navigation vectors and Best Estimate of Trajectory (BET).

Improving Communications Systems

NASA Technical Reports Server (NTRS)

1997-01-01

The Space Shuttle has many communications systems which are used throughout a typical mission. Given that the radio spectrum has become increasingly congested, the ability to hear extremely weak signals requires greater receiver sensitivity. Dryden Flight Research Center approached Angle Linear, a manufacturer of linear radio frequency products and peripherals for communications, to solve the problem. The solution was a receiving preamplifier specially crafted for NASA. Communications with the Space Shuttle are now more reliable,with Dryden being able to also support local missions without purchasing additional equipment. The work has carried over into the Mir Space Station communication support effort and is under evaluation by other NASA centers. The company's preamplifier line was greatly expanded to cover a broader range of frequencies, providing the same sensational improvement to other areas of communication including business, government, trucking, land mobile, cellular and broadcast.

Wireless Communications in Space

NASA Technical Reports Server (NTRS)

2004-01-01

In 1992, NASA and the U.S. Department of Defense jointly commissioned the research and development of a technology solution to address the challenges and requirements of communicating with their spacecraft. The project yielded an international consortium composed of representatives from the space science community, industry, and academia. This group of experts developed a broad suite of protocols specifically designed for space-based communications, known today as Space Communications Protocol Standards (SCPS). Having been internationally standardized by the Consultative Committee on Space Data Systems and the International Standards Organization, SCPS is distributed as open source technology by NASA s Jet Propulsion Laboratory (JPL). The protocols are used for every national space mission that takes place today.

Beam width and transmitter power adaptive to tracking system performance for free-space optical communication.

PubMed

Arnon, S; Rotman, S; Kopeika, N S

1997-08-20

The basic free-space optical communication system includes at least two satellites. To communicate between them, the transmitter satellite must track the beacon of the receiver satellite and point the information optical beam in its direction. Optical tracking and pointing systems for free space suffer during tracking from high-amplitude vibration because of background radiation from interstellar objects such as the Sun, Moon, Earth, and stars in the tracking field of view or the mechanical impact from satellite internal and external sources. The vibrations of beam pointing increase the bit error rate and jam communication between the two satellites. One way to overcome this problem is to increase the satellite receiver beacon power. However, this solution requires increased power consumption and weight, both of which are disadvantageous in satellite development. Considering these facts, we derive a mathematical model of a communication system that adapts optimally the transmitter beam width and the transmitted power to the tracking system performance. Based on this model, we investigate the performance of a communication system with discrete element optical phased array transmitter telescope gain. An example for a practical communication system between a Low Earth Orbit Satellite and a Geostationary Earth Orbit Satellite is presented. From the results of this research it can be seen that a four-element adaptive transmitter telescope is sufficient to compensate for vibration amplitude doubling. The benefits of the proposed model are less required transmitter power and improved communication system performance.

The Telecommunications and Data Acquisition Report

NASA Technical Reports Server (NTRS)

Posner, E. C. (Editor)

1984-01-01

Activities in space communication, radio navigation, radio science, and ground-based astronomy are reported. Advanced systems for the Deep Space Network and its Ground-Communications Facility are discussed including station control and system technology. Network sustaining as well as data and information systems are covered. Studies of geodynamics, investigations of the microwave spectrum, and the search for extraterrestrial intelligence are reported.

Software-Implemented Fault Tolerance in Communications Systems

NASA Technical Reports Server (NTRS)

Gantenbein, Rex E.

1994-01-01

Software-implemented fault tolerance (SIFT) is used in many computer-based command, control, and communications (C(3)) systems to provide the nearly continuous availability that they require. In the communications subsystem of Space Station Alpha, SIFT algorithms are used to detect and recover from failures in the data and command link between the Station and its ground support. The paper presents a review of these algorithms and discusses how such techniques can be applied to similar systems found in applications such as manufacturing control, military communications, and programmable devices such as pacemakers. With support from the Tracking and Communication Division of NASA's Johnson Space Center, researchers at the University of Wyoming are developing a testbed for evaluating the effectiveness of these algorithms prior to their deployment. This testbed will be capable of simulating a variety of C(3) system failures and recording the response of the Space Station SIFT algorithms to these failures. The design of this testbed and the applicability of the approach in other environments is described.

Global services systems - Space communication

NASA Technical Reports Server (NTRS)

Shepphird, F. H.; Wolbers, H. L.

1979-01-01

The requirements projected to the year 2000 for space-based global service systems, including both personal communications and innovative services, are developed based on historic trends and anticipated worldwide demographic and economic growth patterns. The growing demands appear to be best satisfied by developing larger, more sophisticated space systems in order to reduce the size, complexity, and expense of ground terminals. The availability of low-cost ground terminals will, in turn, further stimulate the generation of new services and new customers.

Whither Space Power? Forging a Strategy for the New Century

DTIC Science & Technology

2002-09-01

cyber dimension. The physical assets that comprise communications networks— Courtesy of NASA Advanced Communication Technology Satellite 90...location to the energy produc­ tion and use site. As long-distance energy transmission be- comes feasible, this physical transport will undoubtedly mi­ grate...to space-based transmission systems much as communications systems have done and are continuing to do. 96 WORDEN Once this happens, we will have

Design, Development and Pre-Flight Testing of the Communications, Navigation, and Networking Reconfigurable Testbed (Connect) to Investigate Software Defined Radio Architecture on the International Space Station

NASA Technical Reports Server (NTRS)

Over, Ann P.; Barrett, Michael J.; Reinhart, Richard C.; Free, James M.; Cikanek, Harry A., III

2011-01-01

The Communication Navigation and Networking Reconfigurable Testbed (CoNNeCT) is a NASA-sponsored mission, which will investigate the usage of Software Defined Radios (SDRs) as a multi-function communication system for space missions. A softwaredefined radio system is a communication system in which typical components of the system (e.g., modulators) are incorporated into software. The software-defined capability allows flexibility and experimentation in different modulation, coding and other parameters to understand their effects on performance. This flexibility builds inherent redundancy and flexibility into the system for improved operational efficiency, real-time changes to space missions and enhanced reliability/redundancy. The CoNNeCT Project is a collaboration between industrial radio providers and NASA. The industrial radio providers are providing the SDRs and NASA is designing, building and testing the entire flight system. The flight system will be integrated on the Express Logistics Carrier (ELC) on the International Space Station (ISS) after launch on the H-IIB Transfer Vehicle in 2012. This paper provides an overview of the technology research objectives, payload description, design challenges and pre-flight testing results.

The Tracking & Data Relay Satellite System. The New Space Network.

ERIC Educational Resources Information Center

Froehlich, Walter

This publication describes the giant-capacity space communications installation called the "Tracking and Data Relay Satellite System" (TDRSS). Chapters include: (1) "A New Communications Bridge to Orbit" (illustrating what it is and how it looks); (2) "TDRSS Goes to Work" (describing how it functions); (3) "The…

Cryogenically cooled low-noise amplifier for radio-astronomical observations and centimeter-wave deep-space communications systems

NASA Astrophysics Data System (ADS)

Vdovin, V. F.; Grachev, V. G.; Dryagin, S. Yu.; Eliseev, A. I.; Kamaletdinov, R. K.; Korotaev, D. V.; Lesnov, I. V.; Mansfeld, M. A.; Pevzner, E. L.; Perminov, V. G.; Pilipenko, A. M.; Sapozhnikov, B. D.; Saurin, V. P.

2016-01-01

We report a design solution for a highly reliable, low-noise and extremely efficient cryogenically cooled transmit/receive unit for a large antenna system meant for radio-astronomical observations and deep-space communications in the X band. We describe our design solution and the results of a series of laboratory and antenna tests carried out in order to investigate the properties of the cryogenically cooled low-noise amplifier developed. The transmit/receive unit designed for deep-space communications (Mars missions, radio observatories located at Lagrangian point L2, etc.) was used in practice for communication with live satellites including "Radioastron" observatory, which moves in a highly elliptical orbit.

Multiscale free-space optical interconnects for intrachip global communication: motivation, analysis, and experimental validation.

PubMed

McFadden, Michael J; Iqbal, Muzammil; Dillon, Thomas; Nair, Rohit; Gu, Tian; Prather, Dennis W; Haney, Michael W

2006-09-01

The use of optical interconnects for communication between points on a microchip is motivated by system-level interconnect modeling showing the saturation of metal wire capacity at the global layer. Free-space optical solutions are analyzed for intrachip communication at the global layer. A multiscale solution comprising microlenses, etched compound slope microprisms, and a curved mirror is shown to outperform a single-scale alternative. Microprisms are designed and fabricated and inserted into an optical setup apparatus to experimentally validate the concept. The multiscale free-space system is shown to have the potential to provide the bandwidth density and configuration flexibility required for global communication in future generations of microchips.

Optical Communications Study for the Next Generation Space Telescope

NASA Technical Reports Server (NTRS)

Ceniceros, Juan M.

2000-01-01

The Next Generation Space Telescope (NGST), part of NASA's Origins program, is a follow on to the Hubble Space Telescope expected to provide timely new science along with answering fundamental questions. NGST is a large diameter, infrared optimized telescope with imaging and spectrographic detectors which will be used to help study the origin of galaxies. Due to the large data NGST will collect, Goddard Space Flight Center has considered the use of optical communications for data downlink. The Optical Communications Group at the Jet Propulsion Laboratory has performed a study on optical communications systems for NGST. The objective of the study was to evaluate the benefits gained through the use of optical communication technologies. Studies were performed for each of four proposed NGST orbits. The orbits considered were an elliptical orbit about the semi stable second Lagrangian point, a 1 by 3 AU elliptic orbit around the sun, a 1 AU drift orbit, and a 1 AU drift orbit at a 15 degree incline to the ecliptic plane. An appropriate optical communications system was determined for each orbit. Systems were evaluated in terms of mass, power consumption, size, and cost for each of the four proposed orbits.

Space-to-Space Communications System

NASA Technical Reports Server (NTRS)

Tu, Kwei; Gaylor, Kent; Vitalpur, Sharada; Sham, Cathy

1999-01-01

The Space-to-Space Communications System (SSCS) is an Ultra High Frequency (UHF) Time-Division-Multiple Access (TDMA) system that is designed, developed, and deployed by the NASA Johnson Space Center (JSC) to provide voice, commands, telemetry and data services in close proximity among three space elements: International Space Station (ISS), Space Shuttle Orbiter, and Extravehicular Mobility Units (EMU). The SSCS consists of a family of three radios which are, Space-to-Space Station Radio (SSSR), Space-to-Space Orbiter Radio (SSOR), and Space-to-Space Extravehicular Mobility Radio (SSER). The SSCS can support up to five such radios at a time. Each user has its own time slot within which to transmit voice and data. Continuous Phase Frequency Shift Keying (CPFSK) carrier modulation with a burst data rate of 695 kbps and a frequency deviation of 486.5 kHz is employed by the system. Reed-Solomon (R-S) coding is also adopted to ensure data quality. In this paper, the SSCS system requirements, operational scenario, detailed system architecture and parameters, link acquisition strategy, and link performance analysis will be presented and discussed

Defense AT and L. Volume 43, Number 1

DTIC Science & Technology

2014-02-01

community on the strategic direction of future space system acquisitions. Should we continue and/or improve aggregated space systems over time or move...desirable. Schedulers must have a firm command of project manage- ment theory and practice and possess leadership and communication skills. Scorecard...idea was recommended by the Defense Sci- ence Board’s Munitions System Reliability report. In the future, such systems conceivably could communicate

Experimental results of 5-Gbps free-space coherent optical communications with adaptive optics

NASA Astrophysics Data System (ADS)

Chen, Mo; Liu, Chao; Rui, Daoman; Xian, Hao

2018-07-01

In a free-space optical communication system with fiber optical components, the received signal beam must be coupled into a single-mode fiber (SMF) before being amplified and detected. The impacts analysis of tracking errors and wavefront distortion on SMF coupling show that under the condition of relatively strong turbulence, only the tracking errors compensation is not enough, and turbulence wavefront aberration is required to be corrected. Based on our previous study and design of SMF coupling system with a 137-element continuous surface deformable mirror AO unit, we perform an experiment of a 5-Gbps Free-space Coherent Optical Communication (FSCOC) system, in which the eye pattern and Bit-error Rate (BER) are displayed. The comparative results are shown that the influence of the atmospheric is fatal in FSCOC systems. The BER of coherent communication is under 10-6 with AO compensation, which drops significantly compared with the BER without AO correction.

Shuttle communications design study

NASA Technical Reports Server (NTRS)

Cartier, D. E.

1975-01-01

The design and development of a space shuttle communication system are discussed. The subjects considered include the following: (1) Ku-band satellite relay to shuttle, (2) phased arrays, (3) PN acquisition, (4) quadriplexing of direct link ranging and telemetry, (5) communications blackout on launch and reentry, (6) acquisition after blackout on reentry, (7) wideband communications interface with the Ku-Band rendezvous radar, (8) aeroflight capabilities of the space shuttle, (9) a triple multiplexing scheme equivalent to interplex, and (10) a study of staggered quadriphase for use on the space shuttle.

Reflector control technology in space laser communication

NASA Astrophysics Data System (ADS)

Xie, Meilin; Ma, Caiwen; Yao, Cheng; Huang, Wei; Lian, Xuezheng; Feng, Xubin; Jing, Feng

2017-11-01

The optical frequencies band is used as information carrier to realize laser communication between two low-orbit micro-satellites in space which equipped with inter-satellite laser communication terminals, optical switches, space routers and other payload. The laser communication terminal adopts a two-dimensional turntable with a single mirror structure. In this paper, the perturbation model of satellite platform is established in this paper. The relationship between the coupling and coordinate transformation of satellite disturbance is analyzed and the laser pointing vector is deduced. Using the tracking differentiator to speed up the circular grating angle information constitute speed loop feedback, which avoids the problem of error amplification caused by the high frequency of the conventional difference algorithm. Finally, the suppression ability of the satellite platform disturbance and the tracking accuracy of the tracking system are simulated and analyzed. The results show that the tracking accuracy of the whole system is 10μrad in the case of satellite vibration, which provides the basis for the optimization of the performance of the space-borne laser communication control system.

Research-to-operations (R2O) for the Space Environmental Effects Fusion System (SEEFS) system-impact products

NASA Astrophysics Data System (ADS)

Quigley, Stephen

The Space Vehicles Directorate of the Air Force Research Laboratory (AFRL/RVBX) and the Space Environment Branch of the Space and Missile Systems Center (SMC SLG/WMLE) have combined efforts to design, develop, test, implement, and validate numerical and graphical products for Air Force Space Command's (AFSPC) Space Environmental Effects Fusion System (SEEFS). These products are generated to analyze, specify, and forecast the effects of the near-earth space environment on Department of Defense weapons, navigation, communications, and surveillance systems. Jointly developed projects that have been completed as prototypes and are undergoing development for real-time operations include a SEEFS architecture and database, five system-impact products, and a high-level decision aid product. This first round of SEEFS products includes the Solar Radio Burst Effects (SoRBE) on radar and satellite communications, Radar Auroral Clutter (RAC), Scintillation Effects on radar and satellite communications (RadScint and SatScint), and Satellite Surface and Deep Charge/Discharge (Char/D) products. This presentation will provide overviews of the current system impact products, along with plans and potentials for future products expected for the SEEFS program. The overviews will include information on applicable research-to-operations (R2O) issues, to include input data coverage and quality control, output confidence levels, modeling standards, and validation efforts.

46 CFR 130.440 - Communications system.

Code of Federal Regulations, 2014 CFR

2014-10-01

... MISCELLANEOUS EQUIPMENT AND SYSTEMS Automation of Unattended Machinery Spaces § 130.440 Communications system. (a) Each OSV must have a communications system to immediately summon a crew member to the machinery... room, and crew accommodations that either— (i) Is a sound-powered telephone; or (ii) Gets its power...

46 CFR 130.440 - Communications system.

Code of Federal Regulations, 2013 CFR

2013-10-01

... MISCELLANEOUS EQUIPMENT AND SYSTEMS Automation of Unattended Machinery Spaces § 130.440 Communications system. (a) Each OSV must have a communications system to immediately summon a crew member to the machinery... room, and crew accommodations that either— (i) Is a sound-powered telephone; or (ii) Gets its power...

46 CFR 130.440 - Communications system.

Code of Federal Regulations, 2011 CFR

2011-10-01

... MISCELLANEOUS EQUIPMENT AND SYSTEMS Automation of Unattended Machinery Spaces § 130.440 Communications system. (a) Each OSV must have a communications system to immediately summon a crew member to the machinery... room, and crew accommodations that either— (i) Is a sound-powered telephone; or (ii) Gets its power...

46 CFR 130.440 - Communications system.

Code of Federal Regulations, 2012 CFR

2012-10-01

... MISCELLANEOUS EQUIPMENT AND SYSTEMS Automation of Unattended Machinery Spaces § 130.440 Communications system. (a) Each OSV must have a communications system to immediately summon a crew member to the machinery... room, and crew accommodations that either— (i) Is a sound-powered telephone; or (ii) Gets its power...

Center for Space Telemetering and Telecommunications Systems, New Mexico State University

NASA Technical Reports Server (NTRS)

Horan, Stephen; DeLeon, Phillip; Borah, Deva; Lyman, Ray

2002-01-01

This viewgraph presentation gives an overview of the Center for Space Telemetering and Telecommunications Systems activities at New Mexico State University. Presentations cover the following topics: (1) small satellite communications, including nanosatellite radio and virtual satellite development; (2) modulation and detection studies, including details on smooth phase interpolated keying (SPIK) spectra and highlights of an adaptive turbo multiuser detector; (3) decoupled approaches to nonlinear ISI compensation; (4) space internet testing; (4) optical communication; (5) Linux-based receiver for lightweight optical communications without a laser in space, including software design, performance analysis, and the receiver algorithm; (6) carrier tracking hardware; and (7) subband transforms for adaptive direct sequence spread spectrum receivers.

Retro-detective control structures for free-space optical communication links.

PubMed

Jin, Xian; Barg, Jason E; Holzman, Jonathan F

2009-12-21

A corner-cube-based retro-detection photocell is introduced. The structure consists of three independent and mutually perpendicular photodiodes (PDs), whose differential photocurrents can be used to probe the alignment state of incident beams. These differential photocurrents are used in an actively-controlled triangulation procedure to optimize the communication channel alignment in a free-space optical (FSO) system. The active downlink and passive uplink communication capabilities of this system are demonstrated.

75 FR 2117 - Privacy Act of 1974; System of Records

Federal Register 2010, 2011, 2012, 2013, 2014

2010-01-14

... Force, 30 Space Communications Squadron, Building 12000, Room 104, 867 Washington Ave., Suite 205... Wing Space Communications Squadron, 867 Washington Avenue, Suite 200-1, Vandenberg Air Force Base... Superintendent, 30 Space Wing Command Post 867 Washington Ave, Suite 205, Vandenberg Air Force Base, California...

Communications satellite systems capacity analysis

NASA Technical Reports Server (NTRS)

Browne, L.; Hines, T.; Tunstall, B.

1982-01-01

Analog and digital modulation techniques are compared with regard to efficient use of the geostationary orbit by communications satellites. Included is the definition of the baseline systems (both space and ground segments), determination of interference susceptibility, calculation of orbit spacing, and evaluation of relative costs. It is assumed that voice or TV is communicated at 14/11 GHz using either FM or QPSK modulation. Both the Fixed-Satellite Service and the Broadcasting-Satellite Service are considered. For most of the cases examined the digital approach requires a satellite spacing less than or equal to that required by the analog approach.

SMC: SCENIC Model Control

NASA Technical Reports Server (NTRS)

Srivastava, Priyaka; Kraus, Jeff; Murawski, Robert; Golden, Bertsel, Jr.

2015-01-01

NASAs Space Communications and Navigation (SCaN) program manages three active networks: the Near Earth Network, the Space Network, and the Deep Space Network. These networks simultaneously support NASA missions and provide communications services to customers worldwide. To efficiently manage these resources and their capabilities, a team of student interns at the NASA Glenn Research Center is developing a distributed system to model the SCaN networks. Once complete, the system shall provide a platform that enables users to perform capacity modeling of current and prospective missions with finer-grained control of information between several simulation and modeling tools. This will enable the SCaN program to access a holistic view of its networks and simulate the effects of modifications in order to provide NASA with decisional information. The development of this capacity modeling system is managed by NASAs Strategic Center for Education, Networking, Integration, and Communication (SCENIC). Three primary third-party software tools offer their unique abilities in different stages of the simulation process. MagicDraw provides UMLSysML modeling, AGIs Systems Tool Kit simulates the physical transmission parameters and de-conflicts scheduled communication, and Riverbed Modeler (formerly OPNET) simulates communication protocols and packet-based networking. SCENIC developers are building custom software extensions to integrate these components in an end-to-end space communications modeling platform. A central control module acts as the hub for report-based messaging between client wrappers. Backend databases provide information related to mission parameters and ground station configurations, while the end user defines scenario-specific attributes for the model. The eight SCENIC interns are working under the direction of their mentors to complete an initial version of this capacity modeling system during the summer of 2015. The intern team is composed of four students in Computer Science, two in Computer Engineering, one in Electrical Engineering, and one studying Space Systems Engineering.

Space Station Information System - Concepts and international issues

NASA Technical Reports Server (NTRS)

Williams, R. B.; Pruett, David; Hall, Dana L.

1987-01-01

The Space Station Information System (SSIS) is outlined in terms of its functions and probable physical facilities. The SSIS includes flight element systems as well as existing and planned institutional systems such as the NASA Communications System, the Tracking and Data Relay Satellite System, and the data and communications networks of the international partners. The SSIS strives to provide both a 'user friendly' environment and a software environment which will allow for software transportability and interoperability across the SSIS. International considerations are discussed as well as project management, software commonality, data communications standards, data security, documentation commonality, transaction management, data flow cross support, and key technologies.

Injection chaining of diode-pumped single-frequency ring lasers for free-space communication

NASA Technical Reports Server (NTRS)

Cheng, E. A. P.; Kane, T. J.; Wallace, R. W.; Cornwell, D. M., Jr.

1991-01-01

A high-power three-stage laser suitable for use in a space communication system has been built. This laser uses three diode-pumped Nd:YAG oscillators coherently combined using the technique of injection chaining. All three oscillators are in one compact and permanently aligned package, and are actively frequency locked to provide CW single frequency output. The three stages provide the redundancy desirable for space communications.

V-band integrated quadriphase modulator

NASA Technical Reports Server (NTRS)

Grote, A.; Chang, K.

1983-01-01

A V-band integrated circuit quadriphase shift keyed modulator/exciter for space communications systems was developed. Intersatellite communications systems require direct modulation at 60 GHz to enhance signal processing capability. For most systems, particularly space applications, small and lightweight components are essential to alleviate severe system design constraints. Thus to achieve wideband, high data rate systems, direct modulation techniques at millimeter waves using solid state integrated circuit technology are an integral part of the overall technology developments.

Introductions to Mission Operations and Ground Data Systems

NASA Technical Reports Server (NTRS)

Stewart, Helen J.

2009-01-01

This slide presentation discusses how in the early concept studies the communications architecture plays an important part: The communications architecture is the arrangement, or configuration of satellites and ground systems in a space system, and the network of communications links that transfers information between them.

Active disturbance rejection controller of fine tracking system for free space optical communication

NASA Astrophysics Data System (ADS)

Cui, Ning; Liu, Yang; Chen, Xinglin; Wang, Yan

2013-08-01

Free space optical communication is one of the best approaches in future communications. Laser beam's acquisition, pointing and tracking are crucial technologies of free space optical communication. Fine tracking system is important component of APT (acquisition, pointing and tracking) system. It cooperates with the coarse pointing system in executing the APT mission. Satellite platform vibration and disturbance, which reduce received optical power, increase bit error rate and affect seriously the natural performance of laser communication. For the characteristic of satellite platform, an active disturbance rejection controller was designed to reduce the vibration and disturbance. There are three major contributions in the paper. Firstly, the effects of vibration on the inter satellite optical communications were analyzed, and the reasons and characters of vibration of the satellite platform were summarized. The amplitude-frequency response of a filter was designed according to the power spectral density of platform vibration of SILEX (Semiconductor Inter-satellite Laser Experiment), and then the signals of platform vibration were generated by filtering white Gaussian noise using the filter. Secondly, the fast steering mirror is a key component of the fine tracking system for optical communication. The mechanical design and model analysis was made to the tip/tilt mirror driven by the piezoelectric actuator and transmitted by the flexure hinge. The transfer function of the fast steering mirror, camera, D/A data acquisition card was established, and the theory model of transfer function of this system was further obtained. Finally, an active disturbance rejection control method is developed, multiple parallel extended state observers were designed for estimation of unknown dynamics and external disturbance, and the estimated states were used for nonlinear feedback control and compensation to improve system performance. The simulation results show that the designed controller not only accurately estimates and compensates the disturbances, but also realizes the robustness to estimation of unknown dynamics. The controller can satisfy the requirement of fine tracking accuracy for free space optical communication system.

Kuipers using communication equipment in the U.S. Laboratory

NASA Image and Video Library

2012-04-24

ISS030-E-250651 (24 April 2012) --- European Space Agency astronaut Andre Kuipers, Expedition 30 flight engineer, uses a communication system near a robotic workstation in the Destiny laboratory of the International Space Station.

Malenchenko uses communication equipment in the SM

NASA Image and Video Library

2008-01-09

ISS016-E-022130 (9 Jan. 2008) --- Cosmonaut Yuri I. Malenchenko, Expedition 16 flight engineer representing Russia's Federal Space Agency, uses a communication system while working in the Zvezda Service Module of the International Space Station.

Malenchenko uses communication equipment in the SM

NASA Image and Video Library

2008-01-09

ISS016-E-022134 (9 Jan. 2008) --- Cosmonaut Yuri I. Malenchenko, Expedition 16 flight engineer representing Russia's Federal Space Agency, uses a communication system while working in the Zvezda Service Module of the International Space Station.

Innovative Methods for the Benefit of Public Health Using Space Technologies for Disaster Response.

PubMed

Dinas, Petros C; Mueller, Christian; Clark, Nathan; Elgin, Tim; Nasseri, S Ali; Yaffe, Etai; Madry, Scott; Clark, Jonathan B; Asrar, Farhan

2015-06-01

Space applications have evolved to play a significant role in disaster relief by providing services including remote sensing imagery for mitigation and disaster damage assessments; satellite communication to provide access to medical services; positioning, navigation, and timing services; and data sharing. Common issues identified in past disaster response and relief efforts include lack of communication, delayed ordering of actions (eg, evacuations), and low levels of preparedness by authorities during and after disasters. We briefly summarize the Space for Health (S4H) Team Project, which was prepared during the Space Studies Program 2014 within the International Space University. The S4H Project aimed to improve the way space assets and experiences are used in support of public health during disaster relief efforts. We recommend an integrated solution based on nano-satellites or a balloon communication system, mobile self-contained relief units, portable medical scanning devices, and micro-unmanned vehicles that could revolutionize disaster relief and disrupt different markets. The recommended new system of coordination and communication using space assets to support public health during disaster relief efforts is feasible. Nevertheless, further actions should be taken by governments and organizations in collaboration with the private sector to design, test, and implement this system.

Coupling efficiency of laser beam to multimode fiber for free space optical communication

NASA Astrophysics Data System (ADS)

Arisa, Suguru; Takayama, Yoshihisa; Endo, Hiroyuki; Shimizu, Ryosuke; Fujiwara, Mikio; Sasaki, Masahide

2017-11-01

Recently, the free space optical (FSO) communications have been widely studied as an alternative for large capacity communications and its possible implementation in satellite and terrestrial laser links. In satellite communications, clouds can strongly attenuate the laser signal that would lead to high bit-error rates or temporal unavailability of the link. To overcome the cloud coverage effects, often site diversity technique is implemented. When using multiple ground stations though, simplified optical system is required to allow the usage of more flexible approaches. In terrestrial laser communications, several methods for optical system simplification by using a multimode fiber (MMF) have been proposed.

Defense Science Board Task Force on Military Satellite Communication and Tactical Networking. Executive Summary

DTIC Science & Technology

2017-03-01

Communications SMC Space and Missile Systems Center SEV Space Enterprise Vision SHF Super High Frequency SINCGARS Single Channel Ground-Air Radio...Appendix D:Acronyms A2/AD Anti-Access/Area Denial ADNS Automated Digital Network System AEHF Advanced Extremely High Frequency AFSPC Air Force Space ...medium-rate modes of defense extremely high frequency (EHF) SATCOM. This reality should be considered a crisis to be dealt with immediately. In

Communicating space weather to policymakers and the wider public

NASA Astrophysics Data System (ADS)

Ferreira, Bárbara

2014-05-01

As a natural hazard, space weather has the potential to affect space- and ground-based technological systems and cause harm to human health. As such, it is important to properly communicate this topic to policymakers and the general public alike, informing them (without being unnecessarily alarmist) about the potential impact of space-weather phenomena and how these can be monitored and mitigated. On the other hand, space weather is related to interesting phenomena on the Sun such as coronal-mass ejections, and incorporates one of the most beautiful displays in the Earth and its nearby space environment: aurora. These exciting and fascinating aspects of space weather should be cultivated when communicating this topic to the wider public, particularly to younger audiences. Researchers have a key role to play in communicating space weather to both policymakers and the wider public. Space scientists should have an active role in informing policy decisions on space-weather monitoring and forecasting, for example. And they can exercise their communication skills by talking about space weather to school children and the public in general. This presentation will focus on ways to communicate space weather to wider audiences, particularly policymakers. It will also address the role researchers can play in this activity to help bridge the gap between the space science community and the public.

Unified tensor model for space-frequency spreading-multiplexing (SFSM) MIMO communication systems

NASA Astrophysics Data System (ADS)

de Almeida, André LF; Favier, Gérard

2013-12-01

This paper presents a unified tensor model for space-frequency spreading-multiplexing (SFSM) multiple-input multiple-output (MIMO) wireless communication systems that combine space- and frequency-domain spreadings, followed by a space-frequency multiplexing. Spreading across space (transmit antennas) and frequency (subcarriers) adds resilience against deep channel fades and provides space and frequency diversities, while orthogonal space-frequency multiplexing enables multi-stream transmission. We adopt a tensor-based formulation for the proposed SFSM MIMO system that incorporates space, frequency, time, and code dimensions by means of the parallel factor model. The developed SFSM tensor model unifies the tensorial formulation of some existing multiple-access/multicarrier MIMO signaling schemes as special cases, while revealing interesting tradeoffs due to combined space, frequency, and time diversities which are of practical relevance for joint symbol-channel-code estimation. The performance of the proposed SFSM MIMO system using either a zero forcing receiver or a semi-blind tensor-based receiver is illustrated by means of computer simulation results under realistic channel and system parameters.

Applying Model Based Systems Engineering to NASA's Space Communications Networks

NASA Technical Reports Server (NTRS)

Bhasin, Kul; Barnes, Patrick; Reinert, Jessica; Golden, Bert

2013-01-01

System engineering practices for complex systems and networks now require that requirement, architecture, and concept of operations product development teams, simultaneously harmonize their activities to provide timely, useful and cost-effective products. When dealing with complex systems of systems, traditional systems engineering methodology quickly falls short of achieving project objectives. This approach is encumbered by the use of a number of disparate hardware and software tools, spreadsheets and documents to grasp the concept of the network design and operation. In case of NASA's space communication networks, since the networks are geographically distributed, and so are its subject matter experts, the team is challenged to create a common language and tools to produce its products. Using Model Based Systems Engineering methods and tools allows for a unified representation of the system in a model that enables a highly related level of detail. To date, Program System Engineering (PSE) team has been able to model each network from their top-level operational activities and system functions down to the atomic level through relational modeling decomposition. These models allow for a better understanding of the relationships between NASA's stakeholders, internal organizations, and impacts to all related entities due to integration and sustainment of existing systems. Understanding the existing systems is essential to accurate and detailed study of integration options being considered. In this paper, we identify the challenges the PSE team faced in its quest to unify complex legacy space communications networks and their operational processes. We describe the initial approaches undertaken and the evolution toward model based system engineering applied to produce Space Communication and Navigation (SCaN) PSE products. We will demonstrate the practice of Model Based System Engineering applied to integrating space communication networks and the summary of its results and impact. We will highlight the insights gained by applying the Model Based System Engineering and provide recommendations for its applications and improvements.

Electronic Subsystems For Laser Communication System

NASA Technical Reports Server (NTRS)

Long, Catherine; Maruschak, John; Patschke, Robert; Powers, Michael

1992-01-01

Electronic subsystems of free-space laser communication system carry digital signals at 650 Mb/s over long distances. Applicable to general optical communications involving transfer of great quantities of data, and transmission and reception of video images of high definition.

Destination-directed, packet-switched architecture for a geostationary communications satellite network

NASA Technical Reports Server (NTRS)

Ivancic, William D.; Shalkhauser, Mary JO; Bobinsky, Eric A.; Soni, Nitin J.; Quintana, Jorge A.; Kim, Heechul; Wager, Paul; Vanderaar, Mark

1993-01-01

A major goal of the Digital Systems Technology Branch at the NASA Lewis Research Center is to identify and develop critical digital components and technologies that either enable new commercial missions or significantly enhance the performance, cost efficiency, and/or reliability of existing and planned space communications systems. NASA envisions a need for low-data-rate, interactive, direct-to-the-user communications services for data, voice, facsimile, and video conferencing. The network would provide enhanced very-small-aperture terminal (VSAT) communications services and be capable of handling data rates of 64 kbps through 2.048 Mbps in 64-kbps increments. Efforts have concentrated heavily on the space segment; however, the ground segment has been considered concurrently to ensure cost efficiency and realistic operational constraints. The focus of current space segment developments is a flexible, high-throughput, fault-tolerant onboard information-switching processor (ISP) for a geostationary satellite communications network. The Digital Systems Technology Branch is investigating both circuit and packet architectures for the ISP. Destination-directed, packet-switched architectures for geostationary communications satellites are addressed.

In-Space Networking On NASA's SCaN Testbed

NASA Technical Reports Server (NTRS)

Brooks, David; Eddy, Wesley M.; Clark, Gilbert J., III; Johnson, Sandra K.

2016-01-01

The NASA Space Communications and Navigation (SCaN) Testbed, an external payload onboard the International Space Station, is equipped with three software defined radios (SDRs) and a programmable flight computer. The purpose of the Testbed is to conduct inspace research in the areas of communication, navigation, and networking in support of NASA missions and communication infrastructure. Multiple reprogrammable elements in the end to end system, along with several communication paths and a semi-operational environment, provides a unique opportunity to explore networking concepts and protocols envisioned for the future Solar System Internet (SSI). This paper will provide a general description of the system's design and the networking protocols implemented and characterized on the testbed, including Encapsulation, IP over CCSDS, and Delay-Tolerant Networking (DTN). Due to the research nature of the implementation, flexibility and robustness are considered in the design to enable expansion for future adaptive and cognitive techniques. Following a detailed design discussion, lessons learned and suggestions for future missions and communication infrastructure elements will be provided. Plans for the evolving research on SCaN Testbed as it moves towards a more adaptive, autonomous system will be discussed.

Vinogradov uses communication equipment in the U.S. Laboratory during Expedition 13

NASA Image and Video Library

2006-04-18

ISS013-E-08059 (18 April 2006) --- Cosmonaut Pavel V. Vinogradov, Expedition 13 commander representing Russia's Federal Space Agency, uses a communication system in the Destiny laboratory of the International Space Station.

Specification for installation of the crew activity planning system coaxial cable communication system

NASA Technical Reports Server (NTRS)

Allen, M. A.; Roman, G. S.

1979-01-01

The specification used to install a broadband coaxial cable communication system to support remote terminal operations on the Crew Activity Planning system at the Lyndon B. Johnson Space Center are reported. The system supports high speed communications between a Harris Slash 8 computer and one or more Sanders Graphic 7 displays.

Taking the Politics Out of Satellite and Space-Based Communications Protocols

NASA Technical Reports Server (NTRS)

Ivancic, William D.

2006-01-01

After many years of studies, experimentation, and deployment, large amounts of misinformation and misconceptions remain regarding applicability of various communications protocols for use in satellite and space-based networks. This paper attempts to remove much of the politics, misconceptions, and misinformation that have plagued spacebased communications protocol development and deployment. This paper provides a common vocabulary for communications; a general discussion of the requirements for various communication environments; an evaluation of tradeoffs between circuit and packet-switching technologies, and the pros and cons of various link, network, transport, application, and security protocols. Included is the applicability of protocol enhancing proxies to NASA, Department of Defense (DOD), and commercial space communication systems.

Beaconless Pointing for Deep-Space Optical Communication

NASA Technical Reports Server (NTRS)

Swank, Aaron J.; Aretskin-Hariton, Eliot; Le, Dzu K.; Sands, Obed S.; Wroblewski, Adam

2016-01-01

Free space optical communication is of interest to NASA as a complement to existing radio frequency communication methods. The potential for an increase in science data return capability over current radio-frequency communications is the primary objective. Deep space optical communication requires laser beam pointing accuracy on the order of a few microradians. The laser beam pointing approach discussed here operates without the aid of a terrestrial uplink beacon. Precision pointing is obtained from an on-board star tracker in combination with inertial rate sensors and an outgoing beam reference vector. The beaconless optical pointing system presented in this work is the current approach for the Integrated Radio and Optical Communication (iROC) project.

Use of low orbital satellite communications systems for humanitarian programs

NASA Technical Reports Server (NTRS)

Vlasov, Vladimir N.; Gorkovoy, Vladimir

1991-01-01

Communication and information exchange play a decisive role in progress and social development. However, in many parts of the world the communication infrastructure is inadequate and the capacity for on-line exchange of information may not exist. This is true of underdeveloped countries, remote and relatively inaccessible regions, sites of natural disasters, and of all cases where the resources needed to create complex communication systems are limited. The creation of an inexpensive space communications system to service such areas is therefore a high priority task. In addition to a relatively low-cost space segment, an inexpensive space communications systems requires a large number of ground terminals, which must be relatively inexpensive, energy efficient (using power generated by storage batteries, or solar arrays, etc.), small in size, and must not require highly expert maintenance. The ground terminals must be portable, and readily deployable. Communications satellites in geostationary orbit at altitudes of about 36,000 km are very expensive and require complex and expensive ground stations and launch vehicles. Given current technology, it is categorically impossible to develop inexpensive satellite systems with portable ground terminals using such satellites. To solve the problem of developing an inexpensive satellite communications system that can operate with relatively small ground stations, including portable terminals, we propose to use a system with satellites in low Earth orbit, at an altitude of 900-1500 km. Because low orbital satellites are much closer to the Earth than geostationary ones and require vastly less energy expenditure by the satellite and ground terminals for transmission of messages, a system using them is relatively inexpensive. Such a system could use portable ground terminals no more complex than ordinary mobile police radios.

A review of gallium nitride LEDs for multi-gigabit-per-second visible light data communications

NASA Astrophysics Data System (ADS)

Rajbhandari, Sujan; McKendry, Jonathan J. D.; Herrnsdorf, Johannes; Chun, Hyunchae; Faulkner, Grahame; Haas, Harald; Watson, Ian M.; O'Brien, Dominic; Dawson, Martin D.

2017-02-01

The field of visible light communications (VLC) has gained significant interest over the last decade, in both fibre and free-space embodiments. In fibre systems, the availability of low cost polymer optical fibre (POF) that is compatible with visible data communications has been a key enabler. In free-space applications, the availability of hundreds of THz of the unregulated spectrum makes VLC attractive for wireless communications. This paper provides an overview of the recent developments in VLC systems based on gallium nitride (GaN) light-emitting diodes (LEDs), covering aspects from sources to systems. The state-of-the-art technology enabling bandwidth of GaN LEDs in the range of >400 MHz is explored. Furthermore, advances in key technologies, including advanced modulation, equalisation, and multiplexing that have enabled free-space VLC data rates beyond 10 Gb s-1 are also outlined.

Research and technology: Fiscal year 1984 report

NASA Technical Reports Server (NTRS)

1985-01-01

Topics covered include extraterrestrial physics, high energy astrophysics, astronomy, solar physics, atmospheres, oceans, terrestrial physics, space technology, sensors, techniques, user space data systems, space communications and navigation, and system and software engineering.

Communications and Tracking Distributed Systems Evolution Study

NASA Technical Reports Server (NTRS)

Culpepper, William

1990-01-01

The Communications and Tracking (C & T) techniques and equipment to support evolutionary space station concepts are being analyzed. Evolutionary space station configurations and operational concepts are used to derive the results to date. A description of the C & T system based on future capability needs is presented. Included are the hooks and scars currently identified to support future growth.

Study of efficient video compression algorithms for space shuttle applications

NASA Technical Reports Server (NTRS)

Poo, Z.

1975-01-01

Results are presented of a study on video data compression techniques applicable to space flight communication. This study is directed towards monochrome (black and white) picture communication with special emphasis on feasibility of hardware implementation. The primary factors for such a communication system in space flight application are: picture quality, system reliability, power comsumption, and hardware weight. In terms of hardware implementation, these are directly related to hardware complexity, effectiveness of the hardware algorithm, immunity of the source code to channel noise, and data transmission rate (or transmission bandwidth). A system is recommended, and its hardware requirement summarized. Simulations of the study were performed on the improved LIM video controller which is computer-controlled by the META-4 CPU.

International standards for optical wireless communications: state-of-the-art and future directions

NASA Astrophysics Data System (ADS)

Marciniak, Marian

2017-10-01

As the number of active OWC installations is growing fast, the standards for compatibility of co-existing neighbouring systems are being developed. The paper addresses the Laser Safety (IEC standards), ITU-T Study Group 15 standards (G.640 Co-location longitudinally compatible interfaces for free space optical systems), ITU-Radiocommunication Sector standards (P.1817-1 Propagation data required for the design of terrestrial free-space optical links), and the IEEE Work in Progress - standardization activity on Visible Light Communications. International standards of FSO communications have been reviewed and discussed. ITU, IEC, and IEEE International standards for Free-Space Optical links have been reviewed. The system reliability and availability as well as security issues will be addressed as well in the talk.

ITC/USA/'82; Proceedings of the International Telemetering Conference, San Diego, CA, September 28-30, 1982

NASA Astrophysics Data System (ADS)

The topics studied are related to customer-designed integrated circuits and silicon foundries, systems applications, recent developments in airborne telemetry hardware, optical communications, theoretical applications, stored data systems, digital communications-satellites and other systems, antenna systems and technology, the AF satellite control network, modems, telemetry standards, NASA Deep Space Network operations, and modems applicable to range telemetry and range data relay. Aspects of communication interoperability and transmission standards are considered along with subjects of magnetic tape rec/rep theory and technology, a satellite command and control panel, a computer automated ground station, STS communications, cryptography, RF systems, sensor unique data recovery techniques, software applications, multiplexer-demuliplexer, microprocessor applications, and communication relays. Attention is given to the U.S. Federal data encryption standard (DES), the impact of channel errors on data compression, the effect of premodulation filters on bit error rate performance, and power efficient optical communications for space applications. For individual items see A84-32402 to A84-32456

Intuitive Tools for the Design and Analysis of Communication Payloads for Satellites

NASA Technical Reports Server (NTRS)

Culver, Michael R.; Soong, Christine; Warner, Joseph D.

2014-01-01

In an effort to make future communications satellite payload design more efficient and accessible, two tools were created with intuitive graphical user interfaces (GUIs). The first tool allows payload designers to graphically design their payload by using simple drag and drop of payload components onto a design area within the program. Information about each picked component is pulled from a database of common space-qualified communication components sold by commerical companies. Once a design is completed, various reports can be generated, such as the Master Equipment List. The second tool is a link budget calculator designed specifically for ease of use. Other features of this tool include being able to access a database of NASA ground based apertures for near Earth and Deep Space communication, the Tracking and Data Relay Satellite System (TDRSS) base apertures, and information about the solar system relevant to link budget calculations. The link budget tool allows for over 50 different combinations of user inputs, eliminating the need for multiple spreadsheets and the user errors associated with using them. Both of the aforementioned tools increase the productivity of space communication systems designers, and have the colloquial latitude to allow non-communication experts to design preliminary communication payloads.

System concepts and design examples for optical communication with planetary spacecraft

NASA Astrophysics Data System (ADS)

Lesh, James R.

Systems concepts for optical communication with future deep-space (planetary) spacecraft are described. These include not only the optical transceiver package aboard the distant spacecraft, but the earth-vicinity optical-communications receiving station as well. Both ground-based, and earth-orbiting receivers are considered. Design examples for a number of proposed or potential deep-space missions are then presented. These include an orbital mission to Saturn, a Lander and Rover mission to Mars, and an astronomical mission to a distance of 1000 astronomical units.

Communications and Intelligent Systems Division Overview

NASA Technical Reports Server (NTRS)

Emerson, Dawn

2016-01-01

This presentation provides an overview of the research and engineering in the competency fieldsof advanced communications and intelligent systems with emphasis on advanced technologies, architecture definitionand system development for application in current and future aeronautics and space systems.

Optical satellite communications in Europe

NASA Astrophysics Data System (ADS)

Sodnik, Zoran; Lutz, Hanspeter; Furch, Bernhard; Meyer, Rolf

2010-02-01

This paper describes optical satellite communication activities based on technology developments, which started in Europe more than 30 years ago and led in 2001 to the world-first optical inter-satellite communication link experiment (SILEX). SILEX proved that optical communication technologies can be reliably mastered in space and in 2006 the Japanese Space Agency (JAXA) joined the optical inter-satellite experiment from their own satellite. Since 2008 the German Space Agency (DLR) is operating an inter-satellite link between the NFIRE and TerraSAR-X satellites based on a second generation of laser communication technology, which will be used for the new European Data Relay Satellite (EDRS) system to be deployed in 2013.

Re-engineering NASA's space communications to remain viable in a constrained fiscal environment

NASA Astrophysics Data System (ADS)

Hornstein, Rhoda Shaller; Hei, Donald J., Jr.; Kelly, Angelita C.; Lightfoot, Patricia C.; Bell, Holland T.; Cureton-Snead, Izeller E.; Hurd, William J.; Scales, Charles H.

1994-11-01

Along with the Red and Blue Teams commissioned by the NASA Administrator in 1992, NASA's Associate Administrator for Space Communications commissioned a Blue Team to review the Office of Space Communications (Code O) Core Program and determine how the program could be conducted faster, better, and cheaper. Since there was no corresponding Red Team for the Code O Blue Team, the Blue Team assumed a Red Team independent attitude and challenged the status quo, including current work processes, functional distinctions, interfaces, and information flow, as well as traditional management and system development practices. The Blue Team's unconstrained, non-parochial, and imaginative look at NASA's space communications program produced a simplified representation of the space communications infrastructure that transcends organizational and functional boundaries, in addition to existing systems and facilities. Further, the Blue Team adapted the 'faster, better, cheaper' charter to be relevant to the multi-mission, continuous nature of the space communications program and to serve as a gauge for improving customer services concurrent with achieving more efficient operations and infrastructure life cycle economies. This simplified representation, together with the adapted metrics, offers a future view and process model for reengineering NASA's space communications to remain viable in a constrained fiscal environment. Code O remains firm in its commitment to improve productivity, effectiveness, and efficiency. In October 1992, the Associate Administrator reconstituted the Blue Team as the Code O Success Team (COST) to serve as a catalyst for change. In this paper, the COST presents the chronicle and significance of the simplified representation and adapted metrics, and their application during the FY 1993-1994 activities.

Re-engineering NASA's space communications to remain viable in a constrained fiscal environment

NASA Technical Reports Server (NTRS)

Hornstein, Rhoda Shaller; Hei, Donald J., Jr.; Kelly, Angelita C.; Lightfoot, Patricia C.; Bell, Holland T.; Cureton-Snead, Izeller E.; Hurd, William J.; Scales, Charles H.

1994-01-01

Along with the Red and Blue Teams commissioned by the NASA Administrator in 1992, NASA's Associate Administrator for Space Communications commissioned a Blue Team to review the Office of Space Communications (Code O) Core Program and determine how the program could be conducted faster, better, and cheaper. Since there was no corresponding Red Team for the Code O Blue Team, the Blue Team assumed a Red Team independent attitude and challenged the status quo, including current work processes, functional distinctions, interfaces, and information flow, as well as traditional management and system development practices. The Blue Team's unconstrained, non-parochial, and imaginative look at NASA's space communications program produced a simplified representation of the space communications infrastructure that transcends organizational and functional boundaries, in addition to existing systems and facilities. Further, the Blue Team adapted the 'faster, better, cheaper' charter to be relevant to the multi-mission, continuous nature of the space communications program and to serve as a gauge for improving customer services concurrent with achieving more efficient operations and infrastructure life cycle economies. This simplified representation, together with the adapted metrics, offers a future view and process model for reengineering NASA's space communications to remain viable in a constrained fiscal environment. Code O remains firm in its commitment to improve productivity, effectiveness, and efficiency. In October 1992, the Associate Administrator reconstituted the Blue Team as the Code O Success Team (COST) to serve as a catalyst for change. In this paper, the COST presents the chronicle and significance of the simplified representation and adapted metrics, and their application during the FY 1993-1994 activities.

Vinogradov reconfigures communication in the SM during Expedition 13

NASA Image and Video Library

2006-04-26

ISS013-E-10238 (26 April 2006) --- Cosmonaut Pavel V. Vinogradov, Expedition 13 commander representing Russia's Federal Space Agency, uses a communication system while working with equipment in the Zvezda Service Module of the International Space Station.

Forecast of space shuttle flight requirements for launch of commercial communications satellites

NASA Technical Reports Server (NTRS)

1977-01-01

The number of communication satellites required over the next 25 years to support domestic and regional communication systems for telephony, telegraphy and other low speed data; video teleconferencing, new data services, direct TV broadcasting; INTELSAT; and maritime and aeronautical services was estimated to determine the number of space shuttle flights necessary for orbital launching.

Connectivity services based on optical ground-to-space links

NASA Astrophysics Data System (ADS)

Knopp, Marcus T.; Giggenbach, Dirk; Mata Calvo, Ramon; Fuchs, Christian; Saucke, Karen; Heine, Frank; Sellmaier, Florian; Huber, Felix

2018-07-01

Repeater systems in a geostationary orbit utilizing free-space optical-communication offer great potential to backup, process and archive large amounts of data collected or generated at remote locations. In contrast to existing or upcoming global satellite communication systems, such optical GEO relays are able to provide a huge return-channel data throughput with channel rates in the gigabit-per-second range. One of the most critical aspects of such data uplinks are atmospheric disturbances above the optical ground terminals used to connect to the space segment. In this study, we analyse the design drivers of optical ground stations for land-based applications. In particular, the effects of atmospheric attenuation and atmospheric turbulence are investigated. Moreover, we present implementation ideas of the necessary ground infrastructure and exemplify our results in a case study on the applicability of free-space optical satellite communication to the radio astronomy community. Our survey underpins pre-existing ventures to foster optical relay services like the Space-Data-Highway operating via the European Data Relay System. With well-designed, self-sufficient and small-sized ground terminals new user groups could be attracted, by offering alternatives to the emerging LEO mega-constellations and GEO-satellite communication systems, which operate at low return channel data rates across-the-board.

A Day in the Life of the Laser Communications Relay Demonstration Project

NASA Technical Reports Server (NTRS)

Edwards, Bernard; Israel, David; Caroglanian, Armen; Spero, James; Roberts, Tom; Moores, John

2016-01-01

This paper provides an overview of the planned concept of operations for the Laser Communications Relay Demonstration Project (LCRD), a joint project among NASA's Goddard Space Flight Center (GSFC), the Jet Propulsion Laboratory, California Institute of Technology (JPL), and the Massachusetts Institute of Technology Lincoln Laboratory (MIT/LL). LCRD will provide at least two years of bi-directional optical communications at user data rates of up to 1.244 Gbps in an operational environment. The project lays the groundwork for establishing communications architecture and protocols, and developing the communications hardware and support infrastructure, concluding in a demonstration of optical communications' potential to meet NASA's growing need for higher data rates for future science and exploration missions. A pair of flight optical communications terminals will reside on a single commercial communications satellite in geostationary orbit; the two ground optical communications terminals will be located in Southern California and Hawaii. This paper summarizes the current LCRD architecture and key systems for the demonstration, focusing on what it will take to operate an optical communications relay that can support space-to-space, space-to-air, and space-to-ground optical links.

A Day in the Life of the Laser Communications Relay Demonstration (LCRD) Project.

NASA Technical Reports Server (NTRS)

Israel, David; Caroglanian, Armen; Edwards, Bernard; Spero, James; Roberts, Tom; Moores, John

2016-01-01

This presentation provides an overview of the planned concept of operations for the Laser Communications Relay Demonstration Project (LCRD), a joint project among NASA's Goddard Space Flight Center (GSFC), the Jet Propulsion Laboratory, California Institute of Technology (JPL), and the Massachusetts Institute of Technology Lincoln Laboratory (MITLL). LCRD will provide at least two years of bi-directional optical communications at user data rates of up to 1.244 Gbps in an operational environment. The project lays the ground work for establishing communications architecture and protocols, and developing the communications hardware and support infrastructure, concluding in a demonstration of optical communications potential to meet NASAs growing need for higher data rates for future science and exploration missions. A pair of flight optical communications terminals will reside on a single commercial communications satellite in geostationary orbit; the two ground optical communications terminals will be located in Southern California and Hawaii. This paper summarizes the current LCRD architecture and key systems for the demonstration, focusing on what it will take to operate an optical communications relay that can support space-to-space, space-to-air, and space-to-ground optical links.

Wavelength division multiplexing of chaotic secure and fiber-optic communications.

PubMed

Zhang, Jian-Zhong; Wang, An-Bang; Wang, Juan-Fen; Wang, Yun-Cai

2009-04-13

Wavelength division multiplexing (WDM) transmission of chaotic optical communication (COC) and conventional fiber-optic communication (CFOC) is numerically confirmed and analyzed. For an 80-km-long two-channel communication system, a 1-Gb/s secure message in COC channel and 10-Gb/s digital signal in CFOC channel are simultaneously achieved with 100 GHz channel spacing. Our numerical simulations demonstrate that the COC and CFOC can realize no-crosstalk transmission of 80 km when the peak power of CFOC channel is less than 8dBm. We also find that the crosstalk between COC and CFOC does not depend on channel spacing when the channel spacing exceeds 100GHz. Moreover, the crosstalk does not limit channel number by comparing the synchronization performance of COC in four- and six-channel WDM systems.

Astronomy. Laser telemetry from space.

PubMed

Bland-Hawthorn, Joss; Harwit, Alex; Harwit, Martin

2002-07-26

Space missions currently on the drawing boards are expected to gather data at rates exceeding the transmission capabilities of today's telemetry systems by many orders of magnitude. Even on current missions, onboard data compression techniques are being implemented to compensate for lack of transmission speed. But while data compression can minimize the loss of data, it is no substitute for transmitting all of the data through a faster communications link. The transmission problem will soon reach crisis proportions and will affect astronomical, Earth resources, geophysical, meteorological, planetary and other space science missions. To overcome this communications bottleneck, the authors advocate the implementation of telemetry systems based on near-infrared laser transmission techniques. The fiber-optics communications industry has developed most of the basic components required for signal transmission in this wavelength band, which should make such a system affordable on scales relevant to the cost of anticipated space science missions.

The Telecommunications and Data Acquisition Report. [Deep Space Network

NASA Technical Reports Server (NTRS)

Posner, E. C. (Editor)

1988-01-01

In space communications, radio navigation, radio science, and ground based radio and radar astronomy, activities of the Deep Space Network and its associated Ground Communications Facility in planning, in supporting research and technology, in implementation, and in operations are reported. Also included is TDA funded activity at JPL on data and information systems and reimbursable DSN work performed for other space agencies through NASA.

Launch Processing System. [for Space Shuttle

NASA Technical Reports Server (NTRS)

Byrne, F.; Doolittle, G. V.; Hockenberger, R. W.

1976-01-01

This paper presents a functional description of the Launch Processing System, which provides automatic ground checkout and control of the Space Shuttle launch site and airborne systems, with emphasis placed on the Checkout, Control, and Monitor Subsystem. Hardware and software modular design concepts for the distributed computer system are reviewed relative to performing system tests, launch operations control, and status monitoring during ground operations. The communication network design, which uses a Common Data Buffer interface to all computers to allow computer-to-computer communication, is discussed in detail.

MiniAERCam Ranging

NASA Technical Reports Server (NTRS)

Talley, Tom

2003-01-01

Johnson Space Center (JSC) is designing a small, remotely controlled vehicle that will carry two color and one black and white video cameras in space. The device will launch and retrieve from the Space Vehicle and be used for remote viewing. Off the shelf cellular technology is being used as the basis for communication system design. Existing plans include using multiple antennas to make simultaneous estimates of the azimuth of the MiniAERCam from several sites on the Space Station and use triangulation to find the location of the device. Adding range detection capability to each of the nodes on the Space Vehicle would allow an estimate of the location of the MiniAERCam to be made at each Communication And Telemetry Box (CATBox) independent of all the other communication nodes. This project will investigate the techniques used by the Global Positioning System (GPS) to achieve accurate positioning information and adapt those strategies that are appropriate to the design of the CATBox range determination system.

The 30/20 GHz flight experiment system, phase 2. Volume 1: Executive summary

NASA Technical Reports Server (NTRS)

Bronstein, L.; Kawamoto, Y.; Ribarich, J. J.; Scope, J. R.; Forman, B. J.; Bergman, S. G.; Reisenfeld, S.

1981-01-01

Summary information on the final communication system design, communication payload, space vehicle, and development plan for the 30/20 GHz flight experiment will be installed on the LEASAT spacecraft which will be placed into orbit from the space shuttle cargo bay. The communication concept has two parts: a truck service and a customer premise service (CPS). The trucking system serves four spot beams which are interconnected in a satellite switched time division multiple access mode by an IF switch matrix. The CPS covers two large areas of the eastern United States with a pair of scanning beams.

Research and technology, 1988

NASA Technical Reports Server (NTRS)

1988-01-01

Flight projects and mission definition studies for 1988 are briefly described. Technology research is presented in the following areas: sensors and space technology; space communication systems; system and software engineering; user space data systems; and techniques. Studies are presented for the following space and Earth science areas: atmospheres, SN 1987A, astronomy, high energy astrophysics, land and climate, solar systems, and oceans.

Crew/computer communications study. Volume 1: Final report. [onboard computerized communications system for spacecrews

NASA Technical Reports Server (NTRS)

Johannes, J. D.

1974-01-01

Techniques, methods, and system requirements are reported for an onboard computerized communications system that provides on-line computing capability during manned space exploration. Communications between man and computer take place by sequential execution of each discrete step of a procedure, by interactive progression through a tree-type structure to initiate tasks or by interactive optimization of a task requiring man to furnish a set of parameters. Effective communication between astronaut and computer utilizes structured vocabulary techniques and a word recognition system.

Space Station needs, attributes and architectural options. Volume 2, book 2, part 2, Task 2: Information management system

NASA Technical Reports Server (NTRS)

1983-01-01

Missions to be performed, station operations and functions to be carried out, and technologies anticipated during the time frame of the space station were examined in order to determine the scope of the overall information management system for the space station. This system comprises: (1) the data management system which includes onboard computer related hardware and software required to assume and exercise control of all activities performed on the station; (2) the communication system for both internal and external communications; and (3) the ground segment. Techniques used to examine the information system from a functional and performance point of view are described as well as the analyses performed to derive the architecture of both the onboard data management system and the system for internal and external communications. These architectures are then used to generate a conceptual design of the onboard elements in order to determine the physical parameters (size/weight/power) of the hardware and software. The ground segment elements are summarized.

Space Station needs, attributes and architectural options. Volume 2, book 2, part 2, Task 2: Information management system

NASA Astrophysics Data System (ADS)

1983-04-01

Missions to be performed, station operations and functions to be carried out, and technologies anticipated during the time frame of the space station were examined in order to determine the scope of the overall information management system for the space station. This system comprises: (1) the data management system which includes onboard computer related hardware and software required to assume and exercise control of all activities performed on the station; (2) the communication system for both internal and external communications; and (3) the ground segment. Techniques used to examine the information system from a functional and performance point of view are described as well as the analyses performed to derive the architecture of both the onboard data management system and the system for internal and external communications. These architectures are then used to generate a conceptual design of the onboard elements in order to determine the physical parameters (size/weight/power) of the hardware and software. The ground segment elements are summarized.

An Update on the CCSDS Optical Communications Working Group

NASA Technical Reports Server (NTRS)

Edwards, Bernard L.; Schulz, Klaus-Juergen; Hamkins, Jonathan; Robinson, Bryan; Alliss, Randall; Daddato, Robert; Schmidt, Christopher; Giggebach, Dirk; Braatz, Lena

2017-01-01

International space agencies around the world are currently developing optical communication systems for Near Earth and Deep Space applications for both robotic and human rated spacecraft. These applications include both links between spacecraft and links between spacecraft and ground. The Interagency Operation Advisory Group (IOAG) has stated that there is a strong business case for international cross support of spacecraft optical links. It further concluded that in order to enable cross support the links must be standardized. This paper will overview the history and structure of the space communications international standards body, the Consultative Committee for Space Data Systems (CCSDS), that will develop the standards and provide an update on the proceedings of the Optical Communications Working Group within CCSDS. This paper will also describe the set of optical communications standards being developed and outline some of the issues that must be addressed in the next few years. The paper will address in particular the ongoing work on application scenarios for deep space to ground called High Photon Efficiency, for LEO to ground called Low Complexity, for inter-satellite and near Earth to ground called High Data Rate, as well as associated atmospheric measurement techniques and link operations concepts.

Radio-wave propagation for space communications systems

NASA Technical Reports Server (NTRS)

Ippolito, L. J.

1981-01-01

The most recent information on the effects of Earth's atmosphere on space communications systems is reviewed. The design and reliable operation of satellite systems that provide the many applications in space which rely on the transmission of radio waves for communications and scientific purposes are dependent on the propagation characteristics of the transmission path. The presence of atmospheric gases, clouds, fog, precipitation, and turbulence causes uncontrolled variations in the signal characteristics. These variations can result in a reduction of the quality and reliability of the transmitted information. Models and other techniques are used in the prediction of atmospheric effects as influenced by frequency, geography, elevation angle, and type of transmission. Recent data on performance characteristics obtained from direct measurements on satellite links operating to above 30 GHz have been reviewed. Particular emphasis has been placed on the effects of precipitation on the Earth/space path, including rain attenuation, and ice particle depolarization. Other factors are sky noise, antenna gain degradation, scintillations, and bandwidth coherence. Each of the various propagation factors has an effect on design criteria for communications systems. These criteria include link reliability, power margins, noise contribution, modulation and polarization factors, channel cross talk, error rate, and bandwidth limitations.

Laser Communication Experiments with Artemis Satellite

NASA Astrophysics Data System (ADS)

Kuzkov, Sergii; Sodnik, Zoran; Kuzkov, Volodymyr

2013-10-01

In November 2001, the European Space Agency (ESA) established the world-first inter-satellite laser communication link between the geostationary ARTEMIS satellite and the low Earth orbiting (LEO) SPOT-4 Earth observation satellite, demonstrating data rates of 50 Mbps. In 2006, the Japanese Space Agency launched the KIRARI (OICETS) LEO satellite with a compatible laser communication terminal and bidirectional laser communication links (50 Mbps and 2 Mbps) were successfully realized between KIRARI and ARTEMIS. ESA is now developing the European Data Relay Satellite (EDRS) system, which will use laser communication technology to transmit data between the Sentinel 1 and 2 satellites in LEO to two geostationary satellites (EDRS-A and EDRS-C) at data rates of 1.8 Gbps. As the data handling capabilities of state-of-the-art telecommunication satellites in GEO increase so is the demand for the feeder-link bandwidth to be transmitted from ground. This is why there is an increasing interest in developing high bandwidth ground-to-space laser communication systems working through atmosphere. In 2002, the Main Astronomical Observatory (MAO) started the development of its own laser communication system for its 0.7m AZT-2 telescope, located in Kyiv, Ukraine. The work was supported by the National Space Agency of Ukraine and by ESA. MAO developed a highly accurate computerized tracking system for AZT-2 telescope and a compact laser communication package called LACES (Laser Atmosphere and Communication Experiments with Satellites). The LACES instrument includes a camera of the pointing and tracking subsystems, a receiver module, a laser transmitter module, a tip/tilt atmospheric turbulence compensation subsystem, a bit error rate tester module and other optical and electronic components. The principal subsystems are mounted on a platform, which is located at the Cassegrain focus of the AZT-2 telescope. All systems were tested with the laser communication payload on-board ARTEMIS and the data analysis was supported by the telemetry received from the ARTEMIS payload control centre in Redu (Belgium). Special attention was focused on the investigation of the impact of atmosphere turbulence on laser beam propagation, especially in cloudy conditions. A description of our telescope and ground based laser system as well as the experimental results will be presented.

The Telecommunications and Data Acquisition Report

NASA Technical Reports Server (NTRS)

Yuen, Joseph H. (Editor)

1995-01-01

This quarterly publiction provides archival reports on developments in programs managed by JPL Telecommunications and Mission Operations Directorate (TMOD), which now includes the former communications and Data Acquisition (TDA) Office. In space communications, radio navigation, radio science, and ground-based radio and radar astronomy, it reports on activities of the Deep Space Network (DSN) in planning, supporting research and technology, implementation, and operations. Also included are standards activity at JPL for space data and information systems and reimbursable DSN work performed for other space agencies through NASA. The Orbital Debris Radar Program, funded by the Office of Space Systems Development, makes use of the planetary radar capability when the antennas are configured at science instruments making direct observations of planets, their satellites, and asteroids of our solar system.

Optoelectronics research for communication programs at the Goddard Space Flight Center

NASA Technical Reports Server (NTRS)

Krainak, Michael A.

1991-01-01

Current optoelectronics research and development of high-power, high-bandwidth laser transmitters, high-bandwidth, high-sensitivity optical receivers, pointing, acquisition and tracking components, and experimental and theoretical system modeling at the NASA Goddard Space Flight Center is reviewed. Program hardware and space flight milestones are presented. It is believed that these experiments will pave the way for intersatellite optical communications links for both the NASA Advanced Tracking and Data Relay Satellite System and commercial users in the 21st century.

Coding for reliable satellite communications

NASA Technical Reports Server (NTRS)

Gaarder, N. T.; Lin, S.

1986-01-01

This research project was set up to study various kinds of coding techniques for error control in satellite and space communications for NASA Goddard Space Flight Center. During the project period, researchers investigated the following areas: (1) decoding of Reed-Solomon codes in terms of dual basis; (2) concatenated and cascaded error control coding schemes for satellite and space communications; (3) use of hybrid coding schemes (error correction and detection incorporated with retransmission) to improve system reliability and throughput in satellite communications; (4) good codes for simultaneous error correction and error detection, and (5) error control techniques for ring and star networks.

A note on deep space optical communication link parameters

NASA Technical Reports Server (NTRS)

Dolinar, S. J.; Yuen, J. H.

1982-01-01

Topical communication in the context of a deep space communication link. Communication link analysis at the optical frequencies differs significantly from that at microwave frequencies such as the traditional S and X-bands used in deep space applications, due to the different technology of transmitter, antenna, modulators, and receivers. In addition, the important role of quantum noise in limiting system performance is quite different than that of thermal noise. The optical link design is put in a design control table format similar to a microwave telecom link design. Key considerations unique to the optical link are discussed.

Passive Thermal Design Approach for the Space Communications and Navigation (SCaN) Testbed Experiment on the International Space Station (ISS)

NASA Technical Reports Server (NTRS)

Siamidis, John; Yuko, Jim

2014-01-01

The Space Communications and Navigation (SCaN) Program Office at NASA Headquarters oversees all of NASAs space communications activities. SCaN manages and directs the ground-based facilities and services provided by the Deep Space Network (DSN), Near Earth Network (NEN), and the Space Network (SN). Through the SCaN Program Office, NASA GRC developed a Software Defined Radio (SDR) testbed experiment (SCaN testbed experiment) for use on the International Space Station (ISS). It is comprised of three different SDR radios, the Jet Propulsion Laboratory (JPL) radio, Harris Corporation radio, and the General Dynamics Corporation radio. The SCaN testbed experiment provides an on-orbit, adaptable, SDR Space Telecommunications Radio System (STRS) - based facility to conduct a suite of experiments to advance the Software Defined Radio, Space Telecommunications Radio Systems (STRS) standards, reduce risk (Technology Readiness Level (TRL) advancement) for candidate Constellation future space flight hardware software, and demonstrate space communication links critical to future NASA exploration missions. The SCaN testbed project provides NASA, industry, other Government agencies, and academic partners the opportunity to develop and field communications, navigation, and networking technologies in the laboratory and space environment based on reconfigurable, software defined radio platforms and the STRS Architecture.The SCaN testbed is resident on the P3 Express Logistics Carrier (ELC) on the exterior truss of the International Space Station (ISS). The SCaN testbed payload launched on the Japanese Aerospace Exploration Agency (JAXA) H-II Transfer Vehicle (HTV) and was installed on the ISS P3 ELC located on the inboard RAM P3 site. The daily operations and testing are managed out of NASA GRC in the Telescience Support Center (TSC).

Use of IPsec by Manned Space Missions

NASA Technical Reports Server (NTRS)

Pajevski, Michael J.

2009-01-01

NASA's Constellation Program is developing its next generation manned space systems for missions to the International Space Station (ISS) and the Moon. The Program is embarking on a path towards standards based Internet Protocol (IP) networking for space systems communication. The IP based communications will be paired with industry standard security mechanisms such as Internet Protocol Security (IPsec) to ensure the integrity of information exchanges and prevent unauthorized release of sensitive information in-transit. IPsec has been tested in simulations on the ground and on at least one Earth orbiting satellite, but the technology is still unproven in manned space mission situations and significant obstacles remain.

The Space Mobile Network

NASA Technical Reports Server (NTRS)

Israel, David

2017-01-01

The definition and development of the next generation space communications and navigation architecture is underway. The primary goals are to remove communications and navigations constraints from missions and to enable increased autonomy. The Space Mobile Network (SMN) is an architectural concept that includes new technology and operations that will provide flight systems with an similar user experience to terrestrial wireless mobile networks. This talk will describe the SMN and its proposed new features, such as Disruption Tolerant Networking (DTN), optical communications, and User Initiated Services (UIS).

The Laser Communications Relay and the Path to the Next Generation Near Earth Relay

NASA Technical Reports Server (NTRS)

Israel, David J.

2015-01-01

NASA Goddard Space Flight Center is currently developing the Laser Communications Relay Demonstration (LCRD) as a Path to the Next Generation Near Earth Space Communication Network. The current NASA Space Network or Tracking and Data Relay Satellite System is comprised of a constellation of Tracking and Data Relay Satellites (TDRS) in geosynchronous orbit and associated ground stations and operation centers. NASA is currently targeting a next generation of relay capability on orbit in the 2025 timeframe.

Inter-satellites x-ray communication system

NASA Astrophysics Data System (ADS)

Mou, Huan; Li, Bao-quan

2017-02-01

An inter-satellite X-ray communication system is presented in this paper. X-ray has a strong penetrating power without almost attenuation for transmission in outer space when the energy of X-ray photons is more than 10KeV and the atmospheric pressure is lower than 10-1 Pa, so it is convincing of x-ray communication in inter-satellite communication and deep space exploration. Additionally, using X-ray photons as information carriers can be used in some communication applications that laser communication and radio frequency (RF) communication are not available, such as ionization blackout area communication. The inter-satellites X-ray communication system, including the grid modulated X-ray source, the high-sensitivity X-ray detector and the transmitting and receiving antenna, is described explicitly. As the X-ray transmitter, a vacuum-sealed miniature modulated X-ray source has been fabricated via the single-step brazing process in a vacuum furnace. Pulse modulation of X-rays, by means of controlling the voltage value of the grid electrode, is realized. Three focusing electrodes, meanwhile, are used to make the electron beam converge and finally 150μm focusing spot diameter is obtained. The X-ray detector based on silicon avalanche photodiodes (APDs) is chosen as the communication receiver on account of its high temporal resolution and non-vacuum operating environment. Furthermore, considering x-ray emission characteristic and communication distance of X-rays, the multilayer nested rotary parabolic optics is picked out as transmitting and receiving antenna. And as a new concept of the space communication, there will be more important scientific significance and application prospects, called "Next-Generation Communications".

Near Earth Architectural Options for a Future Deep Space Optical Communications Network

NASA Technical Reports Server (NTRS)

Edwards, B. L.; Liebrecht, P. E.; Fitzgerald, R. J.

2004-01-01

In the near future the National Aeronautics and Space Administration anticipates a significant increase in demand for long-haul communications services from deep space to Earth. Distances will range from 0.1 to 40 AU, with data rate requirements in the 1's to 1000's of Mbits/second. The near term demand is driven by NASA's Space Science Enterprise which wishes to deploy more capable instruments onboard spacecraft and increase the number of deep space missions. The long term demand is driven by missions with extreme communications challenges such as very high data rates from the outer planets, supporting sub-surface exploration, or supporting NASA's Human Exploration and Development of Space Enterprise beyond Earth orbit. Laser communications is a revolutionary communications technology that will dramatically increase NASA's ability to transmit information across the solar system. Lasercom sends information using beams of light and optical elements, such as telescopes and optical amplifiers, rather than RF signals, amplifiers, and antennas. This paper provides an overview of different network options at Earth to meet NASA's deep space lasercom requirements. It is based mainly on work done for the Mars Laser Communications Demonstration Project, a joint project between NASA's Goddard Space Flight Center (GSFC), the Jet Propulsion Laboratory, California Institute of Technology (JPL), and the Massachusetts Institute of Technology Lincoln Laboratory (MIT/LL). It reports preliminary conclusions from the Mars Lasercom Study conducted at MIT/LL and on additional work done for the Tracking and Data Relay Satellite System Continuation Study at GSFC. A lasercom flight terminal will be flown on the Mars Telesat Orbiter (MTO) to be launched by NASA in 2009, and will be the first high rate deep space demonstration of this revolutionary technology.

First Experimental Demonstration of Full-Duplex Optical Communication on a Single Beam

NASA Technical Reports Server (NTRS)

Garrett, Christopher David; Shay, Thomas

2001-01-01

The satellite industry is driven by the need to reduce costs. One way they have sought to do this is by reducing the size and weight of the satellite because of the extremely high cost per kilogram incurred launching a payload into orbit. The main difficulty in this approach is the lack of power capacity in a small satellite. One of the largest loads on a satellite's power system is the communications system. This has driven the need for a low-power communications system. This document examines a novel method of communicating optically with a low-Earth-orbit satellite from the ground without the need for a laser on the payload. The goal is to show the feasibility of such a system as a solution to the small satellite low-powered communication problem. Specially, that the system described herein: is capable of ground to low-Earth-orbit communications, has very little space-borne mass, and draws little power from the satellite. First, the system (hereafter referred to as LOWCAL "Lightweight Optical Wavelength Communication without A Laser in space") will be explained with details of the formats used and the link budgets. Discussions will be presented on the development of some of the system hardware (the laser diode driver, liquid crystal driver, and decision electronics for both the up and down links.) Finally, experimental test results of the entire system operating in a laboratory environment are presented and compared to theory. The results of the laboratory experiment support the original thesis: retro-modulated optical communications can meet the needs of the small satellite community. The system is capable of 10-kbps communication, has low space-borne mass, and draws little power from the satellite (less than 100-mW measured for the laboratory experiment, less than 1.5-W calculated for the Shuttle experiment).

Remotely Powered Reconfigurable Receiver for Extreme Sensing Platforms

NASA Technical Reports Server (NTRS)

Sheldon, Douglas J. (Inventor)

2017-01-01

Unmanned space programs are currently used to enable scientists to explore and research the furthest reaches of outer space. Systems and methods for low power communication devices in accordance with embodiments of the invention are disclosed, describing a wide variety of low power communication devices capable of remotely collecting, processing, and transmitting data from outer space in order to further mankind's goal of exploring the cosmos. Many embodiments of the invention include a Flash-based FPGA, an energy-harvesting power supply module, a sensor module, and a radio module. By utilizing technologies that withstand the harsh environment of outer space, more reliable low power communication devices can be deployed, enhancing the quality and longevity of the low power communication devices, enabling more data to be gathered and aiding in the exploration of outer space.

Organizational Metamorphosis in Space Research and Development.

ERIC Educational Resources Information Center

Tompkins, Phillip K.

1978-01-01

The communicative, and therefore organizational and managerial, aspects of the Marshall Space Flight Center's (MSFC) metamorphosis from Saturn V to Skylab are analyzed. MSFC's consistent successes are attributed to the organization's commitment to communication systems, its technical integrity, and its single-minded purpose. (JMF)

Space Telecommunications Radio System (STRS) Architecture. Part 1; Tutorial - Overview

NASA Technical Reports Server (NTRS)

Handler, Louis M.; Briones, Janette C.; Mortensen, Dale J.; Reinhart, Richard C.

2012-01-01

Space Telecommunications Radio System (STRS) Architecture Standard provides a NASA standard for software-defined radio. STRS is being demonstrated in the Space Communications and Navigation (SCaN) Testbed formerly known as Communications, Navigation and Networking Configurable Testbed (CoNNeCT). Ground station radios communicating the SCaN testbed are also being written to comply with the STRS architecture. The STRS Architecture Tutorial Overview presents a general introduction to the STRS architecture standard developed at the NASA Glenn Research Center (GRC), addresses frequently asked questions, and clarifies methods of implementing the standard. The STRS architecture should be used as a base for many of NASA s future telecommunications technologies. The presentation will provide a basic understanding of STRS.

Space Based Communications

NASA Technical Reports Server (NTRS)

Simpson, James; Denson, Erik; Valencia, Lisa; Birr, Richard

2003-01-01

Current space lift launches on the Eastern and Western Range require extensive ground-based real-time tracking, communications and command/control systems. These are expensive to maintain and operate and cover only limited geographical areas. Future spaceports will require new technologies to provide greater launch and landing opportunities, support simultaneous missions, and offer enhanced decision support models and simulation capabilities. These ranges must also have lower costs and reduced complexity while continuing to provide unsurpassed safety to the public, flight crew, personnel, vehicles and facilities. Commercial and government space-based assets for tracking and communications offer many attractive possibilities to help achieve these goals. This paper describes two NASA proof-of-concept projects that seek-to exploit the advantages of a space-based range: Iridium Flight Modem and Space-Based Telemetry and Range Safety (STARS). Iridium Flight Modem uses the commercial satellite system Iridium for extremely low cost, low rate two-way communications and has been successfully tested on four aircraft flights. A sister project at Goddard Space Flight Center's (GSFC) Wallops Flight Facility (WFF) using the Globalstar system has been tested on one rocket. The basic Iridium Flight Modem system consists of a L1 carrier Coarse/Acquisition (C/A)-Code Global Positioning System (GPS) receiver, an on-board computer, and a standard commercial satellite modem and antennas. STARS uses the much higher data rate NASA owned Tracking and Data Relay Satellite System (TDRSS), a C/A-Code GPS receiver, an experimental low-power transceiver, custom built command and data handler processor, and digitized flight termination system (FTS) commands. STARS is scheduled to fly on an F-15 at Dryden Flight Research Center in the spring of 2003, with follow-on tests over the next several years.

Developing a Standard Method for Link-Layer Security of CCSDS Space Communications

NASA Technical Reports Server (NTRS)

Biggerstaff, Craig

2009-01-01

Communications security for space systems has been a specialized field generally far removed from considerations of mission interoperability and cross-support in fact, these considerations often have been viewed as intrinsically opposed to security objectives. The space communications protocols defined by the Consultative Committee for Space Data Systems (CCSDS) have a twenty-five year history of successful use in over 400 missions. While the CCSDS Telemetry, Telecommand, and Advancing Orbiting Systems protocols for use at OSI Layer 2 are operationally mature, there has been no direct support within these protocols for communications security techniques. Link-layer communications security has been successfully implemented in the past using mission-unique methods, but never before with an objective of facilitating cross-support and interoperability. This paper discusses the design of a standard method for cryptographic authentication, encryption, and replay protection at the data link layer that can be integrated into existing CCSDS protocols without disruption to legacy communications services. Integrating cryptographic operations into existing data structures and processing sequences requires a careful assessment of the potential impediments within spacecraft, ground stations, and operations centers. The objective of this work is to provide a sound method for cryptographic encapsulation of frame data that also facilitates Layer 2 virtual channel switching, such that a mission may procure data transport services as needed without involving third parties in the cryptographic processing, or split independent data streams for separate cryptographic processing.

EASCON '88; Proceedings of the Twenty-first Annual Electronics and Aerospace Conference, Arlington, VA, Nov. 9-11, 1988

NASA Astrophysics Data System (ADS)

The capabilities of present and future space and terrestrial communication systems are examined in reviews and reports. Topics addressed include competition between space and terrestrial technologies, remote sensing, carrier services in public switched telephone networks, surveillance and warning systems, telescience and telerobotics, integrated networks and systems, and military communication systems. Consideration is given to navigation and geolocation services; high-definition TV broadcasting; technical, economic, marketing, and strategic aspects of VSATs; future technology drivers; and SDI technologies.

Large space antenna communications systems: Integrated Langley Research Center/Jet Propulsion Laboratory technology development activities. 1: Introduction

NASA Technical Reports Server (NTRS)

Campbell, T. G.

1983-01-01

The Jet Propulsion Laboratory and the Langley Research Center have been developing technology related to large space antennas (LSA) during the past several years. The need for a communication system research program became apparent during the recent studies for the Land Mobile Satellite System. This study indicated the need for additional research in (1) electromagnetic analysis methods, (2) design and development of multiple beam feed systems, and (3) the measurement methods for LSA reflectors.

Polyhedral integrated and free space optical interconnection

DOEpatents

Erteza, I.A.

1998-01-06

An optical communication system uses holographic optical elements to provide guided wave and non-guided communication, resulting in high bandwidth, high connectivity optical communications. Holograms within holographic optical elements route optical signals between elements and between nodes connected to elements. Angular and wavelength multiplexing allow the elements to provide high connectivity. The combination of guided and non-guided communication allows compact polyhedral system geometries. Guided wave communications provided by multiplexed substrate-mode holographic optical elements eases system alignment. 7 figs.

Polyhedral integrated and free space optical interconnection

DOEpatents

Erteza, Ireena A.

1998-01-01

An optical communication system uses holographic optical elements to provide guided wave and non-guided communication, resulting in high bandwidth, high connectivity optical communications. Holograms within holographic optical elements route optical signals between elements and between nodes connected to elements. Angular and wavelength multiplexing allow the elements to provide high connectivity. The combination of guided and non-guided communication allows compact polyhedral system geometries. Guided wave communications provided by multiplexed substrate-mode holographic optical elements eases system alignment.

Task six report: Spacecraft communication terminal evaluation. [analysis of space communication at six different wavelengths in radio and optical frequency regions

NASA Technical Reports Server (NTRS)

1973-01-01

An analytical comparison is made of space communication accomplished at six different wavelengths. In the radio band, 2.25, 7.5, and 14.5 GHz systems are analyzed, while at optical wavelengths, 0.53, 1.06 and 10.6 micron systems are examined. The purpose of the comparison is to determine which of these systems will require the least hardware weight to perform a given communication task. The problem is solved by requiring each communication system to meet a given performance while selecting combinations of transmitted power and antenna diameter to obtain the least overall system weight. This performance is provided while maintaining practical values for parameters other than antenna diameter and power, which also affect system performance. The results of the analysis indicate that for future data links over ranges of 42,000 to 84,000 km and with data bandwidths of 100 to 1000 MHz, the CO2 laser system will provide the required performance with the least total system weight impact on a spacecraft.

The role of space communication in promoting national development with specific reference to experiments conducted in India

NASA Astrophysics Data System (ADS)

Chitnis, E. V.

The paper describes the role of space communication in promoting national development with special reference to experiments conducted in India, namely SITE (1975-1976), STEP (1977-1979) and APPLE (1981 onwards). The impact of these experiments in economic, cultural and educational terms are discussed, pointing out social implications involved in using advance space communication technology for instruction and information in the areas of education, national integration and development. The paper covers special requirements which arise when a communication system covers backward and remote rural areas in a developing country. The impact on the population measured by conducting social surveys has been discussed - especially the gains of predominently illiterate new media - participants have been highlighted. Possibilities of improving skills of teachers, the quality of the primary and higher education have been covered. The preparation required both on ground as well as space to derive benefits of space technology are considered. A profile of INSAT which marks the culmination of the experimental phase and the beginning of operational domestic satellite system is sketched.

Demonstration of Space Optical Transmitter Development for Multiple High Frequency Bands

NASA Technical Reports Server (NTRS)

Nguyen, Hung; Simons, Rainee; Wintucky, Edwin; Freeman, Jon

2013-01-01

As the demand for multiple radio frequency carrier bands continues to grow in space communication systems, the design of a cost-effective compact optical transmitter that is capable of transmitting selective multiple RF bands is of great interest, particularly for NASA Space Communications Network Programs. This paper presents experimental results that demonstrate the feasibility of a concept based on an optical wavelength division multiplexing (WDM) technique that enables multiple microwave bands with different modulation formats and bandwidths to be combined and transmitted all in one unit, resulting in many benefits to space communication systems including reduced size, weight and complexity with corresponding savings in cost. Experimental results will be presented including the individual received RF signal power spectra for the L, C, X, Ku, Ka, and Q frequency bands, and measurements of the phase noise associated with each RF frequency. Also to be presented is a swept RF frequency power spectrum showing simultaneous multiple RF frequency bands transmission. The RF frequency bands in this experiment are among those most commonly used in NASA space environment communications.

NASA Near Earth Network (NEN), Deep Space Network (DSN) and Space Network (SN) Support of CubeSat Communications

NASA Technical Reports Server (NTRS)

Schaire, Scott H.; Altunc, Serhat; Bussey, George; Shaw, Harry; Horne, Bill; Schier, Jim

2015-01-01

There has been a historical trend to increase capability and drive down the Size, Weight and Power (SWAP) of satellites and that trend continues today. Small satellites, including systems conforming to the CubeSat specification, because of their low launch and development costs, are enabling new concepts and capabilities for science investigations across multiple fields of interest to NASA. NASA scientists and engineers across many of NASAs Mission Directorates and Centers are developing exciting CubeSat concepts and welcome potential partnerships for CubeSat endeavors. From a communications and tracking point of view, small satellites including CubeSats are a challenge to coordinate because of existing small spacecraft constraints, such as limited SWAP and attitude control, low power, and the potential for high numbers of operational spacecraft. The NASA Space Communications and Navigation (SCaN) Programs Near Earth Network (NEN), Deep Space Network (DSN) and the Space Network (SN) are customer driven organizations that provide comprehensive communications services for space assets including data transport between a missions orbiting satellite and its Mission Operations Center (MOC). The NASA NEN consists of multiple ground antennas. The SN consists of a constellation of geosynchronous (Earth orbiting) relay satellites, named the Tracking and Data Relay Satellite System (TDRSS). The DSN currently makes available 13 antennas at its three tracking stations located around the world for interplanetary communication. The presentation will analyze how well these space communication networks are positioned to support the emerging small satellite and CubeSat market. Recognizing the potential support, the presentation will review the basic capabilities of the NEN, DSN and SN in the context of small satellites and will present information about NEN, DSN and SN-compatible flight radios and antenna development activities at the Goddard Space Flight Center (GSFC) and across industry. The presentation will review concepts on how the SN multiple access capability could help locate CubeSats and provide a low-latency early warning system. The presentation will also present how the DSN is evolving to maximize use of its assets for interplanetary CubeSats. The critical spectrum-related topics of available and appropriate frequency bands, licensing, and coordination will be reviewed. Other key considerations, such as standardization of radio frequency interfaces and flight and ground communications hardware systems, will be addressed as such standardization may reduce the amount of time and cost required to obtain frequency authorization and perform compatibility and end-to-end testing. Examples of standardization that exist today are the NASA NEN, DSN and SN systems which have published users guides and defined frequency bands for high data rate communication, as well as conformance to CCSDS standards. The workshop session will also seek input from the workshop participants to better understand the needs of small satellite systems and to identify key development activities and operational approaches necessary to enhance communication and navigation support using NASA's NEN, DSN and SN.

BER Analysis of Coherent Free-Space Optical Communication Systems with a Focal-Plane-Based Wavefront Sensor

NASA Astrophysics Data System (ADS)

Cao, Jingtai; Zhao, Xiaohui; Liu, Wei; Gu, Haijun

2018-03-01

A wavefront sensor is one of most important units for an adaptive optics system. Based on our previous works, in this paper, we discuss the bit-error-rate (BER) performance of coherent free space optical communication systems with a focal-plane-based wavefront sensor. Firstly, the theory of a focal-plane-based wavefront sensor is given. Then the relationship between the BER and the mixing efficiency with a homodyne receiver is discussed on the basis of binary-phase-shift-keying (BPSK) modulation. Finally, the numerical simulation results are shown that the BER will be decreased obviously after aberrations correction with the focal-plane-based wavefront sensor. In addition, the BER will decrease along with increasing number of photons received within a single bit. These analysis results will provide a reference for the design of the coherent Free space optical communication (FSOC) system.

Swanson uses communication equipment in the A/L during Joint Operations

NASA Image and Video Library

2007-06-12

S117-E-07099 (12 June 2007) --- Astronaut Steven Swanson, STS-117 mission specialist, uses a communication system in the Quest Airlock of the International Space Station during flight day five activities while Space Shuttle Atlantis was docked with the station.

Interface Circuit Board For Space-Shuttle Communications

NASA Technical Reports Server (NTRS)

Parrish, Brett T.

1995-01-01

Report describes interface electronic circuit developed to enable ground controllers to send commands and data via Ku-band radio uplink to multiple circuits connected to standard IEEE-488 general-purpose interface bus in space shuttle. Design of circuit extends data-throughput capability of communication system.

14 CFR 1310.7 - Communications with the Board.

Code of Federal Regulations, 2010 CFR

2010-01-01

... 14 Aeronautics and Space 5 2010-01-01 2010-01-01 false Communications with the Board. 1310.7 Section 1310.7 Aeronautics and Space AIR TRANSPORTATION SYSTEM STABILIZATION AIR TRANSPORTATION STABILIZATION BOARD AIR CARRIER GUARANTEE LOAN PROGRAM ADMINISTRATIVE REGULATIONS AND AMENDMENT OR WAIVER OF A...

A Wideband Autonomous Cognitive Radio Development and Prototyping System

DTIC Science & Technology

2017-11-14

Gain, High Frequency , Circularly Polarized Planar Antenna Arrays for Space Applications”, NASA. 3. C. G. Christodoulou (Co-Principal Investigator...Investigator), “Cognitive Communications for SATCOM”, Space Vehicles (RV) University Grants Program, 04/26/16-04/25/17 ($150K), Air Force Research...Aerospace (Prime Contractor). 2. S. K. Jayaweera (Principal Investigator), “Cognitive Communications for SATCOM”, Space Vehicles (RV) University Grants

NASA's First Laser Communication System

NASA Image and Video Library

2017-12-08

A new NASA-developed, laser-based space communication system will enable higher rates of satellite communications similar in capability to high-speed fiber optic networks on Earth. The space terminal for the Lunar Laser Communication Demonstration (LLCD), NASA's first high-data-rate laser communication system, was recently integrated onto the Lunar Atmosphere and Dust Environment Explorer (LADEE) spacecraft. LLCD will demonstrate laser communications from lunar orbit to Earth at six times the rate of the best modern-day advanced radio communication systems. Credit: NASA ----- What is LADEE? The Lunar Atmosphere and Dust Environment Explorer (LADEE) is designed to study the Moon's thin exosphere and the lunar dust environment. An "exosphere" is an atmosphere that is so thin and tenuous that molecules don't collide with each other. Studying the Moon's exosphere will help scientists understand other planetary bodies with exospheres too, like Mercury and some of Jupiter's bigger moons. The orbiter will determine the density, composition and temporal and spatial variability of the Moon's exosphere to help us understand where the species in the exosphere come from and the role of the solar wind, lunar surface and interior, and meteoric infall as sources. The mission will also examine the density and temporal and spatial variability of dust particles that may get lofted into the atmosphere. The mission also will test several new technologies, including a modular spacecraft bus that may reduce the cost of future deep space missions and demonstrate two-way high rate laser communication for the first time from the Moon. LADEE now is ready to launch when the window opens on Sept. 6, 2013. Read more: www.nasa.gov/ladee NASA image use policy. NASA Goddard Space Flight Center enables NASA’s mission through four scientific endeavors: Earth Science, Heliophysics, Solar System Exploration, and Astrophysics. Goddard plays a leading role in NASA’s accomplishments by contributing compelling scientific knowledge to advance the Agency’s mission. Follow us on Twitter Like us on Facebook Find us on Instagram

Practical Applications of Space Systems, Supporting Paper 2: Uses of Communications.

ERIC Educational Resources Information Center

National Academy of Sciences - National Research Council, Washington, DC. Assembly of Engineering.

This report summarizes the findings of one of fourteen panels that studied progress in space science applications and defined user needs potentially capable of being met by space-system applications. The study was requested by the National Aeronautics and Space Administration (NASA) and was conducted by the Space Applications Board. The panels…

Implementation and Testing of the JANUS Standard with SSC Pacific’s Software-Defined Acoustic Modem

DTIC Science & Technology

2017-12-01

Communications Outpost (FDECO) Innovative Naval Prototype (INP) Program by the Advanced Photonic Technologies Branch (Code 55360), Space and Naval Warfare... Communications and Networks Division iii EXECUTIVE SUMMARY This report presents Space and Naval Warfare (SPAWAR) Systems Center Pacific’s (SSC... Frequency -Hopped Binary Frequency Shift Keying Office of Naval Research Innovative Naval Prototype Forward Deployed Energy and Communications Outpost

Free Space Laser Communications

NASA Technical Reports Server (NTRS)

Lesh, James

2000-01-01

This presentation concerns the use of Laser communication for deep space applications. The presentation reviews the problems with electromagnetic beams and then the advantages and disadvantages of the use of optical communication. The presentation then reviews some of the spacecraft technology with pictures of some of the devices. The ground reception systems and the simplified link calculation are also reviewed. Recent and planned demonstration projects are also reviewed.

Fundamentals of Free-Space Optical Communications

NASA Technical Reports Server (NTRS)

Dolinar, Sam; Moision, Bruce; Erkmen, Baris

2012-01-01

Free-space optical communication systems potentially gain many dBs over RF systems. There is no upper limit on the theoretically achievable photon efficiency when the system is quantum-noise-limited: a) Intensity modulations plus photon counting can achieve arbitrarily high photon efficiency, but with sub-optimal spectral efficiency. b) Quantum-ideal number states can achieve the ultimate capacity in the limit of perfect transmissivity. Appropriate error correction codes are needed to communicate reliably near the capacity limits. Poisson-modeled noises, detector losses, and atmospheric effects must all be accounted for: a) Theoretical models are used to analyze performance degradations. b) Mitigation strategies derived from this analysis are applied to minimize these degradations.

Applications of CCSDS recommendations to Integrated Ground Data Systems (IGDS)

NASA Technical Reports Server (NTRS)

Mizuta, Hiroshi; Martin, Daniel; Kato, Hatsuhiko; Ihara, Hirokazu

1993-01-01

This paper describes an application of the CCSDS Principle Network (CPH) service model to communications network elements of a postulated Integrated Ground Data System (IGDS). Functions are drawn principally from COSMICS (Cosmic Information and Control System), an integrated space control infrastructure, and the Earth Observing System Data and Information System (EOSDIS) Core System (ECS). From functional requirements, this paper derives a set of five communications network partitions which, taken together, support proposed space control infrastructures and data distribution systems. Our functional analysis indicates that the five network partitions derived in this paper should effectively interconnect the users, centers, processors, and other architectural elements of an IGDS. This paper illustrates a useful application of the CCSDS (Consultive Committee for Space Data Systems) Recommendations to ground data system development.

Space Station needs, attributes and architectural options study. Volume 7-4A: Data book, architecture, technology and programmatics, part A

NASA Technical Reports Server (NTRS)

1983-01-01

Various parameters of the orbital space station are discussed. The space station environment, data management system, communication and tracking, environmental control, and life support system are considered. Specific topics reviewed include crew work stations, restraint systems, stowage, computer hardware, and expert systems.

Early Communication System (ECOMM) for ISS

NASA Technical Reports Server (NTRS)

Gaylor, Kent; Tu, Kwei

1999-01-01

The International Space Station (ISS) Early Communications System (ECOMM) was a Johnson Space Center (JSC) Avionic Systems Division (ASD) in-house developed communication system to provide early communications between the ISS and the Mission Control Center-Houston (MCC-H). This system allows for low rate commands (link rate of 6 kbps) to be transmitted through the Tracking and Data Relay Satellite System (TDRSS) from MCC-H to the ISS using TDRSS's S-band Single Access Forward (SSA/) link service. This system also allows for low rate telemetry (link rate of 20.48 kbps) to be transmitted from ISS to MCC-H through the TDRSS using TDRSS's S-band Single Access Return (SSAR) link service. In addition this system supports a JSC developed Onboard Communications Adapter (OCA) that allows for a two-way data exchange of 128 kbps between MCC-H and the ISS through TDRSS. This OCA data can be digital video/audio (two-way videoconference), and/or file transfers, and/or "white board". The key components of the system, the data formats used by the system to insure compatibility with the future ISS S-Band System, as well as how other vehicles may be able to use this system for their needs are discussed in this paper.

Design of stabilized platforms for deep space optical communications (DSOC)

NASA Astrophysics Data System (ADS)

Jacka, N.; Walter, R.; Laughlin, D.; McNally, J.

2017-02-01

Numerous Deep Space Optical Communications (DSOC) demonstrations are planned by NASA to provide the basis for future implementation of optical communications links in planetary science missions and eventually manned missions to Mars. There is a need for a simple, robust precision optical stabilization concept for long-range free space optical communications applications suitable for optical apertures and masses larger than the current state of the art. We developed a stabilization concept by exploiting the ultra-low noise and wide bandwidth of ATA-proprietary Magnetohydrodynamic (MHD) angular rate sensors and building on prior practices of flexure-based isolation. We detail a stabilization approach tailored for deep space optical communications, and present an innovative prototype design and test results. Our prototype system provides sub-micro radian stabilization for a deep space optical link such as NASA's integrated Radio frequency and Optical Communications (iROC) and NASA's DSOC programs. Initial test results and simulations suggest that >40 dB broadband jitter rejection is possible without placing unrealistic expectations on the control loop bandwidth and flexure isolation frequency. This approach offers a simple, robust method for platform stabilization without requiring a gravity offload apparatus for ground testing or launch locks to survive a typical launch environment. This paper reviews alternative stabilization concepts, their advantages and disadvantages, as well as, their applicability to various optical communications applications. We present results from testing that subjected the prototype system to realistic spacecraft base motion and confirmed predicted sub-micro radian stabilization performance with a realistic 20-cm aperture.

Enhancing performance of next generation FSO communication systems using soft computing-based predictions.

PubMed

Kazaura, Kamugisha; Omae, Kazunori; Suzuki, Toshiji; Matsumoto, Mitsuji; Mutafungwa, Edward; Korhonen, Timo O; Murakami, Tadaaki; Takahashi, Koichi; Matsumoto, Hideki; Wakamori, Kazuhiko; Arimoto, Yoshinori

2006-06-12

The deterioration and deformation of a free-space optical beam wave-front as it propagates through the atmosphere can reduce the link availability and may introduce burst errors thus degrading the performance of the system. We investigate the suitability of utilizing soft-computing (SC) based tools for improving performance of free-space optical (FSO) communications systems. The SC based tools are used for the prediction of key parameters of a FSO communications system. Measured data collected from an experimental FSO communication system is used as training and testing data for a proposed multi-layer neural network predictor (MNNP) used to predict future parameter values. The predicted parameters are essential for reducing transmission errors by improving the antenna's accuracy of tracking data beams. This is particularly essential for periods considered to be of strong atmospheric turbulence. The parameter values predicted using the proposed tool show acceptable conformity with original measurements.

Non-Mechanical Beam Steering in Free-Space Optical Communication Transceivers

NASA Astrophysics Data System (ADS)

Shortt, Kevin

Free-space optical communications systems are a rapidly growing field as they carry many of the advantages of traditional fibre-based communications systems without the added investment of installing complex infrastructure. Moreover, these systems are finding key niches in mobile platforms in order to take advantage of the increased bandwidth over traditional RF systems. Of course, the inevitable problem of tracking arises when dealing with mobile stations. To compound the problem in the case of communications to low Earth or geosynchronous orbits, FSOC systems typically operate with tightly confined beams over great distances often requiring pointing accuracies on the order of micro-radians or smaller. Mechanisms such as gimbal mounts and fine-steering mirrors are the usual candidates for platform stabilization, however, these clearly have substantial power requirements and inflate the mass of the system. Spatial light modulators (also known as optical phased arrays), on the other hand, offer a suitable alternative for beam-pointing stabilization. Some of the advantages of spatial light modulators over fine-steering mirrors include programmable multiple simultaneous beams, dynamic focus/defocus and moderate to excellent optical power handling capability. This thesis serves as an investigation into the implementation of spatial light modulators as a replacement for traditional fine-steering mirrors in the fine-pointing subsystem. In particular, pointing accuracy and scanning ability will be highlighted as performance metrics in the context of a variety of communication scenarios. Keywords: Free-space optical communications, beam steering, fine-steering mirror, spatial light modulator, optical phased array.

Learning Affordances of Language and Communication National Curricula

ERIC Educational Resources Information Center

Scott, David

2016-01-01

This article focuses on the learning affordances of different language and communication curricula in the world. For reasons of space, only two national education systems (Finland and Singapore) and their language and communication curricula are referred to. The accounts of national education systems consist of the identification of mechanisms…

The Telecommunications and Data Acquisition

NASA Technical Reports Server (NTRS)

Posner, Edward C. (Editor)

1992-01-01

This quarterly publication provides archival reports on developments in programs managed by JPL's Office of Telecommunications and Data Acquisition (TDA). In space communications, radio navigation, radio science, and ground-based radio and radar astronomy, it reports on activities of the Deep Space Network (DSN) in planning, supporting research and technology, implementation, and operations. Also included are standards activity at JPL for space data and information systems and reimbursable DSN work performed for other space agencies through NASA. The preceding work is all performed for NASA's Office of Space Communications (OSC).

Wideband 1.064 micrometer detector evaluation. [for application to space laser communication systems

NASA Technical Reports Server (NTRS)

Green, S. I.

1977-01-01

Several types of communications detectors for use in a 400 Mbps 1.064 micrometer laser communication system were evaluated and characterized. The communication system Bit Error Rate (BER) performance was measured, and test results for the best detector of each type are summarized. The complete BER curves are presented. The 400 Mbps 1.064 micrometer communication system receiver test bed is described. The best performance levels which can be achieved by focusing the signal to diffraction limited spots on the photosensitive area are cited.

Collaboration support system for "Phobos-Soil" space mission.

NASA Astrophysics Data System (ADS)

Nazarov, V.; Nazirov, R.; Zakharov, A.

2009-04-01

Rapid development of communication facilities leads growth of interactions done via electronic means. However we can see some paradox in this segment in last times: Extending of communication facilities increases collaboration chaos. And it is very sensitive for space missions in general and scientific space mission particularly because effective decision of this task provides successful realization of the missions and promises increasing the ratio of functional characteristic and cost of mission at all. Resolving of this problem may be found by using respective modern technologies and methods which widely used in different branches and not in the space researches only. Such approaches as Social Networking, Web 2.0 and Enterprise 2.0 look most prospective in this context. The primary goal of the "Phobos-Soil" mission is an investigation of the Phobos which is the Martian moon and particularly its regolith, internal structure, peculiarities of the orbital and proper motion, as well as a number of different scientific measurements and experiments for investigation of the Martian environment. A lot of investigators involved in the mission. Effective collaboration system is key facility for information support of the mission therefore. Further to main goal: communication between users of the system, modern approaches allows using such capabilities as self-organizing community, user generated content, centralized and federative control of the system. Also it may have one unique possibility - knowledge management which is very important for space mission realization. Therefore collaboration support system for "Phobos-Soil" mission designed on the base of multilayer model which includes such levels as Communications, Announcement and Information, Data sharing and Knowledge management. The collaboration support system for "Phobos-Soil" mission will be used as prototype for prospective Russian scientific space missions and the presentation describes its architecture, methodological and technical aspects of its design.

AFFECTS - Advanced Forecast For Ensuring Communications Through Space

NASA Astrophysics Data System (ADS)

Bothmer, Volker

2013-04-01

Through the AFFECTS project funded by the European Union's 7th Framework Programme, European and US scientists develop an advanced proto-type space weather warning system to safeguard the operation of telecommunication and navigation systems on Earth to the threat of solar storms. The project is led by the University of Göttingen's Institute for Astrophysics and comprises worldwide leading research and academic institutions and industrial enterprises from Germany, Belgium, Ukraine, Norway and the United States. The key objectives of the AFFECTS project are: State-of-the-art analysis and modelling of the Sun-Earth chain of effects on the Earth's ionosphere and their subsequent impacts on communication systems based on multipoint space observations and complementary ground-based data. Development of a prototype space weather early warning system and reliable space weather forecasts, with specific emphasis on ionospheric applications. Dissemination of new space weather products and services to end users, the scientific community and general public. The presentation summarizes the project highlights, with special emphasis on the developed space weather forecast tools.

The Telecommunications and Data Acquisition Report

NASA Technical Reports Server (NTRS)

Posner, Edward C. (Editor)

1993-01-01

This quarterly publication provides archival reports on developments in programs managed by JPL's Office of Telecommunications and Data Acquisition (TDA) in the following areas: space communications, radio navigation, radio science, and ground-based radio and radar astronomy. This document also reports on the activities of the Deep Space Network (DSN) in planning, supporting research and technology, implementation, and operations. Also included are standards activity at JPL for space data and information systems and reimbursable DSN work performed for other space agencies through NASA. The preceding work is all performed for NASA's Office of Space Communications (OSC). The TDA Office also performs work funded by another NASA program office through and with the cooperation of OSC. This is the Orbital Debris Radar Program with the Office of Space Systems Development.

Olivas uses communication equipment on the FD during Joint Operations

NASA Image and Video Library

2007-06-13

S117-E-07194 (13 June 2007) --- Astronaut John "Danny" Olivas, STS-117 mission specialist, uses a communication system while looking over procedures checklists on the flight deck of Space Shuttle Atlantis during flight day six activities while docked with the International Space Station.

Olivas uses communication equipment on the FD during Joint Operations

NASA Image and Video Library

2007-06-13

S117-E-07192 (13 June 2007) --- Astronaut John "Danny" Olivas, STS-117 mission specialist, uses a communication system while looking over procedures checklists on the flight deck of Space Shuttle Atlantis during flight day six activities while docked with the International Space Station.

Williams uses communication equipment in the Airlock during Expedition 13

NASA Image and Video Library

2006-05-01

ISS013-E-13327 (1 May 2006) --- Astronaut Jeffrey N. Williams, Expedition 13 NASA space station science officer and flight engineer, uses a communication system in the Quest Airlock of the International Space Station. Two Extravehicular Mobility Unit (EMU) spacesuits are visible in the background.

Free-space to few-mode-fiber coupling under atmospheric turbulence.

PubMed

Zheng, Donghao; Li, Yan; Chen, Erhu; Li, Beibei; Kong, Deming; Li, Wei; Wu, Jian

2016-08-08

High speed free space optical communication (FSOC) has taken advantages of components developed for fiber-optic communication systems. Recently, with the rapid development of few-mode-fiber based fiber communication systems, few-mode-fiber components might further promote their applications in FSOC system. The coupling efficiency between free space optical beam and few-mode fibers under atmospheric turbulence effect are investigated in this paper. Both simulation and experimental results show that, compared with single-mode fiber, the coupling efficiencies for a 2-mode fiber and a 4-mode fiber are improved by ~4 dB and ~7 dB respectively in the presence of medium moderate and strong turbulence. Compared with single-mode fiber, the relative standard deviation of received power is restrained by 51% and 66% respectively with a 4-mode and 2-mode fiber.

TYCHO: Demonstrator and operational satellite mission to Earth-Moon-Libration point EML-4 for communication relay provision as a service

NASA Astrophysics Data System (ADS)

Hornig, Andreas; Homeister, Maren

2015-03-01

In the current wake of mission plans to the Moon and to Earth-Moon Libration points (EML) by several agencies and organizations, TYCHO identifies the key role of telecommunication provision for the future path of lunar exploration. It demonstrates an interesting extension to existing communication methods to the Moon and beyond by combining innovative technology with a next frontier location and the commercial space communication sector. It is evident that all communication systems will rely on direct communication to Earth ground stations. In case of EML-2 missions around HALO orbits or bases on the far side of the Moon, it has to be extended by communication links via relay stations. The innovative approach is that TYCHO provides this relay communication to those out-of-sight lunar missions as a service. TYCHO will establish a new infrastructure for future missions and even create a new market for add-on relay services. The TMA-0 satellite is TYCHO's first phase and a proposed demonstrator mission to the Earth-Moon Libration point EML-4. It demonstrates relay services needed for automated exploratory and manned missions (Moon bases) on the rim (>90°E and >90°W) and far side surface, to lunar orbits and even to EML-2 halo orbits (satellites and space stations). Its main advantage is the permanent availability of communication coverage. This will provide full access to scientific and telemetry data and furthermore to crucial medical monitoring and safety. The communication subsystem is a platform for conventional communication but also a test-bed for optical communication with high data-rate LASER links to serve the future needs of manned bases and periodic burst data-transfer from lunar poles. The operational TMA-1 satellite is a stand-alone mission integrated into existing space communication networks to provide open communication service to external lunar missions. Therefore the long-time stable libration points EML-4 and -5 are selected to guarantee an operation time of up to 10 years. It also enables measurements of the libration point environment with the scientific payloads. This includes sensors for space dust, solar and cosmic radiation activity for satellite lifetime estimation and lunar crew protection by providing early-warning systems. The paper describes the mission concept and the pre-design of the demonstrator satellite according to the operational mission requirements, advantages and benefits of this service. The concept was awarded with the Space Generation Advisory Council and OHB Scholarship in 2011 and the concept study is conducted at the Institute of Space Systems (IRS) [1] of the University of Stuttgart and OHB-System, Bremen [2].

The Center for Space Telemetering and Telecommunications Systems

NASA Technical Reports Server (NTRS)

Horan, S.; DeLeon, P.; Borah, D.; Lyman, R.

2003-01-01

This report comprises the final technical report for the research grant 'Center for Space Telemetering and Telecommunications Systems' sponsored by the National Aeronautics and Space Administration's Goddard Space Flight Center. The grant activities are broken down into the following technology areas: (1) Space Protocol Testing; (2) Autonomous Reconfiguration of Ground Station Receivers; (3) Satellite Cluster Communications; and (4) Bandwidth Efficient Modulation. The grant activity produced a number of technical reports and papers that were communicated to NASA as they were generated. This final report contains the final summary papers or final technical report conclusions for each of the project areas. Additionally, the grant supported students who made progress towards their degrees while working on the research.

An Optimum Space-to-Ground Communication Concept for CubeSat Platform Utilizing NASA Space Network and Near Earth Network

NASA Technical Reports Server (NTRS)

Wong, Yen F.; Kegege, Obadiah; Schaire, Scott H.; Bussey, George; Altunc, Serhat; Zhang, Yuwen; Patel, Chitra

2016-01-01

National Aeronautics and Space Administration (NASA) CubeSat missions are expected to grow rapidly in the next decade. Higher data rate CubeSats are transitioning away from Amateur Radio bands to higher frequency bands. A high-level communication architecture for future space-to-ground CubeSat communication was proposed within NASA Goddard Space Flight Center. This architecture addresses CubeSat direct-to-ground communication, CubeSat to Tracking Data Relay Satellite System (TDRSS) communication, CubeSat constellation with Mothership direct-to-ground communication, and CubeSat Constellation with Mothership communication through K-Band Single Access (KSA).A Study has been performed to explore this communication architecture, through simulations, analyses, and identifying technologies, to develop the optimum communication concepts for CubeSat communications. This paper will present details of the simulation and analysis that include CubeSat swarm, daughter shipmother ship constellation, Near Earth Network (NEN) S and X-band direct to ground link, TDRS Multiple Access (MA) array vs Single Access mode, notional transceiverantenna configurations, ground asset configurations and Code Division Multiple Access (CDMA) signal trades for daughter mother CubeSat constellation inter-satellite crosslink. Results of Space Science X-band 10 MHz maximum achievable data rate study will be summarized. Assessment of Technology Readiness Level (TRL) of current CubeSat communication technologies capabilities will be presented. Compatibility test of the CubeSat transceiver through NEN and Space Network (SN) will be discussed. Based on the analyses, signal trade studies and technology assessments, the functional design and performance requirements as well as operation concepts for future CubeSat end-to-end communications will be derived.

Lunar Communication Terminals for NASA Exploration Missions: Needs, Operations Concepts and Architectures

NASA Technical Reports Server (NTRS)

Bhasin, Kul B.; Warner, Joseph D.; Anderson, Lynn M.

2008-01-01

NASA is conducting architecture studies prior to deploying a series of short- and long-duration human and robotic missions for the exploration of the Moon and Mars under the Vision for Space Exploration Initiative. A key objective of these missions is to establish and expand, through a series of launches, a system of systems approach to exploration capabilities and science return. The systems identified were Crew Exploration Vehicles, crew and cargo launch vehicles, crew EVA suits, crew and cargo landers, habitats, mobility carriers, and small, pressurized rovers. Multiple space communication networks and systems, deployed over time, will support these space exploration systems of systems. Each deployment phase will support interoperability of components and provide 20 years of legacy systems. In this paper, we describe the modular lunar communications terminals needed for the emerging lunar mission operational scenarios. These lunar communication terminals require flexibility for use in stationary, integrated, and mobile environments. They will support links directly to Earth, to lunar relay satellites, to astronauts and to fixed and mobile lunar surface systems. The operating concepts and traffic models are presented for these terminals within variety of lunar scenarios. A preliminary architecture is outlined, providing for suitable long-duration operations in the harsh lunar environment.

Ergodic channel capacity of spatial correlated multiple-input multiple-output free space optical links using multipulse pulse-position modulation

NASA Astrophysics Data System (ADS)

Wang, Huiqin; Wang, Xue; Cao, Minghua

2017-02-01

The spatial correlation extensively exists in the multiple-input multiple-output (MIMO) free space optical (FSO) communication systems due to the channel fading and the antenna space limitation. Wilkinson's method was utilized to investigate the impact of spatial correlation on the MIMO FSO communication system employing multipulse pulse-position modulation. Simulation results show that the existence of spatial correlation reduces the ergodic channel capacity, and the reception diversity is more competent to resist this kind of performance degradation.

Apollo experience report: Lunar module communications system

NASA Technical Reports Server (NTRS)

Dietz, R. H.; Rhoades, D. E.; Davidson, L. J.

1972-01-01

The development of the lunar module communications system is traced from the initial concept to the operational system used on manned lunar missions. The problems encountered during the development, the corrective actions taken, and recommendations for similar equipment in future programs are included. The system was designed to provide communications between the lunar module and the manned space flight network, between the lunar module and the command and service module, and between the lunar module and the extravehicular crewmen. The system provided the equipment necessary for voice, telemetry, and television communications; ranging information; and various communications links.

Selection of a Data Acquisition and Controls System Communications and Software Architecture for Johnson Space Center's Space Environment Simulation Laboratory Thermal and Vacuum Test Facilities

NASA Technical Reports Server (NTRS)

Jordan, Eric A.

2004-01-01

Upgrade of data acquisition and controls systems software at Johnson Space Center's Space Environment Simulation Laboratory (SESL) involved the definition, evaluation and selection of a system communication architecture and software components. A brief discussion of the background of the SESL and its data acquisition and controls systems provides a context for discussion of the requirements for each selection. Further framework is provided as upgrades to these systems accomplished in the 1990s and in 2003 are compared to demonstrate the role that technological advances have had in their improvement. Both of the selections were similar in their three phases; 1) definition of requirements, 2) identification of candidate products and their evaluation and testing and 3) selection by comparison of requirement fulfillment. The candidates for the communication architecture selection embraced several different methodologies which are explained and contrasted. Requirements for this selection are presented and the selection process is described. Several candidates for the software component of the data acquisition and controls system are identified, requirements for evaluation and selection are presented, and the evaluation process is described.

Space Mobile Network: A Near Earth Communication and Navigation Architecture

NASA Technical Reports Server (NTRS)

Israel, Dave J.; Heckler, Greg; Menrad, Robert J.

2016-01-01

This paper describes a Space Mobile Network architecture, the result of a recently completed NASA study exploring architectural concepts to produce a vision for the future Near Earth communications and navigation systems. The Space Mobile Network (SMN) incorporates technologies, such as Disruption Tolerant Networking (DTN) and optical communications, and new operations concepts, such as User Initiated Services, to provide user services analogous to a terrestrial smartphone user. The paper will describe the SMN Architecture, envisioned future operations concepts, opportunities for industry and international collaboration and interoperability, and technology development areas and goals.

Sun-Burned: Space Weather’s Impact On U.S. National Security

DTIC Science & Technology

2013-06-01

for navigation, the wideband global satellite communications system used for secure links in multiple frequencies , the space-based infrared system...used for early warning missile detection, the advanced extremely high frequency used for jam resistant strategic communications , and the defense...NAME(S) AND ADDRESS(ES) 10. SPONSOR/MONITOR’S ACRONYM(S) 11 . SPONSOR/MONITOR’S REPORT NUMBER(S) 12. DISTRIBUTION/AVAILABILITY STATEMENT Approved for

Ivanishin wearing a communication system headset in the SM

NASA Image and Video Library

2012-01-05

ISS030-E-021036 (5 Jan. 2012) --- Russian cosmonaut Anatoly Ivanishin, Expedition 30 flight engineer, wears a communication system headset while using a computer in the Zvezda Service Module of the International Space Station.

14 CFR 1201.200 - General.

Code of Federal Regulations, 2013 CFR

2013-01-01

... development in astrophysics, life sciences, Earth sciences and applications, solar system exploration, space physics, communications, microgravity science and applications, and communications and information systems... computational and experimental fluid dynamics and aerodynamics; fluid and thermal physics; rotorcraft, powered...

14 CFR § 1201.200 - General.

Code of Federal Regulations, 2014 CFR

2014-01-01

... development in astrophysics, life sciences, Earth sciences and applications, solar system exploration, space physics, communications, microgravity science and applications, and communications and information systems... computational and experimental fluid dynamics and aerodynamics; fluid and thermal physics; rotorcraft, powered...

14 CFR 1201.200 - General.

Code of Federal Regulations, 2012 CFR

2012-01-01

... development in astrophysics, life sciences, Earth sciences and applications, solar system exploration, space physics, communications, microgravity science and applications, and communications and information systems... computational and experimental fluid dynamics and aerodynamics; fluid and thermal physics; rotorcraft, powered...

Wireless Communications

NASA Astrophysics Data System (ADS)

1991-01-01

A technology utilization project led to the commercial adaptation of a Space Shuttle Orbiter wireless infrared voice communications system. The technology was adapted to a LAN system by Wilton Industries, one of the participants. Because the system is cable-free, installation charges are saved, and it can be used where cable is impractical. Resultant products include the IRplex 6000. Transceivers can be located anywhere and can include mobile receivers. The system provides wireless LAN coverage up to 44,000 square feet. applications include stock exchange communications, trade shows, emergency communications, etc.

Ionosphere-related products for communication and navigation

NASA Astrophysics Data System (ADS)

Tobiska, W.; Schunk, R. W.; Sojka, J. J.; Carlson, H. C.; Gardner, L. C.; Scherliess, L.; Zhu, L.

2011-12-01

Space weather's effects upon the near-Earth environment are due to dynamic changes in the energy transfer processes from the Sun's photons, particles, and fields. Of the space environment domains that are affected by space weather, the ionosphere is the key region that affects communication and navigation systems. The Utah State University (USU) Space Weather Center (SWC) is developing and producing commercial space weather applications. A key system-level component for providing timely information about the effects of space weather is the Global Assimilation of Ionospheric Measurements (GAIM) system. GAIM, operated by SWC, improves real-time communication and navigation systems by continuously ingesting up to 10,000 slant TEC measurements every 15-minutes from approximately 500 stations. Ionosonde data from several dozen global stations is ingested every 15 minutes to improve the vertical profiles within GAIM. The global, CONUS, Europe, Asia, South America, and other regional sectors are run with a 15-minute cadence. These operational runs enable SWC to calculate and report the global radio high frequency (HF) signal strengths and near vertical incidence skywave (NVIS) maps used by amateur radio operators and emergency responders, especially during the Japan Great Earthquake and tsunami recovery period. SWC has established its first fully commercial enterprise called Q-up as a result of this activity. GPS uncertainty maps are produced by SWC to improve single-frequency GPS applications. SWC also provides the space weather smartphone app called SpaceWx for iPhone, iPad, iPod, and Android for professional users and public space weather education. SpaceWx displays the real-time solar, heliosphere, magnetosphere, thermosphere, and ionosphere drivers to changes in the total electron content, for example, as well as global NVIS maps. We describe upcoming improvements for moving space weather information through automated systems into final derivative products.

A bio-inspired electrocommunication system for small underwater robots.

PubMed

Wang, Wei; Liu, Jindong; Xie, Guangming; Wen, Li; Zhang, Jianwei

2017-03-29

Weakly electric fishes (Gymnotid and Mormyrid) use an electric field to communicate efficiently (termed electrocommunication) in the turbid waters of confined spaces where other communication modalities fail. Inspired by this biological phenomenon, we design an artificial electrocommunication system for small underwater robots and explore the capabilities of such an underwater robotic communication system. An analytical model for electrocommunication is derived to predict the effect of the key parameters such as electrode distance and emitter current of the system on the communication performance. According to this model, a low-dissipation, and small-sized electrocommunication system is proposed and integrated into a small robotic fish. We characterize the communication performance of the robot in still water, flowing water, water with obstacles and natural water conditions. The results show that underwater robots are able to communicate electrically at a speed of around 1 k baud within about 3 m with a low power consumption (less than 1 W). In addition, we demonstrate that two leader-follower robots successfully achieve motion synchronization through electrocommunication in the three-dimensional underwater space, indicating that this bio-inspired electrocommunication system is a promising setup for the interaction of small underwater robots.

Optical processing for future computer networks

NASA Technical Reports Server (NTRS)

Husain, A.; Haugen, P. R.; Hutcheson, L. D.; Warrior, J.; Murray, N.; Beatty, M.

1986-01-01

In the development of future data management systems, such as the NASA Space Station, a major problem represents the design and implementation of a high performance communication network which is self-correcting and repairing, flexible, and evolvable. To obtain the goal of designing such a network, it will be essential to incorporate distributed adaptive network control techniques. The present paper provides an outline of the functional and communication network requirements for the Space Station data management system. Attention is given to the mathematical representation of the operations being carried out to provide the required functionality at each layer of communication protocol on the model. The possible implementation of specific communication functions in optics is also considered.

Information sciences and human factors overview

NASA Technical Reports Server (NTRS)

Holcomb, Lee B.

1988-01-01

An overview of program objectives of the Information Sciences and Human Factors Division of NASA's Office of Aeronautics and Space Technology is given in viewgraph form. Information is given on the organizational structure, goals, the research and technology base, telerobotics, systems autonomy in space operations, space sensors, humans in space, space communications, space data systems, transportation vehicle guidance and control, spacecraft control, and major program directions in space.

Artist concept of the STS-43 Tracking and Data Relay Satellite E (TDRS-E)

NASA Image and Video Library

1990-06-22

Artist concept shows the Tracking and Data Relay Satellite E (TDRS-E) augmenting a sophisticated TDRS system (TDRSS) communications network after deployment during STS-43 from Atlantis, Orbiter Vehicle (OV) 104. TDRS, built by TRW, will be placed in a geosynchronous orbit and after onorbit testing, which requires several weeks, will be designated TDRS-5. The communications satellite will replace TDRS-3 at 174 degrees West longitude. The backbone of NASA's space-to-ground communications, the TDRSs have increased NASA's ability to send and receive data to spacecraft in low-earth orbit to more than 85 percent of the time. Before TDRS, NASA relied solely on a system of ground stations that permitted communications only 15 percent of the time. Increased coverage has allowed onorbit repairs, live television broadcast from space and continuous dialogues between astronaut crews and ground control during critical periods such as Space Shuttle landings.

Monolithic microwave integrated circuits for sensors, radar, and communications systems; Proceedings of the Meeting, Orlando, FL, Apr. 2-4, 1991

NASA Technical Reports Server (NTRS)

Leonard, Regis F. (Editor); Bhasin, Kul B. (Editor)

1991-01-01

Consideration is given to MMICs for airborne phased arrays, monolithic GaAs integrated circuit millimeter wave imaging sensors, accurate design of multiport low-noise MMICs up to 20 GHz, an ultralinear low-noise amplifier technology for space communications, variable-gain MMIC module for space applications, a high-efficiency dual-band power amplifier for radar applications, a high-density circuit approach for low-cost MMIC circuits, coplanar SIMMWIC circuits, recent advances in monolithic phased arrays, and system-level integrated circuit development for phased-array antenna applications. Consideration is also given to performance enhancement in future communications satellites with MMIC technology insertion, application of Ka-band MMIC technology for an Orbiter/ACTS communications experiment, a space-based millimeter wave debris tracking radar, low-noise high-yield octave-band feedback amplifiers to 20 GHz, quasi-optical MESFET VCOs, and a high-dynamic-range mixer using novel balun structure.

Aerospace Applications Conference, Steamboat Springs, CO, Feb. 1-8, 1986, Digest

NASA Astrophysics Data System (ADS)

The present conference considers topics concerning the projected NASA Space Station's systems, digital signal and data processing applications, and space science and microwave applications. Attention is given to Space Station video and audio subsystems design, clock error, jitter, phase error and differential time-of-arrival in satellite communications, automation and robotics in space applications, target insertion into synthetic background scenes, and a novel scheme for the computation of the discrete Fourier transform on a systolic processor. Also discussed are a novel signal parameter measurement system employing digital signal processing, EEPROMS for spacecraft applications, a unique concurrent processor architecture for high speed simulation of dynamic systems, a dual polarization flat plate antenna, Fresnel diffraction, and ultralinear TWTs for high efficiency satellite communications.

A technology assessment of alternative communications systems for the space exploration initiative

NASA Technical Reports Server (NTRS)

Ponchak, Denise S.; Zuzek, John E.; Whyte, Wayne A., Jr.; Spence, Rodney L.; Sohn, Philip Y.

1990-01-01

Telecommunications, Navigation, and Information Management (TNIM) services are vital to accomplish the ambitious goals of the Space Exploration Initiative (SEI). A technology assessment is provided for four alternative lunar and Mars operational TNIM systems based on detailed communications link analyses. The four alternative systems range from a minimum to a fully enhanced capability and use frequencies from S-band, through Ka-band, and up to optical wavelengths. Included are technology development schedules as they relate to present SEI mission architecture time frames.

The Telecommunications and Data Acquisition Report

NASA Technical Reports Server (NTRS)

Posner, E. C. (Editor)

1984-01-01

This publication provides reports on work performed for the Office of Space Tracking and Data Systems (OSTDS). It reports on the activities of the deep space network (DSN) and the Ground Communications Facility (GCF). Topics discussed on the operation of the DSN include: (1) spacecraft-ground communications; (2) station control and system technology; and (3) capabilities for new projects for systems implementation. The GCF compatibility with packets and data compression is discussed. In geodynamics, the publication reports on the application of radio interferometry at microwave frequencies for geodynamic measurements.

Image Capture and Display Based on Embedded Linux

NASA Astrophysics Data System (ADS)

Weigong, Zhang; Suran, Di; Yongxiang, Zhang; Liming, Li

For the requirement of building a highly reliable communication system, SpaceWire was selected in the integrated electronic system. There was a need to test the performance of SpaceWire. As part of the testing work, the goal of this paper is to transmit image data from CMOS camera through SpaceWire and display real-time images on the graphical user interface with Qt in the embedded development platform of Linux & ARM. A point-to-point mode of transmission was chosen; the running result showed the two communication ends basically reach a consensus picture in succession. It suggests that the SpaceWire can transmit the data reliably.

The Deep Space Network, volume 17

NASA Technical Reports Server (NTRS)

1973-01-01

The objectives, functions, and organization of the Deep Space Network are summarized. The Deep Space Instrumentation Facility, the Ground Communications Facility, and the Network Control System are described.

A Common Communications, Navigation and Surveillance Infrastructure for Accommodating Space Vehicles in the Next Generation Air Transportation System

NASA Technical Reports Server (NTRS)

VanSuetendael, RIchard; Hayes, Alan; Birr, Richard

2008-01-01

Suborbital space flight and space tourism are new potential markets that could significantly impact the National Airspace System (NAS). Numerous private companies are developing space flight capabilities to capture a piece of an emerging commercial space transportation market. These entrepreneurs share a common vision that sees commercial space flight as a profitable venture. Additionally, U.S. space exploration policy and national defense will impose significant additional demands on the NAS. Air traffic service providers must allow all users fair access to limited airspace, while ensuring that the highest levels of safety, security, and efficiency are maintained. The FAA's Next Generation Air Transportation System (NextGen) will need to accommodate spacecraft transitioning to and from space through the NAS. To accomplish this, space and air traffic operations will need to be seamlessly integrated under some common communications, navigation and surveillance (CNS) infrastructure. As part of NextGen, the FAA has been developing the Automatic Dependent Surveillance Broadcast (ADS-B) which utilizes the Global Positioning System (GPS) to track and separate aircraft. Another key component of NextGen, System-Wide Information Management/ Network Enabled Operations (SWIM/NEO), is an open architecture network that will provide NAS data to various customers, system tools and applications. NASA and DoD are currently developing a space-based range (SBR) concept that also utilizes GPS, communications satellites and other CNS assets. The future SBR will have very similar utility for space operations as ADS-B and SWIM has for air traffic. Perhaps the FAA, NASA, and DoD should consider developing a common space-based CNS infrastructure to support both aviation and space transportation operations. This paper suggests specific areas of research for developing a CNS infrastructure that can accommodate spacecraft and other new types of vehicles as an integrated part of NextGen.

Design of a stabilized, compact gimbal for space-based free space optical communications (FSOC)

NASA Astrophysics Data System (ADS)

Cline, A.; Shubert, P.; McNally, J.; Jacka, N.; Pierson, R.

2017-02-01

Data transmits via optical communications through fibers at 10's of Terabits per second. Given the recent rapid explosion for bandwidth and competing demand for radio frequency (RF) spectrum allocations among differing interests, the need for space-based free space optical communications (FSOC) systems is ever increasing. FSOC systems offer advantages of higher data rates, smaller size and weight, narrower beam divergence, and lower power than RF systems. Lightweight, small form factor, and high performance two-axis gimbals are of strong interest for satellite FSOC applications. Small gimbal and optical terminal designs are important for widespread implementation of optical communications systems; in particular, for satellite-to-satellite crosslinks where the advantages of more secure communications links (Lower Probability of Intercept (LPI)/Lower Probability of Detect (LPD)) are very important. We developed design concepts for a small gimbal focusing on the use of commercial off-the-shelf (COTS) subsystems to establish their feasible implementation against the pointing stabilization, size, weight and power (SWaP), and performance challenges. The design drivers for the gimbal were weight, the elevation and azimuth field of regards, the form factor envelope (1U CubeSats), 100 μrad pointing accuracy, and 10 degrees per second slew capability. Innovations required in this development included a continuous fiber passed through an Azimuth Fiber Wrap and Elevation Fiber Wrap, overcoming typical mechanical and stress related limitations encountered with fiber optic cable wraps. In this presentation, we describe the configuration trades and design of such a gimbal.

Conformal, Transparent Printed Antenna Developed for Communication and Navigation Systems

NASA Technical Reports Server (NTRS)

Lee, Richard Q.; Simons, Rainee N.

1999-01-01

Conformal, transparent printed antennas have advantages over conventional antennas in terms of space reuse and aesthetics. Because of their compactness and thin profile, these antennas can be mounted on video displays for efficient integration in communication systems such as palmtop computers, digital telephones, and flat-panel television displays. As an array of multiple elements, the antenna subsystem may save weight by reusing space (via vertical stacking) on photovoltaic arrays or on Earth-facing sensors. Also, the antenna could go unnoticed on automobile windshields or building windows, enabling satellite uplinks and downlinks or other emerging high-frequency communications.

An Optimum Space-to-Ground Communication Concept for CubeSat Platform Utilizing NASA Space Network and Near Earth Network

NASA Technical Reports Server (NTRS)

Wong, Yen F.; Kegege, Obadiah; Schaire, Scott H.; Bussey, George; Altunc, Serhat; Zhang, Yuwen; Patel Chitra

2016-01-01

National Aeronautics and Space Administration (NASA) CubeSat missions are expected to grow rapidly in the next decade. Higher data rate CubeSats are transitioning away from Amateur Radio bands to higher frequency bands. A high-level communication architecture for future space-to-ground CubeSat communication was proposed within NASA Goddard Space Flight Center. This architecture addresses CubeSat direct-to-ground communication, CubeSat to Tracking Data Relay Satellite System (TDRSS) communication, CubeSat constellation with Mothership direct-to-ground communication, and CubeSat Constellation with Mothership communication through K-Band Single Access (KSA). A study has been performed to explore this communication architecture, through simulations, analyses, and identifying technologies, to develop the optimum communication concepts for CubeSat communications. This paper presents details of the simulation and analysis that include CubeSat swarm, daughter ship/mother ship constellation, Near Earth Network (NEN) S and X-band direct to ground link, TDRSS Multiple Access (MA) array vs Single Access mode, notional transceiver/antenna configurations, ground asset configurations and Code Division Multiple Access (CDMA) signal trades for daughter ship/mother ship CubeSat constellation inter-satellite cross link. Results of space science X-band 10 MHz maximum achievable data rate study are summarized. CubeSat NEN Ka-Band end-to-end communication analysis is provided. Current CubeSat communication technologies capabilities are presented. Compatibility test of the CubeSat transceiver through NEN and SN is discussed. Based on the analyses, signal trade studies and technology assessments, the desired CubeSat transceiver features and operation concepts for future CubeSat end-to-end communications are derived.

The architecture of blind equalizer for MIMO free space optical communication system

NASA Astrophysics Data System (ADS)

Li, Hongwei; Huang, Yongmei

2016-10-01

The free space optical (FSO) communication system has attracted many researchers from different countries, owning to its advantages such as high security, high speed and anti-interference. Among all kinds of the channels of the FSO communication system, the atmosphere channel is very difficult to deal with for two typical disadvantages at least. The one is the scintillation of the optical carrier intensity caused by the atmosphere turbulence and the other is the multipath effect by the optical scattering. A lot of studies have shown that the MIMO (Multiple Input Multiple Output) technology can overcome the scintillation of the optical carrier through the atmosphere effectively. So the background of this paper is a MIMO system which includes multiple optical transmitting antennas and multiple optical receiving antennas. A number of particles such as hazes, water droplets and aerosols exit in the atmosphere widely. When optical carrier meets these particles, the scattering phenomenon is inevitable, which leads to the multipath effect. As a result, a optical pulse transmitted by the optical transmitter becomes wider, to some extent, when it gets to the optical receiver due to the multipath effect. If the information transmission rate is quite low, there is less relationship between the multipath effect and the bit error rate (BER) of the communication system. Once the information transmission rate increases to a high level, the multipath effect will produce the problem called inter symbol inference (ISI) seriously and the bit error rate will increase severely. In order to take the advantage of the FSO communication system, the inter symbol inference problem must be solved. So it is necessary to use the channel equalization technology. This paper aims at deciding a equalizer and designing suitable equalization algorithm for a MIMO free space optical communication system to overcome the serious problem of bit error rate. The reliability and the efficiency of communication are two important indexes. For a MIMO communication system, there are two typical equalization methods. The first method, every receiving antenna has an independent equalizer without the information derived from the other receiving antennas. The second, the information derived from all of the receiving antennas mixes with each other, according to some definite rules, which is called space-time equalization. The former is discussed in this paper. The equalization algorithm concludes training mode and non training mode. The training mode needs training codes transmitted by the transmitter during the whole communication process and this mode reduces the communication efficiency more or less. In order to improve the communication efficiency, the blind equalization algorithm, a non training mode, is used to solve the parameter of the equalizer. In this paper, firstly, the atmosphere channel is described focusing on the scintillation and multipath effect of the optical carrier. Then, the structure of a equalizer of MIMO free space optical communication system is introduced. In the next part of this paper, the principle of the blind equalization algorithm is introduced. In addition, the simulation results are showed. In the end of this paper, the conclusions and the future work are discussed.

The optical antenna system design research on earth integrative network laser link in the future

NASA Astrophysics Data System (ADS)

Liu, Xianzhu; Fu, Qiang; He, Jingyi

2014-11-01

Earth integrated information network can be real-time acquisition, transmission and processing the spatial information with the carrier based on space platforms, such as geostationary satellites or in low-orbit satellites, stratospheric balloons or unmanned and manned aircraft, etc. It is an essential infrastructure for China to constructed earth integrated information network. Earth integrated information network can not only support the highly dynamic and the real-time transmission of broadband down to earth observation, but the reliable transmission of the ultra remote and the large delay up to the deep space exploration, as well as provide services for the significant application of the ocean voyage, emergency rescue, navigation and positioning, air transportation, aerospace measurement or control and other fields.Thus the earth integrated information network can expand the human science, culture and productive activities to the space, ocean and even deep space, so it is the global research focus. The network of the laser communication link is an important component and the mean of communication in the earth integrated information network. Optimize the structure and design the system of the optical antenna is considered one of the difficulty key technologies for the space laser communication link network. Therefore, this paper presents an optical antenna system that it can be used in space laser communication link network.The antenna system was consisted by the plurality mirrors stitched with the rotational paraboloid as a substrate. The optical system structure of the multi-mirror stitched was simulated and emulated by the light tools software. Cassegrain form to be used in a relay optical system. The structural parameters of the relay optical system was optimized and designed by the optical design software of zemax. The results of the optimal design and simulation or emulation indicated that the antenna system had a good optical performance and a certain reference value in engineering. It can provide effective technical support to realize interconnection of earth integrated laser link information network in the future.

Performance analysis of 1-km free-space optical communication system over real atmospheric turbulence channels

NASA Astrophysics Data System (ADS)

Liu, Dachang; Wang, Zixiong; Liu, Jianguo; Tan, Jun; Yu, Lijuan; Mei, Haiping; Zhou, Yusong; Zhu, Ninghua

2017-10-01

The performance of a free-space optical communication system is highly affected by the atmospheric turbulence in terms of scintillation. An optical communication system based on intensity-modulation direct-detection was built with 1-km transmission distance to evaluate the bit error rate (BER) performance over real atmospheric turbulence. 2.5-, 5-, and 10-Gbps data rate transmissions were carried out, where error-free transmission could be achieved during over 37% of the 2.5-Gbps transmissions and over 43% of the 5-Gbps transmissions. In the rest of the transmissions, BER deteriorated as the refractive-index structure constant increased, while the two measured items have almost the same trend.

Dimensional discontinuity in quantum communication complexity at dimension seven

NASA Astrophysics Data System (ADS)

Tavakoli, Armin; Pawłowski, Marcin; Żukowski, Marek; Bourennane, Mohamed

2017-02-01

Entanglement-assisted classical communication and transmission of a quantum system are the two quantum resources for information processing. Many information tasks can be performed using either quantum resource. However, this equivalence is not always present since entanglement-assisted classical communication is sometimes known to be the better performing resource. Here, we show not only the opposite phenomenon, that there exist tasks for which transmission of a quantum system is a more powerful resource than entanglement-assisted classical communication, but also that such phenomena can have a surprisingly strong dependence on the dimension of Hilbert space. We introduce a family of communication complexity problems parametrized by the dimension of Hilbert space and study the performance of each quantum resource. Under an additional assumption of a linear strategy for the receiving party, we find that for low dimensions the two resources perform equally well, whereas for dimension seven and above the equivalence is suddenly broken and transmission of a quantum system becomes more powerful than entanglement-assisted classical communication. Moreover, we find that transmission of a quantum system may even outperform classical communication assisted by the stronger-than-quantum correlations obtained from the principle of macroscopic locality.

Short-range communication system

NASA Technical Reports Server (NTRS)

Alhorn, Dean C. (Inventor); Howard, David E. (Inventor); Smith, Dennis A. (Inventor)

2012-01-01

A short-range communication system includes an antenna, a transmitter, and a receiver. The antenna is an electrical conductor formed as a planar coil with rings thereof being uniformly spaced. The transmitter is spaced apart from the plane of the coil by a gap. An amplitude-modulated and asynchronous signal indicative of a data stream of known peak amplitude is transmitted into the gap. The receiver detects the coil's resonance and decodes same to recover the data stream.

Monolithic microwave integrated circuit technology for advanced space communication

NASA Technical Reports Server (NTRS)

Ponchak, George E.; Romanofsky, Robert R.

1988-01-01

Future Space Communications subsystems will utilize GaAs Monolithic Microwave Integrated Circuits (MMIC's) to reduce volume, weight, and cost and to enhance system reliability. Recent advances in GaAs MMIC technology have led to high-performance devices which show promise for insertion into these next generation systems. The status and development of a number of these devices operating from Ku through Ka band will be discussed along with anticipated potential applications.

Design of a Combined Beacon Receiver and Digital Radiometer for 40 GHz Propagation Measurements at the Madrid Deep Space Communications Complex

NASA Technical Reports Server (NTRS)

Zemba, Michael J.; Nessel, James A.; Morabito, David D.

2017-01-01

NASA Glenn Research Center (GRC) and the Jet Propulsion Laboratory (JPL) have jointly developed an atmospheric propagation terminal to measure and characterize propagation phenomena at 40 GHz at the Madrid Deep Space Communications Complex (MDSCC) in Robledo de Chavela, Spain. The hybrid Q-band system combines a 40 GHz beacon receiver and digital radiometer into the same RF front-end and observes the 39.402 GHz beacon of the European Space Agencys Alphasat Aldo Paraboni TDP5 experiment. The goals of these measurements are to assist MDSCC mission operations as well as to contribute to the development and improvement of International Telecommunications Union (ITU) models for prediction of communications systems performance within the Q-band. Herein, we provide an overview of the system design, characterization, and plan of operations to commence at the MDSCC beginning in March 2017.

Towards Co-Engineering Communicating Autonomous Cyber-Physical Systems

NASA Technical Reports Server (NTRS)

Bujorianu, Marius C.; Bujorianu, Manuela L.

2009-01-01

In this paper, we sketch a framework for interdisciplinary modeling of space systems, by proposing a holistic view. We consider different system dimensions and their interaction. Specifically, we study the interactions between computation, physics, communication, uncertainty and autonomy. The most comprehensive computational paradigm that supports a holistic perspective on autonomous space systems is given by cyber-physical systems. For these, the state of art consists of collaborating multi-engineering efforts that prompt for an adequate formal foundation. To achieve this, we propose a leveraging of the traditional content of formal modeling by a co-engineering process.

Considerations in the design of a communication network for an autonomously managed power system

NASA Technical Reports Server (NTRS)

Mckee, J. W.; Whitehead, Norma; Lollar, Louis

1989-01-01

The considerations involved in designing a communication network for an autonomously managed power system intended for use in space vehicles are examined. An overview of the design and implementation of a communication network implemented in a breadboard power system is presented. An assumption that the monitoring and control devices are distributed but physically close leads to the selection of a multidrop cable communication system. The assumption of a high-quality communication cable in which few messages are lost resulted in a simple recovery procedure consisting of a time out and retransmit process.

Developing Systems Engineering Skills Through NASA Summer Intern Project

NASA Technical Reports Server (NTRS)

Bhasin, Kul; Barritt, Brian; Golden, Bert; Knoblock, Eric; Matthews, Seth; Warner, Joe

2010-01-01

During the Formulation phases of the NASA Project Life Cycle, communication systems engineers are responsible for designing space communication links and analyzing their performance to ensure that the proposed communication architecture is capable of satisfying high-level mission requirements. Senior engineers with extensive experience in communications systems perform these activities. However, the increasing complexity of space systems coupled with the current shortage of communications systems engineers has led to an urgent need for expedited training of new systems engineers. A pilot program, in which college-bound high school and undergraduate students studying various engineering disciplines are immersed in NASA s systems engineering practices, was conceived out of this need. This rapid summerlong training approach is feasible because of the availability of advanced software and technology tools and the students inherent ability to operate such tools. During this pilot internship program, a team of college-level and recently-hired engineers configured and utilized various software applications in the design and analysis of communication links for a plausible lunar sortie mission. The approach taken was to first design the direct-to-Earth communication links for the lunar mission elements, then to design the links between lunar surface and lunar orbital elements. Based on the data obtained from these software applications, an integrated communication system design was realized and the students gained valuable systems engineering knowledge. This paper describes this approach to rapidly training college-bound high school and undergraduate engineering students from various disciplines in NASA s systems engineering practices and tools. A summary of the potential use of NASA s emerging systems engineering internship program in broader applications is also described.

Development and Characterization of a Small Spacecraft Electro-Optic Scanner for Free-Space Laser Communications

NASA Technical Reports Server (NTRS)

Davis, Scott; Lichter, Michael; Raible, Daniel

2016-01-01

Emergent data-intensive missions coupled with dramatic reductions in spacecraft size plus an increasing number of space-based missions necessitates new high performance, compact and low cost communications technology. Free space optical communications offer advantages including orders of magnitude increase for data rate performance, increased security, immunity to jamming and lack of frequency allocation requirements when compared with conventional radio frequency (RF) means. The spatial coherence and low divergence associated with the optical frequencies of laser communications lends themselves to superior performance, but this increased directionality also creates one of the primary technical challenges in establishing a laser communications link by repeatedly and reliably pointing the beam onto the receive aperture. Several solutions have emerged from wide angle (slow) mechanical articulation systems, fine (fast) steering mirrors and rotating prisms, inertial compensation gyros and vibration isolation cancellation systems, but each requires moving components and imparts a measured amount of burden on the host platform. The complexity, cost and size of current mechanically scanned solutions limits their platform applicability, and restricts the feasibility of deploying optical communications payloads on very compact spacecraft employing critical systems. A high speed, wide angle, non-mechanical solution is therefore desirable. The purpose of this work is to share the development, testing, and demonstration of a breadboard prototype electro-optic (EO) scanned laser-communication link (see Figure 1). This demonstration is a step toward realizing ultra-low Size, Weight and Power (SWaP) SmallSat/MicroSat EO non-mechanical laser beam steering modules for high bandwidth ( greater than Gbps) free-space data links operating in the 1550 nm wavelength bands. The elimination of all moving parts will dramatically reduce SWaP and cost, increase component lifetime and reliability, and simplify the system design of laser communication modules. This paper describes the target mission architectures and requirements (few cubic centimeters of volume, 10's of grams of weight with milliwatts of power) and design of the beam steering module. Laboratory metrology is used to determine the component performance including horizontal and vertical resolution (20urad) as a function of control voltage (see Figure 2), transition time (0.1-1ms), pointing repeatability and optic insertion loss. A test bed system demonstration, including a full laser communications link, is conducted. The capabilities of this new EO beam steerer provide an opportunity to dramatically improve space communications through increased utilization of laser technology on smaller platforms than were previously attainable.

The deep space network

NASA Technical Reports Server (NTRS)

1977-01-01

The facilities, programming system, and monitor and control system for the deep space network are described. Ongoing planetary and interplanetary flight projects are reviewed, along with tracking and ground-based navigation, communications, and network and facility engineering.

Space Communications and Data Systems Technologies for Next Generation Earth Science Measurements

NASA Technical Reports Server (NTRS)

Bauer, Robert A.; Reinhart, Richard C.; Hilderman, Don R.; Paulsen, Phillip E.

2003-01-01

The next generation of Earth observing satellites and sensor networks will face challenges in supporting robust high rate communications links from the increasingly sophisticated onboard instruments. Emerging applications will need data rates forecast to be in the 100's to 1000's of Mbps. As mission designers seek smaller spacecraft, challenges exist in reducing the size and power requirements while increasing the capacity of the spacecraft's communications technologies. To meet these challenges, this work looks at three areas of selected space communications and data services technologies, specifically in the development of reflectarray antennas, demonstration of space Internet concepts, and measurement of atmospheric propagation effects on Ka-band signal transmitted from LEO.

Operational System-Impact Products for the Space Situational Awareness Environmental Effects Fusion System (SEEFS)

NASA Astrophysics Data System (ADS)

Quigley, S.; Scro, K.

2006-12-01

The Space Vehicles Directorate of the Air Force Research Laboratory (AFRL/VSBX) and the Technology Applications Division of the Space and Missile Systems Center (SMC/WXT) have combined efforts under the Rapid Prototyping Center (RPC) to design, develop, test, implement, and validate numerical and graphical products for the Air Force Space Command (AFSPC) Space Situational Awareness Environmental Effects Fusion System (SEEFS). These products are generated to analyze, specify, and forecast the effects of the near-earth space environment on Department of Defense weapons, navigation, communications, and surveillance systems. Jointly developed projects that have been completed as prototypes and are undergoing development for real-time operations include a SEEFS architecture and database, five system-impact products, and a high-level decision aid product. This first round of SEEFS products includes Solar Radio Burst Effects (SoRBE) on radar and satellite communications, Radar Auroral Clutter (RAC), Scintillation Effects on radar and satellite communications (RadScint and SatScint), and Satellite Surface and Deep Charge/Discharge (Char/D). The SEEFS architecture and database enable modular use and execution of SEEFS products, and the high-level Decision Aid shows the combined effects of all SEEFS product output on a given asset and on multi-asset missions. This presentation provides a general overview of the SEEFS program, along with details of the first round of products expected to be operational for use in exercises and/or real-time operations in 2007-2008.

Microprocessor-Based Systems Control for the Rigidized Inflatable Get-Away-Special Experiment

DTIC Science & Technology

2004-03-01

communications and faster data throughput increase, satellites are becoming larger. Larger satellite antennas help to provide the needed gain to...increase communications in space. Compounding the performance and size trade-offs are the payload weight and size limit imposed by the launch vehicles...increased communications capacity, and reduce launch costs. This thesis develops and implements the computer control system and power system to

KSC-02pd1579

NASA Image and Video Library

2002-10-18

KENNEDY SPACE CENTER, FLA. - The TDRS-J spacecraft, enclosed in a container, arrives at the Spacecraft Assembly and Encapsulation Facility-2 (SAEF-2) for processing. The Tracking and Data Relay Satellite System is the primary source of space-to-ground voice, data and telemetry for the Space Shuttle. It also provides communications with the International Space Station and scientific spacecraft in low-earth orbit such as the Hubble Space Telescope, and launch support for some expendable vehicles. This new advanced series of satellites will extend the availability of TDRS communications services until approximately 2017.

Space safety and rescue 1979-1981: Worldwide disaster response, rescue and safety employing space-borne systems

NASA Technical Reports Server (NTRS)

Brown, J. W. (Editor)

1983-01-01

Selected papers from the 1979, 1980, and 1981 IAA symposia on space safety and rescue and on worldwide disaster response, safety, and rescue employing spaceborne systems are presented. Available papers published elsewhere and those presented at the 1976, 1977, and 1978 symposia are presented in abstract form. Subjects discussed include man-made space debris, nuclear-waste disposal in space, space-station safety design, psychological training, the introduction of female crewmembers, analysis of the November 23, 1980 earthquake as a design basis for satellite emergency communication, disaster warning using the GOES satellite, and satellite communications for disaster relief operations. Three reviews of the application of space technology to emergency and disaster relief and prevention, given at other symposia in 1981, are presented in an appendix. No individual items are abstracted in this volume

The Deep Space Network

NASA Technical Reports Server (NTRS)

1974-01-01

The objectives, functions, and organization, of the Deep Space Network are summarized. Deep Space stations, ground communications, and network operations control capabilities are described. The network is designed for two-way communications with unmanned spacecraft traveling approximately 1600 km from earth to the farthest planets in the solar system. It has provided tracking and data acquisition support for the following projects: Ranger, Surveyor, Mariner, Pioneer, Apollo, Helios, Viking, and the Lunar Orbiter.

Partnering to Change the Way NASA and the Nation Communicate Through Space

NASA Technical Reports Server (NTRS)

Vrotsos, Pete A.; Budinger, James M.; Bhasin, Kul; Ponchak, Denise S.

2000-01-01

For at least 20 years, the Space Communications Program at NASA Glenn Research Center (GRC) has focused on enhancing the capability and competitiveness of the U.S. commercial communications satellite industry. GRC has partnered with the industry on the development of enabling technologies to help maintain U.S. preeminence in the worldwide communications satellite marketplace. The Advanced Communications Technology Satellite (ACTS) has been the most significant space communications technology endeavor ever performed at GRC, and the centerpiece of GRC's communication technology program for the last decade. Under new sponsorship from NASA's Human Exploration and Development of Space Enterprise, GRC has transitioned the focus and direction of its program, from commercial relevance to NASA mission relevance. Instead of one major experimental spacecraft and one headquarters sponsor, GRC is now exploring opportunities for all of NASA's Enterprises to benefit from advances in space communications technologies, and accomplish their missions through the use of existing and emerging commercially provided services. A growing vision within NASA is to leverage the best commercial standards, technologies, and services as a starting point to satisfy NASA's unique needs. GRC's heritage of industry partnerships is closely aligned with this vision. NASA intends to leverage the explosive growth of the telecommunications industry through its impressive technology advancements and potential new commercial satellite systems. GRC's partnerships with the industry, academia, and other government agencies will directly support all four NASA's future mission needs, while advancing the state of the art of commercial practice. GRC now conducts applied research and develops and demonstrates advanced communications and network technologies in support of all four NASA Enterprises (Human Exploration and Development of Space, Space Science, Earth Science, and Aero-Space Technologies).

High Precision Ranging and Range-Rate Measurements over Free-Space-Laser Communication Link

NASA Technical Reports Server (NTRS)

Yang, Guangning; Lu, Wei; Krainak, Michael; Sun, Xiaoli

2016-01-01

We present a high-precision ranging and range-rate measurement system via an optical-ranging or combined ranging-communication link. A complete bench-top optical communication system was built. It included a ground terminal and a space terminal. Ranging and range rate tests were conducted in two configurations. In the communication configuration with 622 data rate, we achieved a two-way range-rate error of 2 microns/s, or a modified Allan deviation of 9 x 10 (exp -15) with 10 second averaging time. Ranging and range-rate as a function of Bit Error Rate of the communication link is reported. They are not sensitive to the link error rate. In the single-frequency amplitude modulation mode, we report a two-way range rate error of 0.8 microns/s, or a modified Allan deviation of 2.6 x 10 (exp -15) with 10 second averaging time. We identified the major noise sources in the current system as the transmitter modulation injected noise and receiver electronics generated noise. A new improved system will be constructed to further improve the system performance for both operating modes.

Space Power

NASA Technical Reports Server (NTRS)

1984-01-01

Appropriate directions for the applied research and technology programs that will develop space power systems for U.S. future space missions beyond 1995 are explored. Spacecraft power supplies; space stations, space power reactors, solar arrays, thermoelectric generators, energy storage, and communication satellites are among the topics discussed.

The Telecommunications and Data Acquisition Report

NASA Technical Reports Server (NTRS)

Posner, E. C. (Editor)

1990-01-01

Archival reports on developments in programs managed by the Jet Propulsion Laboratory's (JPL) Office of Telecommunications and Data Acquisition (TDA) are given. Space communications, radio navigation, radio science, and ground-based radio and radar astronomy, activities of the Deep Space Network (DSN) and its associated Ground Communications Facility (GCF) in planning, supporting research and technology, implementation, and operations are reported. Also included is TDA-funded activity at JPL on data and information systems and reimbursable Deep Space Network (DSN) work performed for other space agencies through NASA.

Space-Based Optical Communications with CubeSats

NASA Technical Reports Server (NTRS)

Ebert, Monica L.; Nguyen, Anh Ngoc; Frost, Chad

2017-01-01

Optical communication systems use lasers to encode and transmit data with higher speed and density than traditional radio frequency (RF)-based communications. Smaller antennas, lower power requirements, and increased spectrum availability enable optical communications to be integrated into CubeSats more easily than radios, enabling afford-able communications solutions for future NASA missions.

SpaceWire- Based Control System Architecture for the Lightweight Advanced Robotic Arm Demonstrator [LARAD

NASA Astrophysics Data System (ADS)

Rucinski, Marek; Coates, Adam; Montano, Giuseppe; Allouis, Elie; Jameux, David

2015-09-01

The Lightweight Advanced Robotic Arm Demonstrator (LARAD) is a state-of-the-art, two-meter long robotic arm for planetary surface exploration currently being developed by a UK consortium led by Airbus Defence and Space Ltd under contract to the UK Space Agency (CREST-2 programme). LARAD has a modular design, which allows for experimentation with different electronics and control software. The control system architecture includes the on-board computer, control software and firmware, and the communication infrastructure (e.g. data links, switches) connecting on-board computer(s), sensors, actuators and the end-effector. The purpose of the control system is to operate the arm according to pre-defined performance requirements, monitoring its behaviour in real-time and performing safing/recovery actions in case of faults. This paper reports on the results of a recent study about the feasibility of the development and integration of a novel control system architecture for LARAD fully based on the SpaceWire protocol. The current control system architecture is based on the combination of two communication protocols, Ethernet and CAN. The new SpaceWire-based control system will allow for improved monitoring and telecommanding performance thanks to higher communication data rate, allowing for the adoption of advanced control schemes, potentially based on multiple vision sensors, and for the handling of sophisticated end-effectors that require fine control, such as science payloads or robotic hands.

Propagation effects handbook for satellite systems design. A summary of propagation impairments on 10 to 100 GHz satellite links with techniques for system design

NASA Technical Reports Server (NTRS)

Ippolito, Louis J.

1989-01-01

The NASA Propagation Effects Handbook for Satellite Systems Design provides a systematic compilation of the major propagation effects experienced on space-Earth paths in the 10 to 100 GHz frequency band region. It provides both a detailed description of the propagation phenomenon and a summary of the impact of the effect on the communications system design and performance. Chapter 2 through 5 describe the propagation effects, prediction models, and available experimental data bases. In Chapter 6, design techniques and prediction methods available for evaluating propagation effects on space-Earth communication systems are presented. Chapter 7 addresses the system design process and how the effects of propagation on system design and performance should be considered and how that can be mitigated. Examples of operational and planned Ku, Ka, and EHF satellite communications systems are given.

Potentials of RF/FSO Communication in UAS Operations

NASA Astrophysics Data System (ADS)

Griethe, Wolfgang; Heine, Frank

2013-08-01

Free Space Optical Communications (FSOC) has gained particular attention during the past few years and is progressing continuously. With the successful in-orbit verification of a Laser Communication Terminal (LCT), the coherent homodyne BPSK scheme advanced to a standard for Free-Space Optical Communication (FSOC) which now prevails more and more. The LCT is presently operated on satellites in Low Earth Orbit (LEO). In the near future, the LCT will be operated in Geosynchronous Orbit (GEO) onboard the ALPHASAT-TDP and the European Data Relay System (EDRS). In other words, the LCT has reached a point of maturity to realize its practical application. With existence of such space assets the time has come for other utilization beyond that of optical Inter-Satellite Links (ISL). Aeronautical applications, as for instance High Altitude Long Endurance (HALE) or Medium Altitude Long Endurance (MALE) Unmanned Aerial Systems (UAS) have to be addressed. This is caused due to an extremely high demand for bandwidth. Driving factors and advantages of FSOC in HALE/MALE UAS missions are highlighted. Numerous practice-related issues are described concerning the space segment, the aeronautical segment as well as the ground segment. The advantages for UAS missions are described resulting from the utilization of FSOC exclusively for wideband transmission of sensor data while vehicle Command & Control (C2) can be maintained, as before, via RF communication. Moreover, the paper discusses FSOC as an enabler for the integration of air and space-based wideband Intelligence, Surveillance & Reconnaissance (ISR) systems into existent military command and control networks. From the given information it can be concluded that FSOC contributes to the future increase of air-and space power.

Overview and Status of the Lunar Laser Communication Demonstration

NASA Technical Reports Server (NTRS)

Boroson, D. M.; Robinson, B. S.; Burianek, D. A.; Murphy, D. V.; Biswas, A.

2012-01-01

The Lunar Laser Communication Demonstration (LLCD), a project being undertaken by MIT Lincoln Laboratory, NASA's Goddard Space Flight Center, and the Jet Propulsion Laboratory, will be NASA's first attempt to demonstrate optical communications between a lunar orbiting spacecraft and Earth-based ground receivers. The LLCD space terminal will be flown on the Lunar Atmosphere and Dust Environment Explorer (LADEE) spacecraft, presently scheduled to launch in 2013. LLCD will demonstrate downlink optical communications at rates up to 620 Mbps, uplink optical communications at rates up to 20 Mbps, and two-way time-of-flight measurements with the potential to perform ranging with sub-centimeter accuracy. We describe the objectives of the LLCD program, key technologies employed in the space and ground terminals, and show the status of development of the several systems.

The Telecommunications and Data Acquisition Progress Report 42-123

NASA Technical Reports Server (NTRS)

Yuen, Joseph H. (Editor)

1995-01-01

The progress of research programs monitored by the Jet Propulsion Laboratory's Telecommunications and Mission Operations Directorate (TMOD) are presented in this quarterly document. Areas monitored include space communications, radio navigation, radio science, ground-based radio and radar astronomy, information systems, and all other communication and research technology activities for the Deep Space Network (DSN).

41 CFR 102-73.190 - What types of special purpose space may the Federal Communications Commission lease?

Code of Federal Regulations, 2010 CFR

2010-07-01

... 41 Public Contracts and Property Management 3 2010-07-01 2010-07-01 false What types of special purpose space may the Federal Communications Commission lease? 102-73.190 Section 102-73.190 Public Contracts and Property Management Federal Property Management Regulations System (Continued) FEDERAL...

Communications satellite systems operations with the space station. Volume 3: Supplementary technical report

NASA Technical Reports Server (NTRS)

Price, K. M.; Russell, P.; Weyandt, C.

1988-01-01

The NASA space station has the potential to provide significant economic benefits to commercial communications satellite operators. The initial reports qunatified the benefits of space-based activities and assessed the impacts on the satellite design and the space station. Results are given for the following additional tasks: quantify the value of satellite retrievability operations and define its operational aspects; evaluate the use of expendable launch vehicles for transportation of satellites from the Earth to the space station; and quantify the economic value of modular satellites that are assembled and serviced in space.

Coping with data from Space Station Freedom

NASA Technical Reports Server (NTRS)

Johnson, Marjory J.

1991-01-01

The volume of data from future NASA space missions will be phenomenal. Here, we examine the expected data flow from the Space Station Freedom and describe techniques that are being developed to transport and process that data. Networking in space, the Tracking and Data Relay Satellite System (TDRSS), recommendations of the Consultative Committee for Space Data systems (CCSDS), NASA institutional ground support, communications system architecture, and principal data types and formats are discussed.

On a two-pass scheme without a faraday mirror for free-space relativistic quantum cryptography

DOE Office of Scientific and Technical Information (OSTI.GOV)

Kravtsov, K. S.; Radchenko, I. V.; Korol'kov, A. V.

2013-05-15

The stability of destructive interference independent of the input polarization and the state of a quantum communication channel in fiber optic systems used in quantum cryptography plays a principal role in providing the security of communicated keys. A novel optical scheme is proposed that can be used both in relativistic quantum cryptography for communicating keys in open space and for communicating them over fiber optic lines. The scheme ensures stability of destructive interference and admits simple automatic balancing of a fiber interferometer.

Space-Based Telemetry and Range Safety Project Ku-Band and Ka-Band Phased Array Antenna

NASA Technical Reports Server (NTRS)

Whiteman, Donald E.; Valencia, Lisa M.; Birr, Richard B.

2005-01-01

The National Aeronautics and Space Administration Space-Based Telemetry and Range Safety study is a multiphase project to increase data rates and flexibility and decrease costs by using space-based communications assets for telemetry during launches and landings. Phase 1 used standard S-band antennas with the Tracking and Data Relay Satellite System to obtain a baseline performance. The selection process and available resources for Phase 2 resulted in a Ku-band phased array antenna system. Several development efforts are under way for a Ka-band phased array antenna system for Phase 3. Each phase includes test flights to demonstrate performance and capabilities. Successful completion of this project will result in a set of communications requirements for the next generation of launch vehicles.

Ku- and Ka-Band Phased Array Antenna for the Space-Based Telemetry and Range Safety Project

NASA Technical Reports Server (NTRS)

Whiteman, Donald E.; Valencia, Lisa M.; Birr, Richard B.

2005-01-01

The National Aeronautics and Space Administration Space-Based Telemetry and Range Safety study is a multiphase project to increase data rates and flexibility and decrease costs by using space-based communications assets for telemetry during launches and landings. Phase 1 used standard S-band antennas with the Tracking and Data Relay Satellite System to obtain a baseline performance. The selection process and available resources for Phase 2 resulted in a Ku-band phased array antenna system. Several development efforts are under way for a Ka-band phased array antenna system for Phase 3. Each phase includes test flights to demonstrate performance and capabilities. Successful completion of this project will result in a set of communications requirements for the next generation of launch vehicles.

A MATLAB based Distributed Real-time Simulation of Lander-Orbiter-Earth Communication for Lunar Missions

NASA Astrophysics Data System (ADS)

Choudhury, Diptyajit; Angeloski, Aleksandar; Ziah, Haseeb; Buchholz, Hilmar; Landsman, Andre; Gupta, Amitava; Mitra, Tiyasa

Lunar explorations often involve use of a lunar lander , a rover [1],[2] and an orbiter which rotates around the moon with a fixed radius. The orbiters are usually lunar satellites orbiting along a polar orbit to ensure visibility with respect to the rover and the Earth Station although with varying latency. Communication in such deep space missions is usually done using a specialized protocol like Proximity-1[3]. MATLAB simulation of Proximity-1 have been attempted by some contemporary researchers[4] to simulate all features like transmission control, delay etc. In this paper it is attempted to simulate, in real time, the communication between a tracking station on earth (earth station), a lunar orbiter and a lunar rover using concepts of Distributed Real-time Simulation(DRTS).The objective of the simulation is to simulate, in real-time, the time varying communication delays associated with the communicating elements with a facility to integrate specific simulation modules to study different aspects e.g. response due to a specific control command from the earth station to be executed by the rover. The hardware platform comprises four single board computers operating as stand-alone real time systems (developed by MATLAB xPC target and inter-networked using UDP-IP protocol). A time triggered DRTS approach is adopted. The earth station, the orbiter and the rover are programmed as three standalone real-time processes representing the communicating elements in the system. Communication from one communicating element to another constitutes an event which passes a state message from one element to another, augmenting the state of the latter. These events are handled by an event scheduler which is the fourth real-time process. The event scheduler simulates the delay in space communication taking into consideration the distance between the communicating elements. A unique time synchronization algorithm is developed which takes into account the large latencies in space communication. The DRTS setup thus developed serves as an important and inexpensive test bench for trying out remote controlled applications on the rover, for example, from an earth station. The simulation is modular and the system is composable. Each of the processes can be aug-mented with relevant simulation modules that handle the events to simulate specific function-alities. With stringent energy saving requirements on most rovers, such a simulation set up, for example, can be used to design optimal rover movement control strategies from the orbiter in conjunction with autonomous systems on the rover itself. References 1. Lunar and Planetary Department, Moscow University, Lunokhod 1, "http://selena.sai.msu.ru/Home/Spa 2. NASA History Office, Guidelines for Advanced Manned Space Vehicle Program, "http://history.nasa.gov 35ann/AMSVPguidelines/top.htm" 3. Consultative Committee For Space Data Systems, "Proximity-1 Space Link Protocol" CCSDS 211.0-B-1 Blue Book. October 2002. 4. Segui, J. and Jennings, E., "Delay Tolerant Networking-Bundle Protocol Simulation", in Proceedings of the 2nd IEEE International Conference on Space Mission Challenges for Infor-mation Technology, 2006.

Automated Planning for a Deep Space Communications Station

NASA Technical Reports Server (NTRS)

Estlin, Tara; Fisher, Forest; Mutz, Darren; Chien, Steve

1999-01-01

This paper describes the application of Artificial Intelligence planning techniques to the problem of antenna track plan generation for a NASA Deep Space Communications Station. Me described system enables an antenna communications station to automatically respond to a set of tracking goals by correctly configuring the appropriate hardware and software to provide the requested communication services. To perform this task, the Automated Scheduling and Planning Environment (ASPEN) has been applied to automatically produce antenna trucking plans that are tailored to support a set of input goals. In this paper, we describe the antenna automation problem, the ASPEN planning and scheduling system, how ASPEN is used to generate antenna track plans, the results of several technology demonstrations, and future work utilizing dynamic planning technology.

Crew and Thermal Systems Strategic Communications Initiatives in Support of NASA's Strategic Goals

NASA Technical Reports Server (NTRS)

Paul, Heather L.; Lamberth, Erika Guillory; Jennings, Mallory A.

2012-01-01

NASA has defined strategic goals to invest in next-generation technologies and innovations, inspire students to become the future leaders of space exploration, and expand partnerships with industry and academia around the world. The Crew and Thermal Systems Division (CTSD) at the NASA Johnson Space Center actively supports these NASA initiatives. In July 2011, CTSD created a strategic communications team to communicate CTSD capabilities, technologies, and personnel to external technical audiences for business development and collaborative initiatives, and to students, educators, and the general public for education and public outreach efforts. This paper summarizes the CTSD Strategic Communications efforts and metrics through the first half of fiscal year 2012 with projections for end of fiscal year data.

Crew and Thermal Systems Strategic Communications Initiatives in Support of NASA's Strategic Goals

NASA Technical Reports Server (NTRS)

Paul, Heather L.

2012-01-01

NASA has defined strategic goals to invest in next-generation technologies and innovations, to inspire students to become the future leaders of space exploration, and to expand partnerships with industry and academia around the world. The Crew and Thermal Systems Division (CTSD) at the NASA Johnson Space Center actively supports these NASA initiatives. In July 2011, CTSD created a strategic communications team to communicate CTSD capabilities, technologies, and personnel to internal NASA and external technical audiences for business development and collaborative initiatives, and to students, educators, and the general public for education and public outreach efforts. This paper summarizes the CTSD Strategic Communications efforts and metrics through the first nine months of fiscal year 2012.

Research progress of free space coherent optical communication

NASA Astrophysics Data System (ADS)

Tan, Zhenkun; Ke, Xizheng

2018-02-01

This paper mainly introduces the research progress of free space coherent optical communication in Xi'an University of Technology. In recent years, the research on the outer modulation technology of the laser, free-space-to-fiber coupling technique, the design of transmitting and receiving optical antenna, adaptive optical technology with or without wave-front sensor, automatic polarization control technology, frequency stabilization technology, heterodyne detection technology and high speed signal processing technology. Based on the above related research, the digital signal modulation, transmission, detection and data recovery are realized by the heterodyne detection technology in the free space optical communication system, and finally the function of smooth viewing high-definition video is realized.

Architectural Options for a Future Deep Space Optical Communications Network

NASA Technical Reports Server (NTRS)

Edwards, B. L.; Benjamin, T.; Scozzafava, J.; Khatri, F.; Sharma, J.; Parvin, B.; Liebrecht, P. E.; Fitzgerald, R. J.

2004-01-01

This paper provides an overview of different options at Earth to provide Deep Space optical communication services. It is based mainly on work done for the Mars Laser Communications Demonstration (MLCD) Project, a joint project between NASA's Goddard Space Flight Center (GSFC), the Jet Propulsion Laboratory, California Institute of Technology (JPL), and the Massachusetts Institute of Technology Lincoln Laboratory (MIT/LL). It also reports preliminary conclusions from the Tracking and Data Relay Satellite System Continuation Study at GSFC. A lasercom flight terminal will be flown on the Mars Telecommunications Orbiter (MTO) to be launched by NASA in 2009, and will be the first high rate deep space demonstration of this revolutionary technology.

Architectural Methodology Report

NASA Technical Reports Server (NTRS)

Dhas, Chris

2000-01-01

The establishment of conventions between two communicating entities in the end systems is essential for communications. Examples of the kind of decisions that need to be made in establishing a protocol convention include the nature of the data representation, the for-mat and the speed of the date representation over the communications path, and the sequence of control messages (if any) which are sent. One of the main functions of a protocol is to establish a standard path between the communicating entities. This is necessary to create a virtual communications medium with certain desirable characteristics. In essence, it is the function of the protocol to transform the characteristics of the physical communications environment into a more useful virtual communications model. The final function of a protocol is to establish standard data elements for communications over the path; that is, the protocol serves to create a virtual data element for exchange. Other systems may be constructed in which the transferred element is a program or a job. Finally, there are special purpose applications in which the element to be transferred may be a complex structure such as all or part of a graphic display. NASA's Glenn Research Center (GRC) defines and develops advanced technology for high priority national needs in communications technologies for application to aeronautics and space. GRC tasked Computer Networks and Software Inc. (CNS) to describe the methodologies used in developing a protocol architecture for an in-space Internet node. The node would support NASA:s four mission areas: Earth Science; Space Science; Human Exploration and Development of Space (HEDS); Aerospace Technology. This report presents the methodology for developing the protocol architecture. The methodology addresses the architecture for a computer communications environment. It does not address an analog voice architecture.

The Information Science Experiment System - The computer for science experiments in space

NASA Technical Reports Server (NTRS)

Foudriat, Edwin C.; Husson, Charles

1989-01-01

The concept of the Information Science Experiment System (ISES), potential experiments, and system requirements are reviewed. The ISES is conceived as a computer resource in space whose aim is to assist computer, earth, and space science experiments, to develop and demonstrate new information processing concepts, and to provide an experiment base for developing new information technology for use in space systems. The discussion covers system hardware and architecture, operating system software, the user interface, and the ground communication link.

Advanced Learning Space as an Asset for Students with Disabilities

ERIC Educational Resources Information Center

Císarová, Klára; Lamr, Marián; Vitvarová, Jana

2015-01-01

The paper describes an e-learning system called Advanced Learning Space that was developed at the Technical University of Liberec. The system provides a personalized virtual work space and promotes communication among students and their teachers. The core of the system is a module that can be used to automatically record, store and playback…

Research and technology

NASA Technical Reports Server (NTRS)

1986-01-01

Activities of the Goddard Space Flight Center are described in the areas of planets and interplanetary media, comets, astronomy and high-energy physics, solar physics, atmospheres, terrestrial physics, ocean science, sensors and space technology, techniques, user space data systems, space communications and navigation, and system and software engineering. Flight projects and mission definition studies are presented, and institutional technology is described.

Adaptive Suppression of Noise in Voice Communications

NASA Technical Reports Server (NTRS)

Kozel, David; DeVault, James A.; Birr, Richard B.

2003-01-01

A subsystem for the adaptive suppression of noise in a voice communication system effects a high level of reduction of noise that enters the system through microphones. The subsystem includes a digital signal processor (DSP) plus circuitry that implements voice-recognition and spectral- manipulation techniques. The development of the adaptive noise-suppression subsystem was prompted by the following considerations: During processing of the space shuttle at Kennedy Space Center, voice communications among test team members have been significantly impaired in several instances because some test participants have had to communicate from locations with high ambient noise levels. Ear protection for the personnel involved is commercially available and is used in such situations. However, commercially available noise-canceling microphones do not provide sufficient reduction of noise that enters through microphones and thus becomes transmitted on outbound communication links.

Differential phase-shift keying and channel equalization in free space optical communication system

NASA Astrophysics Data System (ADS)

Zhang, Dai; Hao, Shiqi; Zhao, Qingsong; Wan, Xiongfeng; Xu, Chenlu

2018-01-01

We present the performance benefits of differential phase-shift keying (DPSK) modulation in eliminating influence from atmospheric turbulence, especially for coherent free space optical (FSO) communication with a high communication rate. Analytic expression of detected signal is derived, based on which, homodyne detection efficiency is calculated to indicate the performance of wavefront compensation. Considered laser pulses always suffer from atmospheric scattering effect by clouds, intersymbol interference (ISI) in high-speed FSO communication link is analyzed. Correspondingly, the channel equalization method of a binormalized modified constant modulus algorithm based on set-membership filtering (SM-BNMCMA) is proposed to solve the ISI problem. Finally, through the comparison with existing channel equalization methods, its performance benefits of both ISI elimination and convergence speed are verified. The research findings have theoretical significance in a high-speed FSO communication system.

Heterogeneous Spacecraft Networks

NASA Technical Reports Server (NTRS)

Nakamura, Yosuke (Inventor); Faber, Nicolas T. (Inventor); Frost, Chad R. (Inventor); Alena, Richard L. (Inventor)

2018-01-01

The present invention provides a heterogeneous spacecraft network including a network management architecture to facilitate communication between a plurality of operations centers and a plurality of data user communities. The network management architecture includes a plurality of network nodes in communication with the plurality of operations centers. The present invention also provides a method of communication for a heterogeneous spacecraft network. The method includes: transmitting data from a first space segment to a first ground segment; transmitting the data from the first ground segment to a network management architecture; transmitting data from a second space segment to a second ground segment, the second space and ground segments having incompatible communication systems with the first space and ground segments; transmitting the data from the second ground station to the network management architecture; and, transmitting data from the network management architecture to a plurality of data user communities.

Advanced 3-V semiconductor technology assessment. [space communications

NASA Technical Reports Server (NTRS)

Nowogrodzki, M.

1983-01-01

Against a background of an extensive survey of the present state of the art in the field of III-V semiconductors for operation at microwave frequencies (or gigabit rate speeds), likely requirements of future space communications systems are identified, competing technologies and physical device limitations are discussed, and difficulties in implementing emerging technologies are projected. On the basis of these analyses, specific research and development programs required for the development of future systems components are recommended.

Design of a Solar Sail Mission to Mars

NASA Technical Reports Server (NTRS)

Eastridge, Richard; Funston, Kerry; Okia, Aminat; Waldrop, Joan; Zimmerman, Christopher

1989-01-01

An evaluation of the design of the solar sail includes key areas such as structures, sail deployment, space environmental effects, materials, power systems, telemetry, communications, attitude control, thermal control, and trajectory analysis. Deployment and material constraints determine the basic structure of the sail, while the trajectory of the sail influences the choice of telemetry, communications, and attitude control systems. The thermal control system of the sail for the structures and electronics takes into account the effects of the space environment. Included also are a cost and weight estimate for the sail.

The TAVERNS emulator: An Ada simulation of the space station data communications network and software development environment

NASA Technical Reports Server (NTRS)

Howes, Norman R.

1986-01-01

The Space Station DMS (Data Management System) is the onboard component of the Space Station Information System (SSIS) that includes the computers, networks and software that support the various core and payload subsystems of the Space Station. TAVERNS (Test And Validation Environment for Remote Networked Systems) is a distributed approach for development and validation of application software for Space Station. The TAVERNS concept assumes that the different subsystems will be developed by different contractors who may be geographically separated. The TAVERNS Emulator is an Ada simulation of a TAVERNS on the ASD VAX. The software services described in the DMS Test Bed User's Manual are being emulated on the VAX together with simulations of some of the core subsystems and a simulation of the DCN. The TAVERNS Emulator will be accessible remotely from any VAX that can communicate with the ASD VAX.

UWB Technology and Applications on Space Exploration

NASA Technical Reports Server (NTRS)

Ngo, Phong; Phan, Chau; Gross, Julia; Dusl, John; Ni, Jianjun; Rafford, Melinda

2006-01-01

Ultra-wideband (UWB), also known as impulse or carrier-free radio technology, is one promising new technology. In February 2002, the Federal Communications Commission (FCC) approved the deployment of this technology. It is increasingly recognized that UWB technology holds great potential to provide significant benefits in many terrestrial and space applications such as precise positioning/tracking and high data rate mobile wireless communications. This talk presents an introduction to UWB technology and some applications on space exploration. UWB is characterized by several uniquely attractive features, such as low impact on other RF systems due to its extremely low power spectral densities, immunity to interference from narrow band RF systems due to its ultra-wide bandwidth, multipath immunity to fading due to ample multipath diversity, capable of precise positioning due to fine time resolution, capable of high data rate multi-channel performance. The related FCC regulations, IEEE standardization efforts and industry activities also will be addressed in this talk. For space applications, some projects currently under development at NASA Johnson Space Center will be introduced. These include the UWB integrated communication and tracking system for Lunar/Mars rover and astronauts, UWB-RFID ISS inventory tracking, and UWB-TDOA close-in high resolution tracking for potential applications on robonaut.

The Automated Conflict Resolution System (ACRS)

NASA Technical Reports Server (NTRS)

Kaplan, Ted; Musliner, Andrew; Wampler, David

1993-01-01

The Automated Conflict Resolution System (ACRS) is a mission-current scheduling aid that predicts periods of mutual interference when two or more orbiting spacecraft are scheduled to communicate with the same Tracking and Data Relay Satellite (TDRS) at the same time. The mutual interference predicted has the potential to degrade or prevent communications. Thus the ACRS system is a useful tool for aiding in the scheduling of Space Network (SN) communications.

The Automated Conflict Resolution System (ACRS)

NASA Astrophysics Data System (ADS)

Kaplan, Ted; Musliner, Andrew; Wampler, David

1993-11-01

The Automated Conflict Resolution System (ACRS) is a mission-current scheduling aid that predicts periods of mutual interference when two or more orbiting spacecraft are scheduled to communicate with the same Tracking and Data Relay Satellite (TDRS) at the same time. The mutual interference predicted has the potential to degrade or prevent communications. Thus the ACRS system is a useful tool for aiding in the scheduling of Space Network (SN) communications.

Spacecraft-level verification of the Van Allen Probes' RF communication system

NASA Astrophysics Data System (ADS)

Crowne, M. J.; Srinivasan, D.; Royster, D.; Weaver, G.; Matlin, D.; Mosavi, N.

This paper presents the verification process, lessons learned, and selected test results of the radio frequency (RF) communication system of the Van Allen Probes, formerly known as the Radiation Belt Storm Probes (RBSP). The Van Allen Probes mission is investigating the doughnut-shaped regions of space known as the Van Allen radiation belts where the Sun interacts with charged particles trapped in Earth's magnetic field. Understanding this dynamic area that surrounds our planet is important to improving our ability to design spacecraft and missions for reliability and astronaut safety. The Van Allen Probes mission features two nearly identical spacecraft designed, built, and operated by the Johns Hopkins University Applied Physics Laboratory (JHU/APL) for the National Aeronautics and Space Administration (NASA). The RF communication system features the JHU/APL Frontier Radio. The Frontier Radio is a software-defined radio (SDR) designed for spaceborne communications, navigation, radio science, and sensor applications. This mission marks the first spaceflight usage of the Frontier Radio. RF ground support equipment (RF GSE) was developed using a ground station receiver similar to what will be used in flight and whose capabilities provided clarity into RF system performance that was previously not obtained until compatibility testing with the ground segments. The Van Allen Probes underwent EMC, acoustic, vibration, and thermal vacuum testing at the environmental test facilities at APL. During this time the RF communication system was rigorously tested to ensure optimal performance, including system-level testing down to threshold power levels. Compatibility tests were performed with the JHU/APL Satellite Communication Facility (SCF), the Universal Space Network (USN), and the Tracking and Data Relay Satellite System (TDRSS). Successful completion of this program as described in this paper validated the design of the system and demonstrated that it will be able to me- t all of the Van Allen Probes's communications requirements with its intended ground segments.

Augmenting the SCaN Link Budget Tool with Validated Atmospheric Propagation

NASA Technical Reports Server (NTRS)

Steinkerchner, Leo; Welch, Bryan

2017-01-01

In any Earth-Space or Space-Earth communications link, atmospheric effects cause significant signal attenuation. In order to develop a communications system that is cost effective while meeting appropriate performance requirements, it is important to accurately predict these effects for the given link parameters. This project aimed to develop a Matlab(TradeMark) (The MathWorks, Inc.) program that could augment the existing Space Communications and Navigation (SCaN) Link Budget Tool with accurate predictions of atmospheric attenuation of both optical and radio-frequency signals according to the SCaN Optical Link Assessment Model Version 5 and the International Telecommunications Union, Radiocommunications Sector (ITU-R) atmospheric propagation loss model, respectively. When compared to data collected from the Advance Communications Technology Satellite (ACTS), the radio-frequency model predicted attenuation to within 1.3 dB of loss for 95 of measurements. Ultimately, this tool will be integrated into the SCaN Center for Engineering, Networks, Integration, and Communications (SCENIC) user interface in order to support analysis of existing SCaN systems and planning capabilities for future NASA missions.

A Simulation Base Investigation of High Latency Space Systems Operations

NASA Technical Reports Server (NTRS)

Li, Zu Qun; Crues, Edwin Z.; Bielski, Paul; Moore, Michael

2017-01-01

NASA's human space program has developed considerable experience with near Earth space operations. Although NASA has experience with deep space robotic missions, NASA has little substantive experience with human deep space operations. Even in the Apollo program, the missions lasted only a few weeks and the communication latencies were on the order of seconds. Human missions beyond the relatively close confines of the Earth-Moon system will involve missions with durations measured in months and communications latencies measured in minutes. To minimize crew risk and to maximize mission success, NASA needs to develop a better understanding of the implications of these types of mission durations and communication latencies on vehicle design, mission design and flight controller interaction with the crew. To begin to address these needs, NASA performed a study using a physics-based subsystem simulation to investigate the interactions between spacecraft crew and a ground-based mission control center for vehicle subsystem operations across long communication delays. The simulation, built with a subsystem modeling tool developed at NASA's Johnson Space Center, models the life support system of a Mars transit vehicle. The simulation contains models of the cabin atmosphere and pressure control system, electrical power system, drinking and waste water systems, internal and external thermal control systems, and crew metabolic functions. The simulation has three interfaces: 1) a real-time crew interface that can be use to monitor and control the vehicle subsystems; 2) a mission control center interface with data transport delays up to 15 minutes each way; 3) a real-time simulation test conductor interface that can be use to insert subsystem malfunctions and observe the interactions between the crew, ground, and simulated vehicle. The study was conducted at the 21st NASA Extreme Environment Mission Operations (NEEMO) mission between July 18th and Aug 3rd of year 2016. The NEEMO mission provides ideal conditions for this study with crew in the loop, an active control center, and real-time flow of high latency communications and data. NEEMO crew and ground support will work through procedures including activation of the transit vehicle power system, opening the hatch between the transit vehicle and a Mars ascent vehicle, transferring simulated crewmembers between vehicles, overcoming subsystem malfunctions, sending simulated crewmember on extra-vehicular activities, and other housekeeping activities. This study is enhancing the understanding of high latency operations and the advantages and disadvantages of different communication methods. It is also providing results that will help improve the design of simulation interfaces and inform the design of Mars transit vehicles.

How Does a Modern Field Artillery Cannon Battalion Operate in a Degraded, Denied, and Disrupted Space Operating Environment

DTIC Science & Technology

2017-06-09

reports, a potential solution to communication shortfalls was the use of high frequency (HF) Harris radios that possess complex encryption... communications , positioning, and navigation do not properly function, is known as a Degraded, Denied, Disrupted Space Operating Environment (D3SOE).7...battalion operates in a D3SOE. This was a very relevant question for a force increasingly reliant on frequency modulated (FM) radio communication systems

Encryption protection for communication satellites

NASA Astrophysics Data System (ADS)

Sood, D. R.; Hoernig, O. W., Jr.

In connection with the growing importance of the commercial communication satellite systems and the introduction of new technological developments, users and operators of these systems become increasingly concerned with aspects of security. The user community is concerned with maintaining confidentiality and integrity of the information being transmitted over the satellite links, while the satellite operators are concerned about the safety of their assets in space. In response to these concerns, the commercial satellite operators are now taking steps to protect the communication information and the satellites. Thus, communication information is being protected by end-to-end encryption of the customer communication traffic. Attention is given to the selection of the NBS DES algorithm, the command protection systems, and the communication protection systems.

Systems engineering considerations for operational support systems

NASA Technical Reports Server (NTRS)

Aller, Robert O.

1993-01-01

Operations support as considered here is the infrastructure of people, procedures, facilities and systems that provide NASA with the capability to conduct space missions. This infrastructure involves most of the Centers but is concentrated principally at the Johnson Space Center, the Kennedy Space Center, the Goddard Space Flight Center, and the Jet Propulsion Laboratory. It includes mission training and planning, launch and recovery, mission control, tracking, communications, data retrieval and data processing.

Large space structures and systems in the space station era: A bibliography with indexes (supplement 03)

NASA Technical Reports Server (NTRS)

1991-01-01

Bibliographies and abstracts are listed for 1221 reports, articles, and other documents introduced into the NASA scientific and technical information system between January 1, 1991 and June 30, 1991. Topics covered include large space structures and systems, space stations, extravehicular activity, thermal environments and control, tethering, spacecraft power supplies, structural concepts and control systems, electronics, advanced materials, propulsion, policies and international cooperation, vibration and dynamic controls, robotics and remote operations, data and communication systems, electric power generation, space commercialization, orbital transfer, and human factors engineering.

Prediction of rain effects on earth-space communication links operating in the 10 to 35 GHz frequency range

NASA Technical Reports Server (NTRS)

Stutzman, Warren L.

1989-01-01

This paper reviews the effects of precipitation on earth-space communication links operating the 10 to 35 GHz frequency range. Emphasis is on the quantitative prediction of rain attenuation and depolarization. Discussions center on the models developed at Virginia Tech. Comments on other models are included as well as literature references to key works. Also included is the system level modeling for dual polarized communication systems with techniques for calculating antenna and propagation medium effects. Simple models for the calculation of average annual attenuation and cross-polarization discrimination (XPD) are presented. Calculation of worst month statistics are also presented.

TDRS-L Pre-Launch Press Conference

NASA Image and Video Library

2014-01-21

CAPE CANAVERAL, Fla. – During a news conference at NASA's Kennedy Space Center in Florida, agency and contractor officials discussed preparations for the launch of NASA's Tracking and Data Relay Satellite, or TDRS-L, spacecraft. Participants included Andy Kopito, Civil Space Programs director for Boeing Space & Intelligence Systems in El Segundo, Calif. The TDRS-L spacecraft is the second of three new satellites designed to ensure vital operational continuity for NASA by expanding the lifespan of the Tracking and Data Relay Satellite System TDRSS fleet, which consists of eight satellites in geosynchronous orbit. The spacecraft provide tracking, telemetry, command and high bandwidth data return services for numerous science and human exploration missions orbiting Earth. These include NASA's Hubble Space Telescope and the International Space Station. TDRS-L has a high-performance solar panel designed for more spacecraft power to meet the growing S-band communications requirements. TDRSS is one of NASA Space Communication and Navigation’s SCaN three networks providing space communications to NASA’s missions. For more information more about TDRS-L, visit: http://www.nasa.gov/tdrs To learn more about SCaN, visit: www.nasa.gov/scan Photo credit: NASA/Frankie Martin

Design Concepts for a Small Space-Based GEO Relay Satellite for Missions Between Low Earth and near Earth Orbits

NASA Technical Reports Server (NTRS)

Bhasin, Kul B.; Warner, Joseph D.; Oleson, Steven; Schier, James

2014-01-01

The main purpose of the Small Space-Based Geosynchronous Earth orbiting (GEO) satellite is to provide a space link to the user mission spacecraft for relaying data through ground networks to user Mission Control Centers. The Small Space Based Satellite (SSBS) will provide services comparable to those of a NASA Tracking Data Relay Satellite (TDRS) for the same type of links. The SSBS services will keep the user burden the same or lower than for TDRS and will support the same or higher data rates than those currently supported by TDRS. At present, TDRSS provides links and coverage below GEO; however, SSBS links and coverage capability to above GEO missions are being considered for the future, especially for Human Space Flight Missions (HSF). There is also a rising need for the capability to support high data rate links (exceeding 1 Gbps) for imaging applications. The communication payload on the SSBS will provide S/Ka-band single access links to the mission and a Ku-band link to the ground, with an optical communication payload as an option. To design the communication payload, various link budgets were analyzed and many possible operational scenarios examined. To reduce user burden, using a larger-sized antenna than is currently in use by TDRS was considered. Because of the SSBS design size, it was found that a SpaceX Falcon 9 rocket could deliver three SSBSs to GEO. This will greatly reduce the launch costs per satellite. Using electric propulsion was also evaluated versus using chemical propulsion; the power system size and time to orbit for various power systems were also considered. This paper will describe how the SSBS will meet future service requirements, concept of operations, and the design to meet NASA users' needs for below and above GEO missions. These users' needs not only address the observational mission requirements but also possible HSF missions to the year 2030. We will provide the trade-off analysis of the communication payload design in terms of the number of links looking above and below GEO; the detailed design of a GEO SSBS spacecraft bus and its accommodation of the communication payload, and a summary of the trade study that resulted in the selection of the Falcon 9 launch vehicle to deploy the SSBS and its impact on cost reductions per satellite. ======================================================================== Several initiatives have taken place within NASA1 and international space agencies2 to create a human exploration strategy for expanding human presence into the solar system; these initiatives have been driven by multiple factors to benefit Earth. Of the many elements in the strategy one stands out: to send robotic and human missions to destinations beyond Low Earth Orbit (LEO), including cis-lunar space, Near-Earth Asteroids (NEAs), the Moon, and Mars and its moons.3, 4 The time frame for human exploration to various destinations, based on the public information available,1,4 is shown in Figure 1. Advance planning is needed to define how future space communications services will be provided in the new budget environment to meet future space communications needs. The spacecraft for these missions can be dispersed anywhere from below LEO to beyond GEO, and to various destinations within the solar system. NASA's Space Communications and Navigation (SCaN) program office provides communication and tracking services to space missions during launch, in-orbit testing, and operation phases. Currently, SCaN's space networking relay satellites mainly provide services to users below GEO, at Near Earth Orbit (NEO), below LEO, and in deep space. The potential exists for using a space-based relay satellite, located in the vicinity of various solar system destinations, to provide communication space links to missions both below and above its orbit. Such relays can meet the needs of human exploration missions for maximum connectivity to Earth locations and for reduced latency. In the past, several studies assessed the ability of satellite-based relays working above GEO in conjunction with Earth ground stations. Many of these focused on the trade between space relay and direct-to-Earth station links5,6,7. Several others focused on top-level architecture based on relays at various destinations8,9,10,11,12. Much has changed in terms of microwave and optical technology since the publication of the referenced papers; Ka-band communication systems are being deployed, optical communication is being demonstrated, and spacecraft buses are becoming increasingly more functional and operational. A design concept study was undertaken to access the potential for deploying a Small Space-Based Satellite (SSBS) relay capable of serving missions between LEO and NEO. The needs of future human exploration missions were analyzed, and a notional relay-based architecture concept was generated as shown in Fig. 1. Relay satellites in Earth through cis-Lunar orbits are normally located in stable orbits requiring low fuel consumption. Relay satellites for Mars orbit are normally selected based on the mission requirement and projected fuel consumption. Relay satellites have extreme commonalities of functions between them, differing only in the redundancy and frequencies used; therefore, the relay satellite in GEO was selected for further analysis since it will be the first step in achieving a relay-based architecture for human exploration missions (see Fig.Figure 2). The mission design methodology developed by the Collaborative Modeling for Parametric Assessment of Space Systems (COMPASS) team13 was used to produce the satellite relay design and to perform various design trades. At the start of the activity, the team was provided with the detailed concept of the notional architecture and the system and communication payload drivers.

Space Shuttle Underside Astronaut Communications Performance Evaluation

NASA Technical Reports Server (NTRS)

Hwu, Shian U.; Dobbins, Justin A.; Loh, Yin-Chung; Kroll, Quin D.; Sham, Catherine C.

2005-01-01

The Space Shuttle Ultra High Frequency (UHF) communications system is planned to provide Radio Frequency (RF) coverage for astronauts working underside of the Space Shuttle Orbiter (SSO) for thermal tile inspection and repairing. This study is to assess the Space Shuttle UHF communication performance for astronauts in the shadow region without line-of-sight (LOS) to the Space Shuttle and Space Station UHF antennas. To insure the RF coverage performance at anticipated astronaut worksites, the link margin between the UHF antennas and Extravehicular Activity (EVA) Astronauts with significant vehicle structure blockage was analyzed. A series of near-field measurements were performed using the NASA/JSC Anechoic Chamber Antenna test facilities. Computational investigations were also performed using the electromagnetic modeling techniques. The computer simulation tool based on the Geometrical Theory of Diffraction (GTD) was used to compute the signal strengths. The signal strength was obtained by computing the reflected and diffracted fields along the propagation paths between the transmitting and receiving antennas. Based on the results obtained in this study, RF coverage for UHF communication links was determined for the anticipated astronaut worksite in the shadow region underneath the Space Shuttle.

The Capacity Gain of Orbital Angular Momentum Based Multiple-Input-Multiple-Output System

PubMed Central

Zhang, Zhuofan; Zheng, Shilie; Chen, Yiling; Jin, Xiaofeng; Chi, Hao; Zhang, Xianmin

2016-01-01

Wireless communication using electromagnetic wave carrying orbital angular momentum (OAM) has attracted increasing interest in recent years, and its potential to increase channel capacity has been explored widely. In this paper, we compare the technique of using uniform linear array consist of circular traveling-wave OAM antennas for multiplexing with the conventional multiple-in-multiple-out (MIMO) communication method, and numerical results show that the OAM based MIMO system can increase channel capacity while communication distance is long enough. An equivalent model is proposed to illustrate that the OAM multiplexing system is equivalent to a conventional MIMO system with a larger element spacing, which means OAM waves could decrease the spatial correlation of MIMO channel. In addition, the effects of some system parameters, such as OAM state interval and element spacing, on the capacity advantage of OAM based MIMO are also investigated. Our results reveal that OAM waves are complementary with MIMO method. OAM waves multiplexing is suitable for long-distance line-of-sight (LoS) communications or communications in open area where the multi-path effect is weak and can be used in massive MIMO systems as well. PMID:27146453

NASA's Advanced Communications Technology Satellite (ACTS)

NASA Technical Reports Server (NTRS)

Gedney, R. T.

1983-01-01

NASA recently restructured its Space Communications Program to emphasize the development of high risk communication technology useable in multiple frequency bands and to support a wide range of future communication needs. As part of this restructuring, the Advanced Communications Technology Satellite (ACTS) Project will develop and experimentally verify the technology associated with multiple fixed and scanning beam systems which will enable growth in communication satellite capacities and more effective utilization of the radio frequency spectrum. The ACTS requirements and operations as well as the technology significance for future systems are described.

Mitigating Aviation Communication and Satellite Orbit Operations Surprises from Adverse Space Weather

NASA Technical Reports Server (NTRS)

Tobiska, W. Kent

2008-01-01

Adverse space weather affects operational activities in aviation and satellite systems. For example, large solar flares create highly variable enhanced neutral atmosphere and ionosphere electron density regions. These regions impact aviation communication frequencies as well as precision orbit determination. The natural space environment, with its dynamic space weather variability, is additionally changed by human activity. The increase in orbital debris in low Earth orbit (LEO), combined with lower atmosphere CO2 that rises into the lower thermosphere and causes increased cooling that results in increased debris lifetime, adds to the environmental hazards of navigating in near-Earth space. This is at a time when commercial space endeavors are posed to begin more missions to LEO during the rise of the solar activity cycle toward the next maximum (2012). For satellite and aviation operators, adverse space weather results in greater expenses for orbit management, more communication outages or aviation and ground-based high frequency radio used, and an inability to effectively plan missions or service customers with space-based communication, imagery, and data transferal during time-critical activities. Examples of some revenue-impacting conditions and solutions for mitigating adverse space weather are offered.

Simultaneous data communication and position sensing with an impact ionization engineered avalanche photodiode array for free space optical communication

NASA Astrophysics Data System (ADS)

Ferraro, Mike S.; Mahon, Rita; Rabinovich, William S.; Murphy, James L.; Dexter, James L.; Clark, William R.; Waters, William D.; Vaccaro, Kenneth; Krejca, Brian D.

2017-02-01

Photodetectors in free space optical communication systems perform two functions: reception of data communication signals and position sensing for pointing, tracking, and stabilization. Traditionally, the optical receive path in an FSO system is split into separate paths for data detection and position sensing. The need for separate paths is a consequence of conflicting performance criteria between position sensitive detectors (PSD) and data detectors. Combining the functionality of both detector types requires that the combinational sensor not only have the bandwidth to support high data rate communication but the active area and spatial discrimination to accommodate position sensing. In this paper we present a large area, concentric five element impact ionization engineered avalanche photodiode array rated for bandwidths beyond 1GHz with a measured carrier ionization ratio of less than 0.1 at moderate APD gains. The integration of this array as a combinational sensor in an FSO system is discussed along with the development of a pointing and stabilization algorithm.

Development of Operational Free-Space-Optical (FSO) Laser Communication Systems Final Report CRADA No. TC02093.0

DOE Office of Scientific and Technical Information (OSTI.GOV)

Ruggiero, A.; Orgren, A.

This project was a collaborative effort between Lawrence Livermore National Security, LLC (formerly The Regents of the University of California)/Lawrence Livermore National Laboratory (LLNL) and LGS Innovations, LLC (formerly Lucent Technologies, Inc.), to develop long-range and mobile operational free-space optical (FSO) laser communication systems for specialized government applications. LLNL and LGS Innovations formerly Lucent Bell Laboratories Government Communications Systems performed this work for a United States Government (USG) Intelligence Work for Others (I-WFO) customer, also referred to as "Government Customer", or "Customer" and "Government Sponsor." The CRADA was a critical and required part of the LLNL technology transfer plan formore » the customer.« less

Hybrid routing technique for a fault-tolerant, integrated information network

NASA Technical Reports Server (NTRS)

Meredith, B. D.

1986-01-01

The evolutionary growth of the space station and the diverse activities onboard are expected to require a hierarchy of integrated, local area networks capable of supporting data, voice, and video communications. In addition, fault-tolerant network operation is necessary to protect communications between critical systems attached to the net and to relieve the valuable human resources onboard the space station of time-critical data system repair tasks. A key issue for the design of the fault-tolerant, integrated network is the development of a robust routing algorithm which dynamically selects the optimum communication paths through the net. A routing technique is described that adapts to topological changes in the network to support fault-tolerant operation and system evolvability.

Laser diode combining for free space optical communication

NASA Technical Reports Server (NTRS)

Mecherle, G. Stephen

1986-01-01

The maximization of photon delivery to a distant collector in free space optical communications systems calls for a laser diode-combining technique employing wavelength and/or polarization as the bases of its operation. Design considerations for such a combiner encompass high throughput efficiency, diffraction-limited angular divergence, and reasonable volume constraints. Combiners are presently found to require a generalized Strehl ratio concept which includes relative source misalignment; diffraction grating combiners may have a limited number of laser sources which can meet spectral requirements. Methods for the incorporation of a combiner into a communication system are compared. Power combining is concluded to be the best tradeoff of performance and complexity for all systems, except those that are severely limited by either background radiation or component bandwidth.

DSN test and training system

NASA Technical Reports Server (NTRS)

Thorman, H. C.

1975-01-01

Key characteristics of the Deep Space Network Test and Training System were presented. Completion of the Mark III-75 system implementation is reported. Plans are summarized for upgrading the system to a Mark III-77 configuration to support Deep Space Network preparations for the Mariner Jupiter/Saturn 1977 and Pioneer Venus 1978 missions. A general description of the Deep Space Station, Ground Communications Facility, and Network Operations Control Center functions that comprise the Deep Space Network Test and Training System is also presented.

Interfacing Space Communications and Navigation Network Simulation with Distributed System Integration Laboratories (DSIL)

NASA Technical Reports Server (NTRS)

Jennings, Esther H.; Nguyen, Sam P.; Wang, Shin-Ywan; Woo, Simon S.

2008-01-01

NASA's planned Lunar missions will involve multiple NASA centers where each participating center has a specific role and specialization. In this vision, the Constellation program (CxP)'s Distributed System Integration Laboratories (DSIL) architecture consist of multiple System Integration Labs (SILs), with simulators, emulators, testlabs and control centers interacting with each other over a broadband network to perform test and verification for mission scenarios. To support the end-to-end simulation and emulation effort of NASA' exploration initiatives, different NASA centers are interconnected to participate in distributed simulations. Currently, DSIL has interconnections among the following NASA centers: Johnson Space Center (JSC), Kennedy Space Center (KSC), Marshall Space Flight Center (MSFC) and Jet Propulsion Laboratory (JPL). Through interconnections and interactions among different NASA centers, critical resources and data can be shared, while independent simulations can be performed simultaneously at different NASA locations, to effectively utilize the simulation and emulation capabilities at each center. Furthermore, the development of DSIL can maximally leverage the existing project simulation and testing plans. In this work, we describe the specific role and development activities at JPL for Space Communications and Navigation Network (SCaN) simulator using the Multi-mission Advanced Communications Hybrid Environment for Test and Evaluation (MACHETE) tool to simulate communications effects among mission assets. Using MACHETE, different space network configurations among spacecrafts and ground systems of various parameter sets can be simulated. Data that is necessary for tracking, navigation, and guidance of spacecrafts such as Crew Exploration Vehicle (CEV), Crew Launch Vehicle (CLV), and Lunar Relay Satellite (LRS) and orbit calculation data are disseminated to different NASA centers and updated periodically using the High Level Architecture (HLA). In addition, the performance of DSIL under different traffic loads with different mix of data and priorities are evaluated.

Large space telescope, phase A. Volume 5: Support systems module

NASA Technical Reports Server (NTRS)

1972-01-01

The development and characteristics of the support systems module for the Large Space Telescope are discussed. The following systems and described: (1) thermal control, (2) electrical, (3) communication and data landing, (4) attitude control system, and (5) structural features. Analyses of maintainability and reliability considerations are included.

An Optimizing Space Data-Communications Scheduling Method and Algorithm with Interference Mitigation, Generalized for a Broad Class of Optimization Problems

NASA Technical Reports Server (NTRS)

Rash, James

2014-01-01

NASA's space data-communications infrastructure-the Space Network and the Ground Network-provide scheduled (as well as some limited types of unscheduled) data-communications services to user spacecraft. The Space Network operates several orbiting geostationary platforms (the Tracking and Data Relay Satellite System (TDRSS)), each with its own servicedelivery antennas onboard. The Ground Network operates service-delivery antennas at ground stations located around the world. Together, these networks enable data transfer between user spacecraft and their mission control centers on Earth. Scheduling data-communications events for spacecraft that use the NASA communications infrastructure-the relay satellites and the ground stations-can be accomplished today with software having an operational heritage dating from the 1980s or earlier. An implementation of the scheduling methods and algorithms disclosed and formally specified herein will produce globally optimized schedules with not only optimized service delivery by the space data-communications infrastructure but also optimized satisfaction of all user requirements and prescribed constraints, including radio frequency interference (RFI) constraints. Evolutionary algorithms, a class of probabilistic strategies for searching large solution spaces, is the essential technology invoked and exploited in this disclosure. Also disclosed are secondary methods and algorithms for optimizing the execution efficiency of the schedule-generation algorithms themselves. The scheduling methods and algorithms as presented are adaptable to accommodate the complexity of scheduling the civilian and/or military data-communications infrastructure within the expected range of future users and space- or ground-based service-delivery assets. Finally, the problem itself, and the methods and algorithms, are generalized and specified formally. The generalized methods and algorithms are applicable to a very broad class of combinatorial-optimization problems that encompasses, among many others, the problem of generating optimal space-data communications schedules.

Overview of Intelligent Power Controller Development for Human Deep Space Exploration

NASA Technical Reports Server (NTRS)

Soeder, James F.; Dever, Timothy P.; McNelis, Anne M.; Beach, Raymond F.; Trase, Larry M.; May, Ryan D.

2014-01-01

Intelligent or autonomous control of an entire spacecraft is a major technology that must be developed to enable NASA to meet its human exploration goals. NASA's current long term human space platform, the International Space Station, is in low Earth orbit with almost continuous communication with the ground based mission control. This permits the near real-time control by the ground of all of the core systems including power. As NASA moves beyond low Earth orbit, the issues of communication time-lag and lack of communication bandwidth beyond geosynchronous orbit does not permit this type of operation. This paper presents the work currently ongoing at NASA to develop an architecture for an autonomous power control system as well as the effort to assemble that controller into the framework of the vehicle mission manager and other subsystem controllers to enable autonomous control of the complete spacecraft. Due to the common problems faced in both space power systems and terrestrial power system, the potential for spin-off applications of this technology for use in micro-grids located at the edge or user end of terrestrial power grids for peak power accommodation and reliability are described.

Overview of Intelligent Power Controller Development for Human Deep Space Exploration

NASA Technical Reports Server (NTRS)

Soeder, James F.; Dever, Timothy P.; McNelis, Anne M.; Beach, Raymond F.; Trase, Larry M.; May, Ryan D.

2014-01-01

Intelligent or autonomous control of an entire spacecraft is a major technology that must be developed to enable NASA to meet its human exploration goals. NASA's current long term human space platform, the International Space Station, is in low earth orbit with almost continuous communication with the ground based mission control. This permits the near real-time control by the ground of all of the core systems including power. As NASA moves beyond Low Earth Orbit, the issues of communication time-lag and lack of communication bandwidth beyond geosynchronous orbit does not permit this type of operation. This paper presents the work currently ongoing at NASA to develop an architecture for an autonomous power control system as well as the effort to assemble that controller into the framework of the vehicle mission manager and other subsystem controllers to enable autonomous control of the complete spacecraft. Due to the common problems faced in both space power systems and terrestrial power system, the potential for spin-off applications of this technology for use in micro-grids located at the edge or user end of terrestrial power grids for peak power accommodation and reliability are described.

Overview of Intelligent Power Controller Development for Human Deep Space Exploration

NASA Technical Reports Server (NTRS)

Soeder, James F.; Dever, Timothy P.; McNelis, Anne M.; Beach, Raymond F.; Trase, Larry M.; May, Ryan

2014-01-01

Intelligent or autonomous control of an entire spacecraft is a major technology that must be developed to enable NASA to meet its human exploration goals. NASAs current long term human space platform, the International Space Station, is in low earth orbit with almost continuous communication with the ground based mission control. This permits the near real-time control by the ground of all of the core systems including power. As NASA moves beyond Low Earth Orbit, the issues of communication time-lag and lack of communication bandwidth beyond geosynchronous orbit does not permit this type of operation. This paper presents the work currently ongoing at NASA to develop an architecture for an autonomous power control system as well as the effort to assemble that controller into the framework of the vehicle mission manager and other subsystem controllers to enable autonomous control of the complete spacecraft. Due to the common problems faced in both space power systems and terrestrial power system, the potential for spin-off applications of this technology for use in micro-grids located at the edge or user end of terrestrial power grids for peak power accommodation and reliability are described.

Power efficient optical communications for space applications

NASA Technical Reports Server (NTRS)

Lesh, J. R.

1982-01-01

Optical communications technology promises substantial size, weight and power consumption savings for space to space high data rate communications over presently used microwave technology. These benefits are further increased by making the most efficient use of the available optical signal energy. This presentation will describe the progress to date on a project to design, build and demonstrate in the laboratory an optical communication system capable of conveying 2.5 bits of information per effective received photon. Such high power efficiencies will reduce the need for photon collection at the receiver and will greatly reduce the requirements for optical pointing accuracy, both at the transmitter as well as the receiver. A longer range program to demonstrate even higher photon efficiencies will also be described.

An Optimizing Space Data-Communications Scheduling Method and Algorithm with Interference Mitigation, Generalized for a Broad Class of Optimization Problems

NASA Technical Reports Server (NTRS)

Rash, James L.

2010-01-01

NASA's space data-communications infrastructure, the Space Network and the Ground Network, provide scheduled (as well as some limited types of unscheduled) data-communications services to user spacecraft via orbiting relay satellites and ground stations. An implementation of the methods and algorithms disclosed herein will be a system that produces globally optimized schedules with not only optimized service delivery by the space data-communications infrastructure but also optimized satisfaction of all user requirements and prescribed constraints, including radio frequency interference (RFI) constraints. Evolutionary search, a class of probabilistic strategies for searching large solution spaces, constitutes the essential technology in this disclosure. Also disclosed are methods and algorithms for optimizing the execution efficiency of the schedule-generation algorithm itself. The scheduling methods and algorithms as presented are adaptable to accommodate the complexity of scheduling the civilian and/or military data-communications infrastructure. Finally, the problem itself, and the methods and algorithms, are generalized and specified formally, with applicability to a very broad class of combinatorial optimization problems.

Communications and Intelligent Systems Division Overview

NASA Technical Reports Server (NTRS)

Emerson, Dawn

2017-01-01

Provides expertise, and plans, conducts and directs research and engineering development in the competency fields of advanced communications and intelligent systems technologies for applications in current and future aeronautics and space systems.Advances communication systems engineering, development and analysis needed for Glenn Research Center's leadership in communications and intelligent systems technology. Focus areas include advanced high frequency devices, components, and antennas; optical communications, health monitoring and instrumentation; digital signal processing for communications and navigation, and cognitive radios; network architectures, protocols, standards and network-based applications; intelligent controls, dynamics and diagnostics; and smart micro- and nano-sensors and harsh environment electronics. Research and discipline engineering allow for the creation of innovative concepts and designs for aerospace communication systems with reduced size and weight, increased functionality and intelligence. Performs proof-of-concept studies and analyses to assess the impact of the new technologies.

Reconfigurable, Intelligently-Adaptive, Communication System, an SDR Platform

NASA Technical Reports Server (NTRS)

Roche, Rigoberto

2016-01-01

The Space Telecommunications Radio System (STRS) provides a common, consistent framework to abstract the application software from the radio platform hardware. STRS aims to reduce the cost and risk of using complex, configurable and reprogrammable radio systems across NASA missions. The Glenn Research Center (GRC) team made a software-defined radio (SDR) platform STRS compliant by adding an STRS operating environment and a field programmable gate array (FPGA) wrapper, capable of implementing each of the platforms interfaces, as well as a test waveform to exercise those interfaces. This effort serves to provide a framework toward waveform development on an STRS compliant platform to support future space communication systems for advanced exploration missions. Validated STRS compliant applications provided tested code with extensive documentation to potentially reduce risk, cost and efforts in development of space-deployable SDRs. This paper discusses the advantages of STRS, the integration of STRS onto a Reconfigurable, Intelligently-Adaptive, Communication System (RIACS) SDR platform, the sample waveform, and wrapper development efforts. The paper emphasizes the infusion of the STRS Architecture onto the RIACS platform for potential use in next generation SDRs for advance exploration missions.

Qualification testing of fiber-based laser transmitters and on-orbit validation of a commercial laser system

NASA Astrophysics Data System (ADS)

Wright, M. W.; Wilkerson, M. W.; Tang, R. R.

2017-11-01

Qualification testing of fiber based laser transmitters is required for NASA's Deep Space Optical Communications program to mature the technology for space applications. In the absence of fully space qualified systems, commercial systems have been investigated in order to demonstrate the robustness of the technology. To this end, a 2.5 W fiber based laser source was developed as the transmitter for an optical communications experiment flown aboard the ISS as a part of a technology demonstration mission. The low cost system leveraged Mil Standard design principles and Telcordia certified components to the extent possible and was operated in a pressure vessel with active cooling. The laser was capable of high rate modulation but was limited by the mission requirements to 50 Mbps for downlinking stored video from the OPALS payload, externally mounted on the ISS. Environmental testing and space qualification of this unit will be discussed along with plans for a fully space qualified laser transmitter.

MEMS-Based Communications Systems for Space-Based Applications

NASA Technical Reports Server (NTRS)

DeLosSantos, Hector J.; Brunner, Robert A.; Lam, Juan F.; Hackett, Le Roy H.; Lohr, Ross F., Jr.; Larson, Lawrence E.; Loo, Robert Y.; Matloubian, Mehran; Tangonan, Gregory L.

1995-01-01

As user demand for higher capacity and flexibility in communications satellites increases, new ways to cope with the inherent limitations posed by the prohibitive mass and power consumption, needed to satisfy those requirements, are under investigation. Recent studies suggest that while new satellite architectures are necessary to enable multi-user, multi-data rate, multi-location satellite links, these new architectures will inevitably increase power consumption, and in turn, spacecraft mass, to such an extent that their successful implementation will demand novel lightweight/low power hardware approaches. In this paper, following a brief introduction to the fundamentals of communications satellites, we address the impact of micro-electro-mechanical systems (MEMS) technology, in particular micro-electro-mechanical (MEM) switches to mitigate the above mentioned problems and show that low-loss/wide bandwidth MEM switches will go a long way towards enabling higher capacity and flexibility space-based communications systems.

The 'locus' of health oversight in Brazil's Unified Health System - a place between the knowledge and the practices of social mobilization.

PubMed

Fernandes, Valcler Rangel; Luz, Zélia Profeta da; Amorim, Annibal Coelho de; Sérgio, Juraci Vieira; Silva, José Paulo Vicente da; Castro, Marcia Correa E; Monken, Maurício; Gondim, Grácia Maria de Miranda

2017-10-01

Supervision of a health system presupposes keeping an attentive eye on the health situation of populations, so as to understand health, illness and healthcare as indissociable manifestations of human existence. Taking this point of view, this article examines health practices from the basis of some of their processes of communication. These are markedly professional-centered in their logic, with their emphasis on scientific, vertical and authoritarian discourse, predominantly in the spaces of the Unified Health System (SUS). In the territory, the process of communication is determinant. As a result of social interaction in daily life, the communication process reterritorializes the elements of the social totality: people, companies, institutions are re-dimensioned in the logic. It is a characteristic space for activities that aim for a more horizontal and democratic flow of communication.

A Strategy for Thailand's Space Technology Development: National Space Program (NSP)

NASA Astrophysics Data System (ADS)

Pimnoo, Ammarin; Purivigraipong, Somphop

2016-07-01

The Royal Thai Government has established the National Space Policy Committee (NSPC) with mandates for setting policy and strategy. The NSPC is considering plans and budget allocation for Thai space development. NSPC's goal is to promote the utilization of space technology in a manner that is congruent with the current situation and useful for the economy, society, science, technology, educational development and national security. The first proposed initiative of the National Space Program (NSP) is co-development of THEOS-2, a next-generation satellite system that includes Thailand's second and third earth observation satellite (THAICHOTE-2 and THAICHOTE-3). THEOS-1 or THAICHOTE-1 was the first Earth Observation Satellite of Thailand launched in 2008. At present, the THAICHOTE-1 is over the lifetime, therefore the THEOS-2 project has been established. THEOS-2 is a complete Earth Observation System comprising THAICHOTE-2&3 as well as ground control segment and capacity building. Thus, NSPC has considered that Thailand should manage the space system. Geo-Informatics and Space Technology Development Agency (GISTDA) has been assigned to propose the initiative National Space Program (NSP). This paper describes the strategy of Thailand's National Space Program (NSP) which will be driven by GISTDA. First, NSP focuses on different aspects of the utilization of space on the basis of technology, innovation, knowledge and manpower. It contains driving mechanisms related to policy, implementation and use in order to promote further development. The Program aims to increase economic competitiveness, reduce social disparity, and improve social security, natural resource management and environmental sustainability. The NSP conceptual framework includes five aspects: communications satellites, earth observation satellite systems, space economy, space exploration and research, and NSP administration. THEOS-2 is considered a part of NSP with relevance to the earth observation satellite systems and space economy components. We also discuss the cooperative framework among space organizations or countries who are APRSAF members, with relevance to space exploration and research. The aspect of communications satellites may involve collaboration between Ministry of Science and Technology (MOST) and Ministry of Information and Communication Technology (ICT). In short, NSP is the first coherent and comprehensive effort covering all aspects of Thailand's space technology.

Communications system using a mirror kept in outer space by electromagnetic radiation pressure

DOEpatents

Csonka, Paul L.

1981-01-01

A method and system are described for transmitting electromagnetic radiation by using a communications mirror located between about 100 kilometers and about 200 kilometers above ground. The communications mirror is kept aloft above the atmosphere by the pressure of the electromagnetic radiation which it reflects, and which is beamed at the communications mirror by a suitably constructed transmitting antenna on the ground. The communications mirror will reflect communications, such as radio, radar, or television waves up to about 1,100 kilometers away when the communications mirror is located at a height of about 100 kilometers.

MILCOM '85 - Military Communications Conference, Boston, MA, October 20-23, 1985, Conference Record. Volumes 1, 2, & 3

NASA Astrophysics Data System (ADS)

The present conference on the development status of communications systems in the context of electronic warfare gives attention to topics in spread spectrum code acquisition, digital speech technology, fiber-optics communications, free space optical communications, the networking of HF systems, and applications and evaluation methods for digital speech. Also treated are issues in local area network system design, coding techniques and applications, technology applications for HF systems, receiver technologies, software development status, channel simultion/prediction methods, C3 networking spread spectrum networks, the improvement of communication efficiency and reliability through technical control methods, mobile radio systems, and adaptive antenna arrays. Finally, communications system cost analyses, spread spectrum performance, voice and image coding, switched networks, and microwave GaAs ICs, are considered.

The Telecommunications and Data Acquisition Report

NASA Technical Reports Server (NTRS)

Yuen, Joseph H. (Editor)

1994-01-01

This quarterly publication provides archival reports on developments in programs managed by JPL's Telecommunications and Mission Operations Directorate (TMOD), which now includes the former Telecommunications and Data Acquisition (TDA) Office. In space communications, radio navigation, radio science, and ground-based radio and radar astronomy, it reports on activities of the Deep Space Network (DS) in planning, supporting research and technology, implementation, and operations. Also included are standards activity at JPL for space data and information systems and reimbursable DSN work performed for other space agencies through NASA. The preceding work is all performed for NASA's Office of Space Communications (OSC).

KSC-02pd1578

NASA Image and Video Library

2002-10-18

KENNEDY SPACE CENTER, FLA. - The TDRS-J spacecraft, enclosed in a container, is transported past the Vehicle Assembly Building on its way to the Spacecraft Assembly and Encapsulation Facility-2 (SAEF-2) for processing. The Tracking and Data Relay Satellite System is the primary source of space-to-ground voice, data and telemetry for the Space Shuttle. It also provides communications with the International Space Station and scientific spacecraft in low-earth orbit such as the Hubble Space Telescope, and launch support for some expendable vehicles. This new advanced series of satellites will extend the availability of TDRS communications services until approximately 2017.

The Telecommunications and Data Acquisition Report

NASA Technical Reports Server (NTRS)

Yuen, Joseph H. (Editor)

1995-01-01

This quarterly publication provides archival reports on developments in programs managed by JPL's Telecommunications and Mission Operations Directorate (TMOD), which now includes the former Telecommunications and Data Acquisition (TDA) Office. In space communications, radio navigation, radio science, and ground-based radio and radar astronomy, it reports on activities of the Deep Space Network (DSN) in planning, supporting research and technology, implementation, and operations. Also included are standards activity at JPL for space data and information systems and reimbursable DSN work performed for other space agencies through NASA. The preceding work is all performed for NASA's Office of Space Communications (OSC).

Research on application of several tracking detectors in APT system

NASA Astrophysics Data System (ADS)

Liu, Zhi

2005-01-01

APT system is the key technology in free space optical communication system, and acquisition and tracking detector is the key component in PAT system. There are several candidate detectors that can be used in PAT system, such as CCD, QAPD and CMOS Imager etc. The characteristics of these detectors are quite different, i.e., the structures and the working schemes. This paper gives thoroughly compare of the usage and working principle of CCD and CMOS imager, and discusses the key parameters like tracking error, noise analyses, power analyses etc. Conclusion is given at the end of this paper that CMOS imager is a good candidate detector for PAT system in free space optical communication system.

Assessment of DSN Communication Coverage for Space Missions to Potentially Hazardous Asteroids

NASA Technical Reports Server (NTRS)

Kegege, Obadiah; Bittner, David; Gati, Frank; Bhasin, Kul

2012-01-01

A communication coverage gap exists for Deep Space Network (DSN) antennas. This communication coverage gap is on the southern hemisphere, centered at approximate latitude of -47deg and longitude of -45deg. The area of this communication gap varies depending on the altitude from the Earth s surface. There are no current planetary space missions that fall within the DSN communication gap because planetary bodies in the Solar system lie near the ecliptic plane. However, some asteroids orbits are not confined to the ecliptic plane. In recent years, Potentially Hazardous Asteroids (PHAs) have passed within 100,000 km of the Earth. NASA s future space exploration goals include a manned mission to asteroids. It is important to ensure reliable and redundant communication coverage/capabilities for manned space missions to dangerous asteroids that make a sequence of close Earth encounters. In this paper, we will describe simulations performed to determine whether near-Earth objects (NEO) that have been classified as PHAs fall within the DSN communication coverage gap. In the study, we reviewed literature for a number of PHAs, generated binary ephemeris for selected PHAs using JPL s HORIZONS tool, and created their trajectories using Satellite Took Kit (STK). The results show that some of the PHAs fall within DSN communication coverage gap. This paper presents the simulation results and our analyses

The National Aeronautics and Space Administration (NASA) Tracking and Data Relay Satellite System (TDRSS) program Economic and programmatic, considerations

NASA Technical Reports Server (NTRS)

Aller, R. O.

1985-01-01

The Tracking and Data Relay Satellite System (TDRSS) represents the principal element of a new space-based tracking and communication network which will support NASA spaceflight missions in low earth orbit. In its complete configuration, the TDRSS network will include a space segment consisting of three highly specialized communication satellites in geosynchronous orbit, a ground segment consisting of an earth terminal, and associated data handling and control facilities. The TDRSS network has the objective to provide communication and data relay services between the earth-orbiting spacecraft and their ground-based mission control and data handling centers. The first TDRSS spacecraft has been now in service for two years. The present paper is concerned with the TDRSS experience from the perspective of the various programmatic and economic considerations which relate to the program.

Recent Efforts in Communications Research and Technology at the Glenn Research Center in Support of NASA's Mission

NASA Technical Reports Server (NTRS)

Miranda, Felix A.

2015-01-01

As it has done in the past, NASA is currently engaged in furthering the frontiers of space and planetary exploration. The effectiveness in gathering the desired science data in the amount and quality required to perform this pioneering work relies heavily on the communications capabilities of the spacecraft and space platforms being considered to enable future missions. Accordingly, the continuous improvement and development of radiofrequency and optical communications systems are fundamental to prevent communications to become the limiting factor for space explorations. This presentation will discuss some of the research and technology development efforts currently underway at the NASA Glenn Research Center in the radio frequency (RF) and Optical Communications. Examples of work conducted in-house and also in collaboration with academia, industry, and other government agencies (OGA) in areas such as antenna technology, power amplifiers, radio frequency (RF) wave propagation through Earths atmosphere, ultra-sensitive receivers, thin films ferroelectric-based tunable components, among others, will be presented. In addition, the role of these and other related RF technologies in enabling the NASA next generation space communications architecture will be also discussed.

Micromachined modulator arrays for use in free-space optical communication systems

NASA Astrophysics Data System (ADS)

Lewis, Keith L.; Ridley, Kevin D.; McNie, Mark E.; Smith, Gilbert W.; Scott, Andrew M.

2004-12-01

A summary is presented of some of the design criteria relevant to the realisation of silicon micromachined modulator arrays for use in free-space optical communication systems. Theoretical performance levels achievable are compared with values measured on experimental devices produced using a modified Multi-User MEMS Process (MUMPS). Devices capable of realising modulation rates in excess of 300 kHz are described and their optical characteristics compared with published data on devices based on multiple quantum well technology.

Average capacity optimization in free-space optical communication system over atmospheric turbulence channels with pointing errors.

PubMed

Liu, Chao; Yao, Yong; Sun, Yun Xu; Xiao, Jun Jun; Zhao, Xin Hui

2010-10-01

A model is proposed to study the average capacity optimization in free-space optical (FSO) channels, accounting for effects of atmospheric turbulence and pointing errors. For a given transmitter laser power, it is shown that both transmitter beam divergence angle and beam waist can be tuned to maximize the average capacity. Meanwhile, their optimum values strongly depend on the jitter and operation wavelength. These results can be helpful for designing FSO communication systems.

RATANA MEEKHAM, AN ELECTRICAL INTEGRATION TECHNICIAN FOR QUALIS CORP. OF HUNTSVILLE, ALABAMA, HELPS TEST AVIONICS -- COMPLEX VEHICLE SYSTEMS ENABLING NAVIGATION, COMMUNICATIONS AND OTHER FUNCTIONS CRITICAL TO HUMAN SPACEFLIGHT

NASA Image and Video Library

2015-01-08

RATANA MEEKHAM, AN ELECTRICAL INTEGRATION TECHNICIAN FOR QUALIS CORP. OF HUNTSVILLE, ALABAMA, HELPS TEST AVIONICS -- COMPLEX VEHICLE SYSTEMS ENABLING NAVIGATION, COMMUNICATIONS AND OTHER FUNCTIONS CRITICAL TO HUMAN SPACEFLIGHT -- FOR THE SPACE LAUNCH SYSTEM PROGRAM AT NASA’S MARSHALL SPACE FLIGHT CENTER IN HUNTSVILLE, ALABAMA. HER WORK SUPPORTS THE NASA ENGINEERING & SCIENCE SERVICES AND SKILLS AUGMENTATION CONTRACT LED BY JACOBS ENGINEERING OF HUNTSVILLE. MEEKHAM WORKS FULL-TIME AT MARSHALL WHILE FINISHING HER ASSOCIATE'S DEGREE IN MACHINE TOOL TECHNOLOGY AT CALHOUN COMMUNITY COLLEGE IN DECATUR, ALABAMA. THE SPACE LAUNCH SYSTEM, NASA’S NEXT HEAVY-LIFT LAUNCH VEHICLE, IS THE WORLD’S MOST POWERFUL ROCKET, SET TO FLY ITS FIRST UNCREWED LUNAR ORBITAL MISSION IN 2018. ITS FIRST.

Present and future free-space quantum key distribution

NASA Astrophysics Data System (ADS)

Nordholt, Jane E.; Hughes, Richard J.; Morgan, George L.; Peterson, C. Glen; Wipf, Christopher C.

2002-04-01

Free-space quantum key distribution (QKD), more popularly know as quantum cryptography, uses single-photon free-space optical communications to distribute the secret keys required for secure communications. At Los Alamos National Laboratory we have demonstrated a fully automated system that is capable of operations at any time of day over a horizontal range of several kilometers. This has proven the technology is capable of operation from a spacecraft to the ground, opening up the possibility of QKD between any group of users anywhere on Earth. This system, the prototyping of a new system for use on a spacecraft, and the techniques required for world-wide quantum key distribution will be described. The operational parameters and performance of a system designed to operate between low earth orbit (LEO) and the ground will also be discussed.

Maximizing the security of chaotic optical communications.

PubMed

Hou, T T; Yi, L L; Yang, X L; Ke, J X; Hu, Y; Yang, Q; Zhou, P; Hu, W S

2016-10-03

The practical application of chaotic optical communications has been limited by two aspects: the difficulty in concealing the time delay - a critical security parameter in feedback chaotic systems, and the difficulty of significantly enlarging the key space without complicating the implementation. Here we propose an architecture to break the above limits. By introducing a frequency-dependent group delay module with frequency tuning resolution of 1 MHz into the chaotic feedback loop, we demonstrate excellent time delay concealment effect, and an additional huge key space of 10⁴⁸ can be achieved at the same time. The effectiveness is proved by both numerical simulation and experiment. Besides, the proposed scheme is compatible with the existing commercial optical communication systems, thus pave the way for high-speed secure optical communications.

The deep space network, volume 6

NASA Technical Reports Server (NTRS)

1971-01-01

Progress on Deep Space Network (DSN) supporting research and technology is presented, together with advanced development and engineering, implementation, and DSN operations of flight projects. The DSN is described. Interplanetary and planetary flight projects and radio science experiments are discussed. Tracking and navigational accuracy analysis, communications systems and elements research, and supporting research are considered. Development of the ground communications and deep space instrumentation facilities is also presented. Network allocation schedules and angle tracking and test development are included.

An assessment of the status and trends in satellite communications 1986-2000: An information document prepared for the Communications Subcommittee of the Space Applications Advisory Committee

NASA Technical Reports Server (NTRS)

Poley, W. A.; Stevens, G. H.; Stevenson, S. M.; Lekan, J.; Arth, C. H.; Hollansworth, J. E.; Miller, E. F.

1986-01-01

This is a response to a Space Applications Advisory Committee (SAAC) request for information about the status and trends in satellite communications, to be used to support efforts to conceive and recommend long range goals for NASA communications activities. Included in this document are assessments of: (1) the outlook for satellite communications, including current applications, potential future applications, and impact of the changing environment such as optical fiber networks, the Integrated Services Digital Network (ISDN) standard, and the rapidly growing market for Very Small Aperture Terminals (VSAT); (2) the restrictions imposed by our limited spectrum resource; and (3) technology needs indicated by future trends. Potential future systems discussed include: large powerful satellites for providing personal communications; VSAT compatible satellites with onboard switching and having voice capability; large satellites which offer a pervasive T1 network service (primarily for video-phone); and large geostationary communications facilities which support common use by several carriers. Also, discussion is included of NASA particular needs and possible future systems. Based on the mentioned system concepts, specific technology recommendations are provided for the time frames of now - 1993, 1994 - 2000, and 2000 - 2010.

Obstacle evasion in free-space optical communications utilizing Airy beams.

PubMed

Zhu, Guoxuan; Wen, Yuanhui; Wu, Xiong; Chen, Yujie; Liu, Jie; Yu, Siyuan

2018-03-15

A high speed free-space optical communication system capable of self-bending signal transmission around line-of-sight obstacles is proposed and demonstrated. Airy beams are generated and controlled to achieve different propagating trajectories, and the signal transmission characteristics of these beams around the obstacle are investigated. Our results confirm that, by optimizing their ballistic trajectories, Airy beams are able to bypass obstacles with more signal energy and thus improve the communication performance compared with normal Gaussian beams.

Obstacle evasion in free-space optical communications utilizing Airy beams

NASA Astrophysics Data System (ADS)

Zhu, Guoxuan; Wen, Yuanhui; Wu, Xiong; Chen, Yujie; Liu, Jie; Yu, Siyuan

2018-03-01

A high speed free-space optical communication system capable of self-bending signal transmission around line-of-sight obstacles is proposed and demonstrated. Airy beams are generated and controlled to achieve different propagating trajectories, and the signal transmission characteristics of these beams around the obstacle are investigated. Our results confirm that, by optimising their ballistic trajectories, Airy beams are able to bypass obstacles with more signal energy and thus improve the communication performance compared with normal Gaussian beams.

A guide to onboard checkout. Volume 7: RF communications

NASA Technical Reports Server (NTRS)

1971-01-01

The radio frequency communications subsystem for a space station is considered, with respect to onboard checkout requirements. The subsystem comprises all equipment necessary for transmitting and receiving, tracking and ranging, command, multiple voice and television information, and broadband experiment data. The communications subsystem provides a radio frequency interface between the space station and ground stations, either directly or indirectly, through a data relay satellite system, independent free-flying experiment modules, and logistics vehicles. Reliability, maintenance, and failure analyses are discussed, and computer programming techniques are presented.

Aperture Averaging of Scintillation for Space-to-Ground Optical Communication Applications.

DTIC Science & Technology

1983-08-15

SCINTILLATION FOR SPACE-TO-GROUND OPTICAL COMUNICATION APPLICATIONS ........................ 5 REFERENCES...theoretical investigations necessary for the evaluation and applica- tion of scientific advances to now military space systems. Versatility and flexibility...systems. Expertise in the latest scientific developments is vital to the accomplishment of tasks related to these problems. The laboratories that con

Free-space laser communication technologies IV; Proceedings of the 4th Conference, Los Angeles, CA, Jan. 23, 24, 1992

NASA Technical Reports Server (NTRS)

Begley, David L. (Editor); Seery, Bernard D. (Editor)

1992-01-01

Papers included in this volume are grouped under topics of receivers; laser transmitters; components; system analysis, performance, and applications; and beam control (pointing, acquisition, and tracking). Papers are presented on an experimental determination of power penalty contributions in an optical Costas-type phase-locked loop receiver, a resonant laser receiver for free-space laser communications, a simple low-loss technique for frequency-locking lasers, direct phase modulation of laser diodes, and a silex beacon. Particular attention is given to experimental results on an optical array antenna for nonmechanical beam steering, a potassium Faraday anomalous dispersion optical filter, a 100-Mbps resonant cavity phase modulator for coherent optical communications, a numerical simulation of a 325-Mbit/s QPPM optical communication system, design options for an optical multiple-access data relay terminal, CCD-based optical tracking loop design trades, and an analysis of a spatial-tracking subsystem for optical communications.

Digital nonlinearity compensation in high-capacity optical communication systems considering signal spectral broadening effect.

PubMed

Xu, Tianhua; Karanov, Boris; Shevchenko, Nikita A; Lavery, Domaniç; Liga, Gabriele; Killey, Robert I; Bayvel, Polina

2017-10-11

Nyquist-spaced transmission and digital signal processing have proved effective in maximising the spectral efficiency and reach of optical communication systems. In these systems, Kerr nonlinearity determines the performance limits, and leads to spectral broadening of the signals propagating in the fibre. Although digital nonlinearity compensation was validated to be promising for mitigating Kerr nonlinearities, the impact of spectral broadening on nonlinearity compensation has never been quantified. In this paper, the performance of multi-channel digital back-propagation (MC-DBP) for compensating fibre nonlinearities in Nyquist-spaced optical communication systems is investigated, when the effect of signal spectral broadening is considered. It is found that accounting for the spectral broadening effect is crucial for achieving the best performance of DBP in both single-channel and multi-channel communication systems, independent of modulation formats used. For multi-channel systems, the degradation of DBP performance due to neglecting the spectral broadening effect in the compensation is more significant for outer channels. Our work also quantified the minimum bandwidths of optical receivers and signal processing devices to ensure the optimal compensation of deterministic nonlinear distortions.

Dual-Use Space Technology Transfer Conference and Exhibition. Volume 2

NASA Technical Reports Server (NTRS)

Krishen, Kumar (Compiler)

1994-01-01

This is the second volume of papers presented at the Dual-Use Space Technology Transfer Conference and Exhibition held at the Johnson Space Center February 1-3, 1994. Possible technology transfers covered during the conference were in the areas of information access; innovative microwave and optical applications; materials and structures; marketing and barriers; intelligent systems; human factors and habitation; communications and data systems; business process and technology transfer; software engineering; biotechnology and advanced bioinstrumentation; communications signal processing and analysis; medical care; applications derived from control center data systems; human performance evaluation; technology transfer methods; mathematics, modeling, and simulation; propulsion; software analysis and decision tools; systems/processes in human support technology; networks, control centers, and distributed systems; power; rapid development; perception and vision technologies; integrated vehicle health management; automation technologies; advanced avionics; and robotics technologies.

Performance improvement of coherent free-space optical communication with quadrature phase-shift keying modulation using digital phase estimation.

PubMed

Li, Xueliang; Geng, Tianwen; Ma, Shuang; Li, Yatian; Gao, Shijie; Wu, Zhiyong

2017-06-01

The performance of coherent free-space optical (CFSO) communication with phase modulation is limited by both phase fluctuations and intensity scintillations induced by atmospheric turbulence. To improve the system performance, one effective way is to use digital phase estimation. In this paper, a CFSO communication system with quadrature phase-shift keying modulation is studied. With consideration of the effects of log-normal amplitude fluctuations and Gauss phase fluctuations, a two-stage Mth power carrier phase estimation (CPE) scheme is proposed. The simulation results show that the phase noise can be suppressed greatly by this scheme, and the system symbol error rate performance with the two-stage Mth power CPE can be three orders lower than that of the single-stage Mth power CPE. Therefore, the two-stage CPE we proposed can contribute to the performance improvements of the CFSO communication system and has determinate guidance sense to its actual application.

Space Transportation Materials and Structures Technology Workshop. Volume 2; Proceedings

NASA Technical Reports Server (NTRS)

Cazier, Frank W., Jr. (Compiler); Gardner, James E. (Compiler)

1993-01-01

The Space Transportation Materials and Structures Technology Workshop was held on September 23-26, 1991, in Newport News, Virginia. The workshop, sponsored by the NASA Office of Space Flight and the NASA Office of Aeronautics and Space Technology, was held to provide a forum for communication within the space materials and structures technology developer and user communities. Workshop participants were organized into a Vehicle Technology Requirements session and three working panels: Materials and Structures Technologies for Vehicle Systems, Propulsion Systems, and Entry Systems.

Collaboration Between Government and Commercial Space Weather Information Providers

NASA Astrophysics Data System (ADS)

Intriligator, Devrie

2007-10-01

Many systems and situations require up-to-date space weather information. These include navigation systems in cars, boats, and commercial freight; the specific location information needed for construction and oil drilling; communications; airline navigation; avionic systems; and passengers and personnel on polar airline flights. Thus, as the world's industries become increasingly more reliant on satellite data and more vulnerable to space weather conditions, new collaborations will have to be formed between commercial providers of space weather information and the government scientists who monitor space weather.

47 CFR 25.273 - Duties regarding space communications transmissions.

Code of Federal Regulations, 2011 CFR

2011-10-01

... angles for proper illumination of a given transponder. (c) Space station licensees are responsible for.... Based on this information, space station licensees shall exchange among themselves general technical... any potential cases of unacceptable interference between their satellite systems. (d) Space stations...

47 CFR 25.273 - Duties regarding space communications transmissions.

Code of Federal Regulations, 2014 CFR

2014-10-01

... angles for proper illumination of a given transponder. (c) Space station licensees are responsible for.... Based on this information, space station licensees shall exchange among themselves general technical... any potential cases of unacceptable interference between their satellite systems. (d) Space stations...

47 CFR 25.273 - Duties regarding space communications transmissions.

Code of Federal Regulations, 2012 CFR

2012-10-01

... angles for proper illumination of a given transponder. (c) Space station licensees are responsible for.... Based on this information, space station licensees shall exchange among themselves general technical... any potential cases of unacceptable interference between their satellite systems. (d) Space stations...

47 CFR 25.273 - Duties regarding space communications transmissions.

Code of Federal Regulations, 2013 CFR

2013-10-01

... angles for proper illumination of a given transponder. (c) Space station licensees are responsible for.... Based on this information, space station licensees shall exchange among themselves general technical... any potential cases of unacceptable interference between their satellite systems. (d) Space stations...

SpaceWire Data Handling Demonstration System

NASA Astrophysics Data System (ADS)

Mills, S.; Parkes, S. M.; O'Gribin, N.

2007-08-01

The SpaceWire standard was published in 2003 with the aim of providing a standard for onboard communications, defining the physical and data link layers of an interconnection, in order to improve reusability, reliability and to reduce the cost of mission development. The many benefits which it provides mean that it has already been used in a number of missions, both in Europe and throughout the world. Recent work by the SpaceWire community has included the development of higher level protocols for SpaceWire, such as the Remote Memory Access Protocol (RMAP) which can be used for many purposes, including the configuration of SpaceWire devices. Although SpaceWire has become very popular, the various ways in which it can be used are still being discovered, as are the most efficient ways to use it. At the same time, some in the space industry are not even aware of SpaceWire's existence. This paper describes the SpaceWire Data Handling Demonstration System that has been developed by the University of Dundee. This system simulates an onboard data handling network based on SpaceWire. It uses RMAP for all communication, and so demonstrates how SpaceWire and standardised higher level protocols can be used onboard a spacecraft. The system is not only a good advert for those who are unfamiliar with the benefits of SpaceWire, it is also a useful tool for those using SpaceWire to test ideas.

The optical communication link outage probability in satellite formation flying

NASA Astrophysics Data System (ADS)

Arnon, Shlomi; Gill, Eberhard

2014-02-01

In recent years, several space systems consisting of multiple satellites flying in close formation have been proposed for various purposes such as interferometric synthetic aperture radar measurement (TerraSAR-X and the TanDEM-X), detecting extra-solar earth-like planets (Terrestrial Planet Finder-TPF and Darwin), and demonstrating distributed space systems (DARPA F6 project). Another important purpose, which is the concern of this paper, is for improving radio frequency communication to mobile terrestrial and maritime subscribers. In this case, radio frequency signals from several satellites coherently combine such that the received/transmit signal strength is increased proportionally with the number of satellites in the formation. This increase in signal strength allows to enhance the communication data rate and/or to reduce energy consumption and the antenna size of terrestrial mobile users' equipment. However, a coherent combination of signals without aligning the phases of the individual communication signals interrupts the communication and outage link between the satellites and the user. The accuracy of the phase estimation is a function of the inter-satellite laser ranging system performance. This paper derives an outage probability model of a coherent combination communication system as a function of the pointing vibration and jitter statistics of an inter-satellite laser ranging system tool. The coherent combination probability model, which could be used to improve the communication to mobile subscribers in air, sea and ground is the main importance of this work.

Virtual Mission Operations of Remote Sensors With Rapid Access To and From Space

NASA Technical Reports Server (NTRS)

Ivancic, William D.; Stewart, Dave; Walke, Jon; Dikeman, Larry; Sage, Steven; Miller, Eric; Northam, James; Jackson, Chris; Taylor, John; Lynch, Scott;

TESAT laser communication terminal performance results on 5.6Gbit coherent inter satellite and satellite to ground links

NASA Astrophysics Data System (ADS)

Gregory, M.; Heine, F.; Kämpfner, H.; Meyer, R.; Fields, R.; Lunde, C.

2017-11-01

The increasing demand on high speed communication networks has stimulated the development of optical free space data transmission during the last years. TESAT has developed a laser communication terminal (LCT) that fulfills the need of a power efficient system whose capability has been successfully demonstrated at bidirectional space-to-space links and bidirectional space-to-ground links (SGLs) at a data rate of 5.625 GBit/s with a homodyne detection scheme and a BPSK modulation format. In comparison to a direct detection system, the homodyne detection scheme works as a bandpass filter. The transmission is immune to false light and even data transmission with the sun in the receiver field of view (FOV) is possible. Compared to common RF transmission which is implemented on spacecrafts for data transmission, optical transmission provides not only higher transmission rates (factor 10) but also shows excellent security features since the laser beams directivity making it immune to interception.

Conceptual designs of onboard transceivers for ground-to-satellite quantum cryptography

NASA Astrophysics Data System (ADS)

Toyoshima, Morio; Shoji, Yozo; Takayama, Yoshihisa; Kunimori, Hiroo; Takeoka, Masahiro; Fujiwara, Mikio; Sasaki, Masahide

2009-05-01

A free-space quantum key distribution system is being developed by the National Institute of Information and Communications Technology (NICT) in Koganei, Japan. Quantum cryptography is a new technique for transmitting information where the security is guaranteed by the laws of physics. In such systems, a single photon is used for the quantum information. However, since the transmission distance in optical fibers is limited by the absorption of photons by the fiber, the maximum demonstrated range has been limited to about 100 km. Free-space quantum cryptography between an optical ground station and a satellite is a possible solution to extend the distance for a quantum network beyond the limits of optical fibers. At NICT, a laser communication demonstration between the NICT optical ground station and a low earth orbit satellite was successfully conducted in 2006. The use of free-space quantum key distribution for such space communication links is considered an important future application. This paper presents conceptual designs for the onboard transceivers for satellite quantum cryptography

Demonstration of a free-space optical communication system using a solar-pumped laser as signal transmitter

NASA Astrophysics Data System (ADS)

Guan, Z.; Zhao, C. M.; Yang, S. H.; Wang, Y.; Ke, J. Y.; Zhang, H. Y.

2017-05-01

A free-space optical communication system with a sun light directly pumped laser as the signal transmitter was demonstrated. A 0.6  ×  0.6 m Fresnel lens was used as the primary concentrator to collect the solar light. 6.8 W continuous wave laser power was obtained from a 4 mm diameter grooved Nd:YAG rod. The output intensity was modulated with a video signal via a LiNbO3 Mach-Zehnder optoelectronic modulator. The video signal with a resolution of 1920  *  1080/frame and the frame rate of 25 Hz was transmitted over five-meter free-space in real time with high fidelity. The transmission rate was 125 Mbps and bit error rate was lower than 10-6. This research shows the feasibility of applying a solar light directly pumped laser for free-space optical communication, which is significant for telecommunications between satellites.

The HAL 9000 Space Operating System Real-Time Planning Engine Design and Operations Requirements

NASA Technical Reports Server (NTRS)

Stetson, Howard; Watson, Michael D.; Shaughnessy, Ray

2012-01-01

In support of future deep space manned missions, an autonomous/automated vehicle, providing crew autonomy and an autonomous response planning system, will be required due to the light time delays in communication. Vehicle capabilities as a whole must provide for tactical response to vehicle system failures and space environmental effects induced failures, for risk mitigation of permanent loss of communication with Earth, and for assured crew return capabilities. The complexity of human rated space systems and the limited crew sizes and crew skills mix drive the need for a robust autonomous capability on-board the vehicle. The HAL 9000 Space Operating System[2] designed for such missions and space craft includes the first distributed real-time planning / re-planning system. This paper will detail the software architecture of the multiple planning engine system, and the interface design for plan changes, approval and implementation that is performed autonomously. Operations scenarios will be defined for analysis of the planning engines operations and its requirements for nominal / off nominal activities. An assessment of the distributed realtime re-planning system, in the defined operations environment, will be provided as well as findings as it pertains to the vehicle, crew, and mission control requirements needed for implementation.

The design and implementation of the Technical Facilities Controller (TFC) for the Goldstone deep space communications complex

NASA Technical Reports Server (NTRS)

Killian, D. A.; Menninger, F. J.; Gorman, T.; Glenn, P.

1988-01-01

The Technical Facilities Controller is a microprocessor-based energy management system that is to be implemented in the Deep Space Network facilities. This system is used in conjunction with facilities equipment at each of the complexes in the operation and maintenance of air-conditioning equipment, power generation equipment, power distribution equipment, and other primary facilities equipment. The implementation of the Technical Facilities Controller was completed at the Goldstone Deep Space Communications Complex and is now operational. The installation completed at the Goldstone Complex is described and the utilization of the Technical Facilities Controller is evaluated. The findings will be used in the decision to implement a similar system at the overseas complexes at Canberra, Australia, and Madrid, Spain.

Wideband 1.064 micrometer detector evaluation

NASA Technical Reports Server (NTRS)

Green, S. I.

1975-01-01

The performance of several candidate detectors for use as communications detectors in a 400 Mbps 1.064 micrometers laser communication system was evaluated. The results of communication system Bit Error Rate (BER) testing for the best detector of each type are summarized. Complete testing data of each type detector is presented. The 400 Mbps 1.064 micrometers communication system receiver test bed is described. The best communication system results for each detector type are included. Performance comparisons are made at 0.000001 BER, the specification level chosen for satellite laser communication links. The data is presented in two groups. The first indicates the best performance levels that can be expected on normal space laser communication system operation. The second cites the best performance levels which can be achieved by focusing the signal to diffraction limited spots on the photosensitive area.

Implementation of a Space Communications Cognitive Engine

NASA Technical Reports Server (NTRS)

Hackett, Timothy M.; Bilen, Sven G.; Ferreira, Paulo Victor R.; Wyglinski, Alexander M.; Reinhart, Richard C.

2017-01-01

Although communications-based cognitive engines have been proposed, very few have been implemented in a full system, especially in a space communications system. In this paper, we detail the implementation of a multi-objective reinforcement-learning algorithm and deep artificial neural networks for the use as a radio-resource-allocation controller. The modular software architecture presented encourages re-use and easy modification for trying different algorithms. Various trade studies involved with the system implementation and integration are discussed. These include the choice of software libraries that provide platform flexibility and promote reusability, choices regarding the deployment of this cognitive engine within a system architecture using the DVB-S2 standard and commercial hardware, and constraints placed on the cognitive engine caused by real-world radio constraints. The implemented radio-resource allocation-management controller was then integrated with the larger spaceground system developed by NASA Glenn Research Center (GRC).

Fighting in a Contested Space Environment: Training Marines for Operations with Degraded or Denied Space-Enabled Capabilities

DTIC Science & Technology

2015-06-01

System UFG Ulchi Freedom Guardian UFO UHF Follow-On System UHF Ultra-High Frequency URE User Range Error VTC Video Teleconference WGS Wideband...in the UHF band; two legacy systems, Fleet Satellite Communication System (FLTSATCOM) and UHF Follow-on ( UFO ), and the new constellation being

Level crossing statistics for optical beam wander in a turbulent atmosphere with applications to ground-to-space laser communications.

PubMed

Yura, Harold T; Fields, Renny A

2011-06-20

Level crossing statistics is applied to the complex problem of atmospheric turbulence-induced beam wander for laser propagation from ground to space. A comprehensive estimate of the single-axis wander angle temporal autocorrelation function and the corresponding power spectrum is used to develop, for the first time to our knowledge, analytic expressions for the mean angular level crossing rate and the mean duration of such crossings. These results are based on an extension and generalization of a previous seminal analysis of the beam wander variance by Klyatskin and Kon. In the geometrical optics limit, we obtain an expression for the beam wander variance that is valid for both an arbitrarily shaped initial beam profile and transmitting aperture. It is shown that beam wander can disrupt bidirectional ground-to-space laser communication systems whose small apertures do not require adaptive optics to deliver uniform beams at their intended target receivers in space. The magnitude and rate of beam wander is estimated for turbulence profiles enveloping some practical laser communication deployment options and suggesting what level of beam wander effects must be mitigated to demonstrate effective bidirectional laser communication systems.

Quick acquisition and recognition method for the beacon in deep space optical communications.

PubMed

Wang, Qiang; Liu, Yuefei; Ma, Jing; Tan, Liying; Yu, Siyuan; Li, Changjiang

2016-12-01

In deep space optical communications, it is very difficult to acquire the beacon given the long communication distance. Acquisition efficiency is essential for establishing and holding the optical communication link. Here we proposed a quick acquisition and recognition method for the beacon in deep optical communications based on the characteristics of the deep optical link. To identify the beacon from the background light efficiently, we utilized the maximum similarity between the collecting image and the reference image for accurate recognition and acquisition of the beacon in the area of uncertainty. First, the collecting image and the reference image were processed by Fourier-Mellin. Second, image sampling and image matching were applied for the accurate positioning of the beacon. Finally, the field programmable gate array (FPGA)-based system was used to verify and realize this method. The experimental results showed that the acquisition time for the beacon was as fast as 8.1s. Future application of this method in the system design of deep optical communication will be beneficial.

Secure Autonomous Automated Scheduling (SAAS). Rev. 1.1

NASA Technical Reports Server (NTRS)

Walke, Jon G.; Dikeman, Larry; Sage, Stephen P.; Miller, Eric M.

2010-01-01

This report describes network-centric operations, where a virtual mission operations center autonomously receives sensor triggers, and schedules space and ground assets using Internet-based technologies and service-oriented architectures. For proof-of-concept purposes, sensor triggers are received from the United States Geological Survey (USGS) to determine targets for space-based sensors. The Surrey Satellite Technology Limited (SSTL) Disaster Monitoring Constellation satellite, the UK-DMC, is used as the space-based sensor. The UK-DMC's availability is determined via machine-to-machine communications using SSTL's mission planning system. Access to/from the UK-DMC for tasking and sensor data is via SSTL's and Universal Space Network's (USN) ground assets. The availability and scheduling of USN's assets can also be performed autonomously via machine-to-machine communications. All communication, both on the ground and between ground and space, uses open Internet standards

Veggie System on International Space Station

NASA Image and Video Library

2017-04-03

Charles Spern, project manager on the Engineering Services Contract, communicates instructions for the Veggie system to astronaut Peggy Whitson aboard the International Space Station during the initiation of the second Chinese cabbage to be grown aboard the orbiting laboratory on April 3, 2017.

Performance analysis of a coherent free space optical communication system based on experiment.

PubMed

Cao, Jingtai; Zhao, Xiaohui; Liu, Wei; Gu, Haijun

2017-06-26

Based on our previous study and designed experimental AO system with a 97-element continuous surface deformable mirror, we conduct the performance analysis of a coherent free space optical communication (FSOC) system for mixing efficiency (ME), bit error rate (BER) and outage probability under different Greenwood frequency and atmospheric coherent length. The results show that the influence of the atmospheric temporal characteristics on the performance is slightly stronger than that of the spatial characteristics when the receiving aperture and the number of sub-apertures are given. This analysis result provides a reference for the design of the coherent FSOC system.

Programmable Pacemaker

NASA Technical Reports Server (NTRS)

1996-01-01

Released in 1995, the Trilogy cardiac pacemaker is the fourth generation of a unit developed in the 1970s by NASA, Johns Hopkins Applied Physics Laboratory and St. Jude Medical's Cardiac Rhythm Management Division (formerly known as Pacesetter Systems, Inc.). The new system incorporates the company's PDx diagnostic and programming software and a powerful microprocessor that allows more functions to be fully automatic and gives more detailed information on the patient's health and the performance of the pacing systems. The pacemaker incorporates bidirectional telemetry used for space communications for noninvasive communication with the implanted pacemaker, smaller implantable pulse generators from space microminiaturization, and longer-life batteries from technology for spacecraft electrical power systems.

The first and second generation Aussat systems

NASA Astrophysics Data System (ADS)

Hope, W.

1988-12-01

The present three-spacecraft Aussat satellite communication system is described and illustrated with extensive drawings, diagrams, and photographs; and plans for the second-generation system (Aussat-B, to begin replacing the current spacecraft in 1992) are discussed. Consideration is given to the legal status, structure, and staff of the Aussat organization; the first-generation space segment; satellite launch and orbital transfer procedures; the Aussat communication payload; the ground segment; and the current market for satellite services in Australia. For the second-generation system, topics addressed include additional and improved services, the Aussat-B procurement program, mobile satellite services, and the impact on the Australian space industry.

Influence of atmospheric turbulence on optical communications using orbital angular momentum for encoding.

PubMed

Malik, Mehul; O'Sullivan, Malcolm; Rodenburg, Brandon; Mirhosseini, Mohammad; Leach, Jonathan; Lavery, Martin P J; Padgett, Miles J; Boyd, Robert W

2012-06-04

We describe an experimental implementation of a free-space 11-dimensional communication system using orbital angular momentum (OAM) modes. This system has a maximum measured OAM channel capacity of 2.12 bits/photon. The effects of Kolmogorov thin-phase turbulence on the OAM channel capacity are quantified. We find that increasing the turbulence leads to a degradation of the channel capacity. We are able to mitigate the effects of turbulence by increasing the spacing between detected OAM modes. This study has implications for high-dimensional quantum key distribution (QKD) systems. We describe the sort of QKD system that could be built using our current technology.

Reconfigurable, Intelligently-Adaptive, Communication System, an SDR Platform

NASA Technical Reports Server (NTRS)

Roche, Rigoberto J.; Shalkhauser, Mary Jo; Hickey, Joseph P.; Briones, Janette C.

2016-01-01

The Space Telecommunications Radio System (STRS) provides a common, consistent framework to abstract the application software from the radio platform hardware. STRS aims to reduce the cost and risk of using complex, configurable and reprogrammable radio systems across NASA missions. The NASA Glenn Research Center (GRC) team made a software defined radio (SDR) platform STRS compliant by adding an STRS operating environment and a field programmable gate array (FPGA) wrapper, capable of implementing each of the platforms interfaces, as well as a test waveform to exercise those interfaces. This effort serves to provide a framework toward waveform development onto an STRS compliant platform to support future space communication systems for advanced exploration missions. The use of validated STRS compliant applications provides tested code with extensive documentation to potentially reduce risk, cost and e ort in development of space-deployable SDRs. This paper discusses the advantages of STRS, the integration of STRS onto a Reconfigurable, Intelligently-Adaptive, Communication System (RIACS) SDR platform, and the test waveform and wrapper development e orts. The paper emphasizes the infusion of the STRS Architecture onto the RIACS platform for potential use in next generation flight system SDRs for advanced exploration missions.

Communications system evolutionary scenarios for Martian SEI support

NASA Technical Reports Server (NTRS)

Kwong, Paulman W.; Bruno, Ronald C.

1992-01-01

In the Space Exploration Initiative (SEI) mission scenarios, expanding human presence is the primary driver for high data rate Mars-Earth communications. To support an expanding human presence, the data rate requirement will be gradual, following the phased implementation over time of the evolving SEI mission. Similarly, the growth and evolution of the space communications infrastructure to serve this requirement will also be gradual to efficiently exploit the useful life of the installed communications infrastructure and to ensure backward compatibility with long-term users. In work conducted over the past year, a number of alternatives for supporting high data rate Mars-Earth communications have been analyzed with respect to their compatibility with gradual evolution of the space communications infrastructure. The alternatives include RF, millimeter wave (MMW), and optical implementations, and incorporate both surface and space-based relay terminals in the Mars and Earth regions. Each alternative is evaluated with respect to its ability to efficiently meet a projected growth in data rate over time, its technology readiness, and its capability to satisfy the key conditions and constraints imposed by evolutionary transition. As a result of this analysis, a set of attractive alternative communications architectures have been identified and described, and a road map is developed that illustrates the most rational and beneficial evolutionary paths for the communications infrastructure.

Solar heating system installed at Telex Communications, Inc., Blue Earth, Minnesota

NASA Technical Reports Server (NTRS)

1977-01-01

The solar heating system for space heating a 97,000 square foot building which houses administrative offices, assembly areas, and warehouse space is summarized. Information on system description, test data, major problems and resolutions, performance, operation and maintenance manual, manufacturer's literature, and as-built drawings is presented.

Electromagnetic compatibility test report for the tethered satellite data acquisition and control assembly

NASA Astrophysics Data System (ADS)

Hoskins, Douglas; Snead, Robert

1988-05-01

This report details the results of an electromagnetic compatibility test on the SCI Systems Data Acquisition and Control Assembly (DACA). This assembly is an electronic processor which controls the central communication link from the Tethered Satellite System (TSS) to the Space Transportation System Orbiter Space Shuttle.

Initial Characterization of Optical Communications with Disruption-Tolerant Network Protocols

NASA Technical Reports Server (NTRS)

Schoolcraft, Joshua; Wilson, Keith

2011-01-01

Disruption-tolerant networks (DTNs) are groups of network assets connected with a suite of communication protocol technologies designed to mitigate the effects of link delay and disruption. Application of DTN protocols to diverse groups of network resources in multiple sub-networks results in an overlay network-of-networks with autonomous data routing capability. In space environments where delay or disruption is expected, performance of this type of architecture (such as an interplanetary internet) can increase with the inclusion of new communications mediums and techniques. Space-based optical communication links are therefore an excellent building block of space DTN architectures. When compared to traditional radio frequency (RF) communications, optical systems can provide extremely power-efficient and high bandwidth links bridging sub-networks. Because optical links are more susceptible to link disruption and experience the same light-speed delays as RF, optical-enabled DTN architectures can lessen potential drawbacks and maintain the benefits of autonomous optical communications over deep space distances. These environment-driven expectations - link delay and interruption, along with asymmetric data rates - are the purpose of the proof-of-concept experiment outlined herein. In recognizing the potential of these two technologies, we report an initial experiment and characterization of the performance of a DTN-enabled space optical link. The experiment design employs a point-to-point free-space optical link configured to have asymmetric bandwidth. This link connects two networked systems running a DTN protocol implementation designed and written at JPL for use on spacecraft, and further configured for higher bandwidth performance. Comparing baseline data transmission metrics with and without periodic optical link interruptions, the experiment confirmed the DTN protocols' ability to handle real-world unexpected link outages while maintaining capability of reliably delivering data at relatively high rates. Finally, performance characterizations from this data suggest performance optimizations to configuration and protocols for future optical-specific DTN space link scenarios.

Fade-resistant forward error correction method for free-space optical communications systems

DOEpatents

Johnson, Gary W.; Dowla, Farid U.; Ruggiero, Anthony J.

2007-10-02

Free-space optical (FSO) laser communication systems offer exceptionally wide-bandwidth, secure connections between platforms that cannot other wise be connected via physical means such as optical fiber or cable. However, FSO links are subject to strong channel fading due to atmospheric turbulence and beam pointing errors, limiting practical performance and reliability. We have developed a fade-tolerant architecture based on forward error correcting codes (FECs) combined with delayed, redundant, sub-channels. This redundancy is made feasible though dense wavelength division multiplexing (WDM) and/or high-order M-ary modulation. Experiments and simulations show that error-free communications is feasible even when faced with fades that are tens of milliseconds long. We describe plans for practical implementation of a complete system operating at 2.5 Gbps.

Intensity position modulation for free-space laser communication system

NASA Astrophysics Data System (ADS)

Jangjoo, Alireza; Faghihi, F.

2004-12-01

In this research a novel modulation technique for free-space laser communication system called Intensity Position Modulation (IPM) is carried out. According to TEM00 mode of a laser beam and by linear fitting on the Gaussian function as an approximation, the variation of linear part on the reverse biased pn photodiode produced alternating currents which contain the information. Here, no characteristic property of the beam as intensity or frequency is changed and only the beam position moves laterally. We demonstrated that in this method no bandwidth is required, so it is possible to reduce the background radiation noise by narrowband filtering of the carrier. The fidelity of the analog voice communication system which is made upon the IPM is satisfactory and we are able to transmit the audio signals up to 1Km.

High-volume optical vortex multiplexing and de-multiplexing for free-space optical communication.

PubMed

Wang, Zhongxi; Zhang, N; Yuan, X-C

2011-01-17

We report an approach to the increase of signal channels in free-space optical communication based on composed optical vortices (OVs). In the encoding process, conventional algorithm employed for the generation of collinearly superimposed OVs is combined with a genetic algorithm to achieve high-volume OV multiplexing. At the receiver end, a novel Dammann vortex grating is used to analyze the multihelix beams with a large number of OVs. We experimentally demonstrate a digitized system which is capable of transmitting and receiving 16 OV channels simultaneously. This system is expected to be compatible with a high-speed OV multiplexing technique, with potentials to extremely high-volume information density in OV communication.

Considerations for an Earth Relay Satellite with RF and Optical Trunklines

NASA Technical Reports Server (NTRS)

Israel, David J.

2016-01-01

Support for user platforms through the use of optical links to geosynchronous relay spacecraft are expected to be part of the future space communications architecture. The European Data Relay Satellite System (EDRS) has its first node, EDRS-A, in orbit. The EDRS architecture includes space-to-space optical links with a Ka-Band feeder link or trunkline. NASA's Laser Communications Relay Demonstration (LCRD) mission, originally baselined to support a space-to-space optical link relayed with an optical trunkline, has added an Radio Frequency (RF) trunkline. The use of an RF trunkline avoids the outages suffered by an optical trunkline due to clouds, but an RF trunkline will be bandwidth limited. A space relay architecture with both RF and optical trunklines could relay critical realtime data, while also providing a high data volume capacity. This paper considers the relay user scenarios that could be supported, and the implications to the space relay system and operations. System trades such as the amount of onboard processing and storage required, the use of link layer switching vs. network layer routing, and the use of Delay/Disruption Tolerant Networking (DTN) are discussed.

Networked Operations of Hybrid Radio Optical Communications Satellites

NASA Technical Reports Server (NTRS)

Hylton, Alan; Raible, Daniel

2014-01-01

In order to address the increasing communications needs of modern equipment in space, and to address the increasing number of objects in space, NASA is demonstrating the potential capability of optical communications for both deep space and near-Earth applications. The Integrated Radio Optical Communications (iROC) is a hybrid communications system that capitalizes on the best of both the optical and RF domains while using each technology to compensate for the other's shortcomings. Specifically, the data rates of the optical links can be higher than their RF counterparts, whereas the RF links have greater link availability. The focus of this paper is twofold: to consider the operations of one or more iROC nodes from a networking point of view, and to suggest specific areas of research to further the field. We consider the utility of Disruption Tolerant Networking (DTN) and the Virtual Mission Operation Center (VMOC) model.

Simulating Autonomous Telecommunication Networks for Space Exploration

NASA Technical Reports Server (NTRS)

Segui, John S.; Jennings, Esther H.

2008-01-01

Currently, most interplanetary telecommunication systems require human intervention for command and control. However, considering the range from near Earth to deep space missions, combined with the increase in the number of nodes and advancements in processing capabilities, the benefits from communication autonomy will be immense. Likewise, greater mission science autonomy brings the need for unscheduled, unpredictable communication and network routing. While the terrestrial Internet protocols are highly developed their suitability for space exploration has been questioned. JPL has developed the Multi-mission Advanced Communications Hybrid Environment for Test and Evaluation (MACHETE) tool to help characterize network designs and protocols. The results will allow future mission planners to better understand the trade offs of communication protocols. This paper discusses various issues with interplanetary network and simulation results of interplanetary networking protocols.

Identical synchronization of chaotic secure communication systems with channel induced coherence resonance

NASA Astrophysics Data System (ADS)

Sepantaie, Marc M.; Namazi, Nader M.; Sepantaie, Amir M.

2016-05-01

This paper is devoted to addressing the synchronization, and detection of random binary data exposed to inherent channel variations existing in Free Space Optical (FSO) communication systems. This task is achieved by utilizing the identical synchronization methodology of Lorenz chaotic communication system, and its synergetic interaction in adversities imposed by the FSO channel. Moreover, the Lorenz system has been analyzed, and revealed to induce Stochastic Resonance (SR) once exposed to Additive White Gaussian Noise (AWGN). In particular, the resiliency of the Lorenz chaotic system, in light of channel adversities, has been attributed to the success of the proposed communication system. Furthermore, this paper advocates the use of Haar wavelet transform for enhanced detection capability of the proposed chaotic communication system, which utilizes Chaotic Parameter Modulation (CPM) technique for means of transmission.

Emerging Communication Technologies (ECT) Phase 3 Final Report

NASA Technical Reports Server (NTRS)

Bastin, Gary L.; Harris, William G.; Bates, Lakesha D.; Nelson, Richard A.

2004-01-01

The Emerging Communication Technology (ECT) project investigated three First Mile communication technologies in support of NASA s Second Generation Reusable Launch Vehicle (2nd Gen RLV), Orbital Space Plane, Advanced Range Technology Working Group (ARTWG) and the Advanced Spaceport Technology Working Group (ASTWG). These First Mile technologies have the purpose of interconnecting mobile users with existing Range Communication infrastructures. ECT was a continuation of the Range Information System Management (RISM) task started in 2002. RISM identified the three advance communication technologies investigated under ECT. These were Wireless Ethernet (Wi-Fi), Free Space Optics (FSO), and Ultra Wideband (UWB). Due to the report s size, it has been broken into three volumes: 1) Main Report 2) Appendices 3) UWB.

An ATP System for Deep-Space Optical Communication

NASA Technical Reports Server (NTRS)

Lee, Shinhak; Irtuzm Gerardi; Alexander, James

2008-01-01

An acquisition, tracking, and pointing (ATP) system is proposed for aiming an optical-communications downlink laser beam from deep space. In providing for a direction reference, the concept exploits the mature technology of star trackers to eliminate the need for a costly and potentially hazardous laser beacon. The system would include one optical and two inertial sensors, each contributing primarily to a different portion of the frequency spectrum of the pointing signal: a star tracker (<10 Hz), a gyroscope (<50 Hz), and a precise fluid-rotor inertial angular-displacement sensor (sometimes called, simply, "angle sensor") for the frequency range >50 Hz. The outputs of these sensors would be combined in an iterative averaging process to obtain high-bandwidth, high-accuracy pointing knowledge. The accuracy of pointing knowledge obtainable by use of the system was estimated on the basis of an 8-cm-diameter telescope and known parameters of commercially available star trackers and inertial sensors: The single-axis pointing-knowledge error was found to be characterized by a standard deviation of 150 nanoradians - below the maximum value (between 200 and 300 nanoradians) likely to be tolerable in deep-space optical communications.

Advanced Communication Architectures and Technologies for Missions to the Outer Planets

NASA Technical Reports Server (NTRS)

Bhasin, K.; Hayden, J. L.

2001-01-01

Missions to the outer planets would be considerably enhanced by the implementation of a future space communication infrastructure that utilizes relay stations placed at strategic locations in the solar system. These relay stations would operate autonomously and handle remote mission command and data traffic on a prioritized demand access basis. Such a system would enhance communications from that of the current direct communications between the planet and Earth. The system would also provide high rate data communications to outer planet missions, clear communications paths during times when the sun occults the mission spacecraft as viewed from Earth, and navigational "lighthouses" for missions utilizing onboard autonomous operations. Additional information is contained in the original extended abstract.

Acousto-optic pointing and tracking systems for free-space laser communications

NASA Astrophysics Data System (ADS)

Nikulin, V.; Khandekar, R.; Sofka, J.; Tartakovsky, G.

2005-08-01

Implementation of long-range laser communication systems holds great promise for high-bandwidth applications. They are viewed as a technology that in the nearest future will handle most of the "last mile" communication traffic for the individual subscribers, corporate offices, military, and possibly deep space probes. Indeed, lasers allow for concentration of energy within tightly focused beams and narrow spectral interval, thus offering high throughput, information security, weight and size of components and power requirements that could not be matched by RF systems. However, the advantages of optical communication systems come in the same package with several major challenges. In particular, high data rates should be complemented by high-precision wide-bandwidth position control of a laser beam. In many applications the ability to maintain a link is affected by the complex maneuvers performed by mobile communication platforms, resident vibrations, and atmospheric effects. The search for the most effective and reliable way to shape and steer the laser beam is an on-going effort. This paper is focused on the application of acousto-optic technology as an alternative to electro-mechanical devices. With realization that an acousto-optic Bragg cell is only a component of the entire communication system, which should perform complex tasks of acquisition, pointing, and tracking of the remote terminal, we present an attempt to consider this problem from the "systems" point of view.

The Role of X-Rays in Future Space Navigation and Communication

NASA Technical Reports Server (NTRS)

Winternitz, Luke M. B.; Gendreau, Keith C.; Hasouneh, Monther A.; Mitchell, Jason W.; Fong, Wai H.; Lee, Wing-Tsz; Gavriil, Fotis; Arzoumanian, Zaven

2013-01-01

In the near future, applications using X-rays will enable autonomous navigation and time distribution throughout the solar system, high capacity and low-power space data links, highly accurate attitude sensing, and extremely high-precision formation flying capabilities. Each of these applications alone has the potential to revolutionize mission capabilities, particularly beyond Earth orbit. This paper will outline the NASA Goddard Space Flight Center vision and efforts toward realizing the full potential of X-ray navigation and communications.

Full-Duplex Digital Communication on a Single Laser Beam

NASA Technical Reports Server (NTRS)

Hazzard, D. A.; MacCannell, J. A.; Lee, G.; Selves, E. R.; Moore, D.; Payne, J. A.; Garrett, C. D.; Dahlstrom, N.; Shay, T. M.

2006-01-01

A proposed free-space optical communication system would operate in a full-duplex mode, using a single constant-power laser beam for transmission and reception of binary signals at both ends of the free-space optical path. The system was conceived for two-way data communication between a ground station and a spacecraft in a low orbit around the Earth. It has been estimated that in this application, a data rate of 10 kb/s could be achieved at a ground-station-to-spacecraft distance of 320 km, using a laser power of only 100 mW. The basic system concept is also applicable to terrestrial free-space optical communications. The system (see figure) would include a diode laser at one end of the link (originally, the ground station) and a liquid-crystal- based retroreflecting modulator at the other end of the link (originally, the spacecraft). At the laser end, the beam to be transmitted would be made to pass through a quarter-wave plate, which would convert its linear polarization to right circular polarization. For transmission of data from the laser end to the retroreflector end, the laser beam would be modulated with subcarrier phase-shift keying (SC-PSK). The transmitted beam would then pass through an aperture- sharing element (ASE) - basically, a mirror with a hole in it, used to separate the paths of the transmitted and received light beams. The transmitted beam would continue outward through a telescope (which, in the original application, would be equipped with a spacecraft-tracking system) that would launch the transmitted beam along the free-space optical path to the retroreflector end.

20-Gbps optical LiFi transport system.

PubMed

Ying, Cheng-Ling; Lu, Hai-Han; Li, Chung-Yi; Cheng, Chun-Jen; Peng, Peng-Chun; Ho, Wen-Jeng

2015-07-15

A 20-Gbps optical light-based WiFi (LiFi) transport system employing vertical-cavity surface-emitting laser (VCSEL) and external light injection technique with 16-quadrature amplitude modulation (QAM)-orthogonal frequency-division multiplexing (OFDM) modulating signal is proposed. Good bit error rate (BER) performance and clear constellation map are achieved in our proposed optical LiFi transport systems. An optical LiFi transport system, delivering 16-QAM-OFDM signal over a 6-m free-space link, with a data rate of 20 Gbps, is successfully demonstrated. Such a 20-Gbps optical LiFi transport system provides the advantage of a free-space communication link for high data rates, which can accelerate the visible laser light communication (VLLC) deployment.

Space station needs, attributes, and architectural options study. Volume 1: Missions and requirements

NASA Technical Reports Server (NTRS)

1983-01-01

Science and applications, NOAA environmental observation, commercial resource observations, commercial space processing, commercial communications, national security, technology development, and GEO servicing are addressed. Approach to time phasing of mission requirements, system sizing summary, time-phased user mission payload support, space station facility requirements, and integrated time-phased system requirements are also addressed.

Global, real-time ionosphere specification for end-user communication and navigation products

NASA Astrophysics Data System (ADS)

Tobiska, W.; Carlson, H. C.; Schunk, R. W.; Thompson, D. C.; Sojka, J. J.; Scherliess, L.; Zhu, L.; Gardner, L. C.

2010-12-01

Space weather’s effects upon the near-Earth environment are due to dynamic changes in the energy transfer processes from the Sun’s photons, particles, and fields. Of the space environment domains that are affected by space weather, the ionosphere is the key region that affects communication and navigation systems. The Utah State University (USU) Space Weather Center (SWC) is a developer and producer of commercial space weather applications. A key system-level component for providing timely information about the effects of space weather is the Global Assimilation of Ionospheric Measurements (GAIM) system. GAIM, operated by SWC, improves real-time communication and navigation systems by continuously ingesting up to 10,000 slant TEC measurements every 15-minutes from approximately 500 stations. Using a Kalman filter, the background output from the physics-based Ionosphere Forecast Model (IFM) is adjusted to more accurately represent the actual ionosphere. An improved ionosphere leads to more useful derivative products. For example, SWC runs operational code, using GAIM, to calculate and report the global radio high frequency (HF) signal strengths for 24 world cities. This product is updated every 15 minutes at http://spaceweather.usu.edu and used by amateur radio operators. SWC also developed and provides through Apple iTunes the widely used real-time space weather iPhone app called SpaceWx for public space weather education. SpaceWx displays the real-time solar, heliosphere, magnetosphere, thermosphere, and ionosphere drivers to changes in the total electron content, for example. This smart phone app is tip of the “iceberg” of automated systems that provide space weather data; it permits instant understanding of the environment surrounding Earth as it dynamically changes. SpaceWx depends upon a distributed network that connects satellite and ground-based data streams with algorithms to quickly process the measurements into geophysical data, incorporate those data into operational space physics models, and finally generate visualization products such as the images, plots, and alerts that can be viewed on SpaceWx. In a real sense, the space weather community is now able to transition research models into operations through “proofing” products such as real-time disseminated of information through smart phones. We describe upcoming improvements for moving space weather information through automated systems into final derivative products.

Effect of space flight on cytokine production

NASA Astrophysics Data System (ADS)

Sonnenfeld, Gerald

Space flight has been shown to alter many immunological responses. Among those affected are the production of cytokines, Cytokines are the messengers of the immune system that facilitate communication among cells that allow the interaction among cells leading to the development of immune responses. Included among the cytokines are the interferons, interleukins, and colony stimulating factors. Cytokines also facilitate communication between the immune system and other body systems, such as the neuroendocrine and musculoskeletal systems. Some cytokines also have direct protective effects on the host, such as interferon, which can inhibit the replication of viruses. Studies in both humans and animals indicate that models of space flight as well as actual space flight alter the production and action of cytokines. Included among these changes are altered interferon production, altered responsiveness of bone marrow cells to granulocyte/monocyte-colony stimulating factor, but no alteration in the production of interleukin-3. This suggests that there are selective effects of space flight on immune responses, i.e. not all cytokines are affected in the same fashion by space flight. Tissue culture studies also suggest that there may be direct effects of space flight on the cells responsible for cytokine production and action. The results of the above study indicate that the effects of space flight on cytokines may be a fundamental mechanism by which space flight not only affects immune responses, but also other biological systems of the human.

TDRS-L Pre-Launch Press Conference

NASA Image and Video Library

2014-01-21

CAPE CANAVERAL, Fla. – During a news conference at NASA's Kennedy Space Center in Florida, agency and contractor officials discussed preparations for the launch of NASA's Tracking and Data Relay Satellite, or TDRS-L, spacecraft. Participants included Clay Flinn, launch weather officer for the 45th Weather Squadron at Cape Canaveral Air Force Station, Fla. Seated behind Flinn is Andy Kopito, Civil Space Programs director for Boeing Space & Intelligence Systems in El Segundo, Calif. The TDRS-L spacecraft is the second of three new satellites designed to ensure vital operational continuity for NASA by expanding the lifespan of the Tracking and Data Relay Satellite System TDRSS fleet, which consists of eight satellites in geosynchronous orbit. The spacecraft provide tracking, telemetry, command and high bandwidth data return services for numerous science and human exploration missions orbiting Earth. These include NASA's Hubble Space Telescope and the International Space Station. TDRS-L has a high-performance solar panel designed for more spacecraft power to meet the growing S-band communications requirements. TDRSS is one of NASA Space Communication and Navigation’s SCaN three networks providing space communications to NASA’s missions. For more information more about TDRS-L, visit: http://www.nasa.gov/tdrs To learn more about SCaN, visit: www.nasa.gov/scan Photo credit: NASA/Frankie Martin

Orbital ATK CRS-7 What's on Board Science Briefing

NASA Image and Video Library

2017-04-17

NASA Television held two “What’s on Board” science mission briefings from Kennedy Space Center's Press Site to discuss some of the science headed to the International Space Station on Orbital ATK’s seventh commercial resupply services mission, CRS-7. Orbital ATK’s Cygnus spacecraft will carry more than 7,600 pounds of science research, crew supplies, and hardware to the orbiting laboratory. CRS-7 will lift off atop a United Launch Alliance Atlas V rocket from Space Launch Complex 41 at Cape Canaveral Air Force Station in Florida. Part I Briefing participants were: -Cheryl Warner, NASA Communications -Tara Ruttley, Associate Program Scientist, JSC -Michael Roberts, Deputy Chief Scientist, CASIS -Bryan Onate, Project Manager, Advanced Plant Habitat, Kennedy Space Center -Howard Levine, Project Scientist, Advanced Plant Habitat, Kennedy Space Center -Sourav Sinha, Principle Investigator for ADCs in Microgravity, Oncolinx -Julian Rubinfien, Genes in Space II winner -Sebastian Kraves, Co-founder, Genes in Space -Henry Martin, External Payloads Coordinator, NanoRacks -Davide Massutti, QB50 CubeSats, Von Karman Institute Part II Briefing participants were: -Jason Townsend, NASA Communications -Joe Fust, Mission Integrator, United Launch Alliance -Paul Escalera, Orbital ATK Staff Systems Engineer Part II Briefing participants were: -Jason Townsend, NASA Communications -Joe Fust, Mission Integrator, United Launch Alliance -Paul Escalera, Orbital ATK Staff Systems Engineer

Utility of Space Transportation System to Space Communication Community

NASA Technical Reports Server (NTRS)

Bronstein, L. M.

1975-01-01

A potentially cost effective technique was investigated of launching operational satellites into synchronous orbit using the space transportation system (STS). This technique uses an unguided spinning solid rocket motor as the means for boosting a satellite from a low altitude shuttle parking orbit into a synchronous transfer orbit. The spacecraft is then injected into a geosynchronous orbit by an apogee kick motor fired at transfer orbit apogee. The approach is essentially that used on all Delta and Atlas-Centaur launches of synchronous satellites with the shuttle orbiter performing the function of the first two stages of the Delta three stage launch vehicle and the perigee kick motor performing the function of the Delta third state. It is concluded that the STS can be useful to the space communication community as well as to other geostationary satellite system users if the recommended actions are implemented.

Population Analysis: Communicating About Anthropometry in Context

NASA Technical Reports Server (NTRS)

Thaxton, Sherry; Rajulu, Sudhakar

2009-01-01

This slide presentation reviews the importance of communications about anthropometry and population analysis in particular for the design of aerospace systems. The difficulty of providing anthropometric accomodation an entire range of the population is reviewed, and the importance of communication of the issues with human system integration is emphasized, and the analysis of population as it applies to existing human factors methodologies is a novel way to assist with the communication. The issues of space suit design and anthropometry is reviewed as an example.

A new generation of IC based beam steering devices for free-space optical communication

NASA Astrophysics Data System (ADS)

Bedi, Vijit

Free Space Optical (FSO) communication has tremendously advanced within the last decade to meet the ever increasing demand for higher communication bandwidth. Advancement in laser technology since its invention in the 1960's [1] attracted them to be the dominant source in FSO communication modules. The future of FSO systems lay in implementing semiconductor lasers due to their small size, power efficiency and mass fabrication abilities. In the near future, these systems are very likely to be used in space and ground based applications and revolutionary beam steering technologies will be required for distant communications in free-space. The highly directional characteristic inherent to a laser beam challenges and calls for new beam pointing and steering technologies for such type of communication. In this dissertation, research is done on a novel FSO communication device based on semiconductor lasers for high bandwidth communication. The "Fly eye transceiver" is an extremely wide steering bandwidth, completely non-mechanical FSO laser communication device primarily designed to replace traditional mechanical beam steering optical systems. This non-mechanical FSO device possesses a full spherical steering range and a very high tracking bandwidth. Inspired by the evolutionary model of a fly's eye, the full spherical steering range is assured by electronically controlled switching of its sub-eyes. Non mechanical technologies used in the past for beam steering such as acousto-optic Bragg cells, liquid crystal arrays or piezoelectric elements offer the wide steering bandwidth and fast response time, but are limited in their angular steering range. Mechanical gimbals offer a much greater steering range but face a much slower response time or steering bandwidth problem and often require intelligent adaptive controls with bulky driver amplifiers to feed their actuators. As a solution to feed both the fast and full spherical steering, the Fly-eye transceiver is studied as part of my PhD work. The design tool created for the research of the fly eye is then used to study different applications that may be implemented with the concept. Research is done on the mathematical feasibility, modeling, design, application of the technology, and its characterization in a simulation environment. In addition, effects of atmospheric turbulence on beam propagation in free space, and applying data security using optical encryption are also researched.

A study of a space communication system for the control and monitoring of the electric distribution system. Volume 2: Supporting data and analyses

NASA Technical Reports Server (NTRS)

Vaisnys, A.

1980-01-01

It is technically feasible to design a satellite communication system to serve the United States electric utility industry's needs relative to load management, real-time operations management, remote meter reading and to determine the costs of various elements of the system. The functions associated with distribution automation and control and communication system requirements are defined. Factors related to formulating viable communication concepts, the relationship of various design factors to utility operating practices, and the results of the cost analysis are discussed The system concept and several ways in which the concept could be integrated into the utility industry are described.

77 FR 53159 - Passenger Use of Portable Electronic Devices on Board Aircraft

Federal Register 2010, 2011, 2012, 2013, 2014

2012-08-31

... to navigation systems such as very high frequency (VHF) Omni Range (VOR) navigation systems. \\1\\ 14... navigation, communication, and surveillance radio receivers that may be susceptible at certain frequencies to... space by electromagnetic waves on specific radio frequencies that are used to communicate information...

Active Cooperation Between Primary Users and Cognitive Radio Users in Heterogeneous Ad-Hoc Networks

DTIC Science & Technology

2012-04-01

processing to wireless communications and networking, including space-time coding and modulation for MIMO wireless communications, MIMO - OFDM systems, and...multiinput-multioutput ( MIMO ) system that can significantly increase the link capacity and realize a new form of spatial diversity which has been termed

A Simulation Based Investigation of High Latency Space Systems Operations

NASA Technical Reports Server (NTRS)

Li, Zu Qun; Moore, Michael; Bielski, Paul; Crues, Edwin Z.

2017-01-01

This study was the first in a series of planned tests to use physics-based subsystem simulations to investigate the interactions between a spacecraft's crew and a ground-based mission control center for vehicle subsystem operations across long communication delays. The simulation models the life support system of a deep space habitat. It contains models of an environmental control and life support system, an electrical power system, an active thermal control systems, and crew metabolic functions. The simulation has three interfaces: 1) a real-time crew interface that can be use to monitor and control the subsystems; 2) a mission control center interface with data transport delays up to 15 minute each way; and 3) a real-time simulation test conductor interface used to insert subsystem malfunctions and observe the interactions between the crew, ground, and simulated vehicle. The study was conducted at the 21st NASA Extreme Environment Mission Operations (NEEMO) mission. The NEEMO crew and ground support team performed a number of relevant deep space mission scenarios that included both nominal activities and activities with system malfunctions. While this initial test sequence was focused on test infrastructure and procedures development, the data collected in the study already indicate that long communication delays have notable impacts on the operation of deep space systems. For future human missions beyond cis-lunar, NASA will need to design systems and support tools to meet these challenges. These will be used to train the crew to handle critical malfunctions on their own, to predict malfunctions and assist with vehicle operations. Subsequent more detailed and involved studies will be conducted to continue advancing NASA's understanding of space systems operations across long communications delays.

A Simulation Based Investigation of High Latency Space Systems Operations

NASA Technical Reports Server (NTRS)

Li, Zu Qun; Crues, Edwin Z.; Bielski, Paul; Moore, Michael

2017-01-01

This study was the first in a series of planned tests to use physics-based subsystem simulations to investigate the interactions between a spacecraft's crew and a ground-based mission control center for vehicle subsystem operations across long communication delays. The simulation models the life support system of a deep space habitat. It contains models of an environmental control and life support system, an electrical power system, an active thermal control system, and crew metabolic functions. The simulation has three interfaces: 1) a real-time crew interface that can be use to monitor and control the subsystems; 2) a mission control center interface with data transport delays up to 15 minute each way; and 3) a real-time simulation test conductor interface used to insert subsystem malfunctions and observe the interactions between the crew, ground, and simulated vehicle. The study was conducted at the 21st NASA Extreme Environment Mission Operations (NEEMO) mission. The NEEMO crew and ground support team performed a number of relevant deep space mission scenarios that included both nominal activities and activities with system malfunctions. While this initial test sequence was focused on test infrastructure and procedures development, the data collected in the study already indicate that long communication delays have notable impacts on the operation of deep space systems. For future human missions beyond cis-lunar, NASA will need to design systems and support tools to meet these challenges. These will be used to train the crew to handle critical malfunctions on their own, to predict malfunctions, and to assist with vehicle operations. Subsequent more detailed and involved studies will be conducted to continue advancing NASA's understanding of space systems operations across long communications delays.

TDRS-L Pre-Launch Press Conference

NASA Image and Video Library

2014-01-21

CAPE CANAVERAL, Fla. –During a news conference at NASA's Kennedy Space Center in Florida, agency and contractor officials discussed preparations for the launch of NASA's Tracking and Data Relay Satellite, or TDRS-L, spacecraft. Participating in the briefing, from the left, are Badri Younes, deputy associate administrator, Space Communications and Navigation SCaN NASA Human Exploration and Operations Mission Directorate at NASA Headquarters in Washington D.C., Tim Dunn, NASA launch director at Kennedy, Vernon Thorp, program manager for NASA Missions with United Launch Alliance in Denver, Colo., Jeffrey Gramling, NASA's TDRS-L project manager at the Goddard Space Flight Center in Greenbelt, Md., Andy Kopito, Civil Space Programs director for Boeing Space & Intelligence Systems in El Segundo, Calif., and Clay Flinn, launch weather officer for the 45th Weather Squadron at Cape Canaveral Air Force Station, Fla. The TDRS-L spacecraft is the second of three new satellites designed to ensure vital operational continuity for NASA by expanding the lifespan of the Tracking and Data Relay Satellite System TDRSS fleet, which consists of eight satellites in geosynchronous orbit. The spacecraft provide tracking, telemetry, command and high bandwidth data return services for numerous science and human exploration missions orbiting Earth. These include NASA's Hubble Space Telescope and the International Space Station. TDRS-L has a high-performance solar panel designed for more spacecraft power to meet the growing S-band communications requirements. TDRSS is one of NASA Space Communication and Navigation’s SCaN three networks providing space communications to NASA’s missions. For more information more about TDRS-L, visit: http://www.nasa.gov/tdrs To learn more about SCaN, visit: www.nasa.gov/scan Photo credit: NASA/Frankie Martin

TDRS-L Pre-Launch Press Conference

NASA Image and Video Library

2014-01-21

CAPE CANAVERAL, Fla. –During a news conference at NASA's Kennedy Space Center in Florida, agency and contractor officials discussed preparations for the launch of NASA's Tracking and Data Relay Satellite, or TDRS-L, spacecraft. Participating in the briefing, from the left, are George Diller of NASA Public Affairs, Badri Younes, deputy associate administrator, Space Communications and Navigation SCaN NASA Human Exploration and Operations Mission Directorate at NASA Headquarters in Washington D.C., Tim Dunn, NASA launch director at Kennedy, Vernon Thorp, program manager for NASA Missions with United Launch Alliance in Denver, Colo., Jeffrey Gramling, NASA's TDRS-L project manager at the Goddard Space Flight Center in Greenbelt, Md., Andy Kopito, Civil Space Programs director for Boeing Space & Intelligence Systems in El Segundo, Calif., and Clay Flinn, launch weather officer for the 45th Weather Squadron at Cape Canaveral Air Force Station, Fla. The TDRS-L spacecraft is the second of three new satellites designed to ensure vital operational continuity for NASA by expanding the lifespan of the Tracking and Data Relay Satellite System TDRSS fleet, which consists of eight satellites in geosynchronous orbit. The spacecraft provide tracking, telemetry, command and high bandwidth data return services for numerous science and human exploration missions orbiting Earth. These include NASA's Hubble Space Telescope and the International Space Station. TDRS-L has a high-performance solar panel designed for more spacecraft power to meet the growing S-band communications requirements. TDRSS is one of NASA Space Communication and Navigation’s SCaN three networks providing space communications to NASA’s missions. For more information more about TDRS-L, visit: http://www.nasa.gov/tdrs To learn more about SCaN, visit: www.nasa.gov/scan Photo credit: NASA/Frankie Martin

Overview of Intelligent Power Controller Development for the Deep Space Gateway

NASA Technical Reports Server (NTRS)

Csank, Jeffrey

2017-01-01

Intelligent, or autonomous, control of a spacecraft is an enabling technology that must be developed for deep space human exploration. NASAs current long term human space platform, the International Space Station, which is in Low Earth Orbit, is in almost continuous communication with ground based mission control. This allows near real-time control of all the vehicle core systems, including power, to be controlled by the ground. As focus shifts from Low Earth Orbit, communication time-lag and communication bandwidth limitations beyond geosynchronous orbit does not permit this type of operation. This presentation contains ongoing work at NASA to develop an architecture for autonomous power control and the vehicle manager which monitors, coordinates, and delegates to all the on-board subsystems to enable autonomous control of the complete spacecraft.

Dual-Use Space Technology Transfer Conference and Exhibition. Volume 1

NASA Technical Reports Server (NTRS)

Krishen, Kumar (Compiler)

1994-01-01

This document contains papers presented at the Dual-Use Space Technology Transfer Conference and Exhibition held at the Johnson Space Center February 1-3, 1994. Possible technology transfers covered during the conference were in the areas of information access; innovative microwave and optical applications; materials and structures; marketing and barriers; intelligent systems; human factors and habitation; communications and data systems; business process and technology transfer; software engineering; biotechnology and advanced bioinstrumentation; communications signal processing and analysis; new ways of doing business; medical care; applications derived from control center data systems; human performance evaluation; technology transfer methods; mathematics, modeling, and simulation; propulsion; software analysis and decision tools systems/processes in human support technology; networks, control centers, and distributed systems; power; rapid development perception and vision technologies; integrated vehicle health management; automation technologies; advanced avionics; ans robotics technologies. More than 77 papers, 20 presentations, and 20 exhibits covering various disciplines were presented b experts from NASA, universities, and industry.

Deep-space and near-Earth optical communications by coded orbital angular momentum (OAM) modulation.

PubMed

Djordjevic, Ivan B

2011-07-18

In order to achieve multi-gigabit transmission (projected for 2020) for the use in interplanetary communications, the usage of large number of time slots in pulse-position modulation (PPM), typically used in deep-space applications, is needed, which imposes stringent requirements on system design and implementation. As an alternative satisfying high-bandwidth demands of future interplanetary communications, while keeping the system cost and power consumption reasonably low, in this paper, we describe the use of orbital angular momentum (OAM) as an additional degree of freedom. The OAM is associated with azimuthal phase of the complex electric field. Because OAM eigenstates are orthogonal the can be used as basis functions for N-dimensional signaling. The OAM modulation and multiplexing can, therefore, be used, in combination with other degrees of freedom, to solve the high-bandwidth requirements of future deep-space and near-Earth optical communications. The main challenge for OAM deep-space communication represents the link between a spacecraft probe and the Earth station because in the presence of atmospheric turbulence the orthogonality between OAM states is no longer preserved. We will show that in combination with LDPC codes, the OAM-based modulation schemes can operate even under strong atmospheric turbulence regime. In addition, the spectral efficiency of proposed scheme is N2/log₂N times better than that of PPM.

Modified artificial fish school algorithm for free space optical communication with sensor-less adaptive optics system

NASA Astrophysics Data System (ADS)

Cao, Jingtai; Zhao, Xiaohui; Li, Zhaokun; Liu, Wei; Gu, Haijun

2017-11-01

The performance of free space optical (FSO) communication system is limited by atmospheric turbulent extremely. Adaptive optics (AO) is the significant method to overcome the atmosphere disturbance. Especially, for the strong scintillation effect, the sensor-less AO system plays a major role for compensation. In this paper, a modified artificial fish school (MAFS) algorithm is proposed to compensate the aberrations in the sensor-less AO system. Both the static and dynamic aberrations compensations are analyzed and the performance of FSO communication before and after aberrations compensations is compared. In addition, MAFS algorithm is compared with artificial fish school (AFS) algorithm, stochastic parallel gradient descent (SPGD) algorithm and simulated annealing (SA) algorithm. It is shown that the MAFS algorithm has a higher convergence speed than SPGD algorithm and SA algorithm, and reaches the better convergence value than AFS algorithm, SPGD algorithm and SA algorithm. The sensor-less AO system with MAFS algorithm effectively increases the coupling efficiency at the receiving terminal with fewer numbers of iterations. In conclusion, the MAFS algorithm has great significance for sensor-less AO system to compensate atmospheric turbulence in FSO communication system.

Recent advances in high-capacity free-space optical and radio-frequency communications using orbital angular momentum multiplexing.

PubMed

Willner, Alan E; Ren, Yongxiong; Xie, Guodong; Yan, Yan; Li, Long; Zhao, Zhe; Wang, Jian; Tur, Moshe; Molisch, Andreas F; Ashrafi, Solyman

2017-02-28

There is a continuing growth in the demand for data bandwidth, and the multiplexing of multiple independent data streams has the potential to provide the needed data capacity. One technique uses the spatial domain of an electromagnetic (EM) wave, and space division multiplexing (SDM) has become increasingly important for increased transmission capacity and spectral efficiency of a communication system. A subset of SDM is mode division multiplexing (MDM), in which multiple orthogonal beams each on a different mode can be multiplexed. A potential modal basis set to achieve MDM is to use orbital angular momentum (OAM) of EM waves. In such a system, multiple OAM beams each carrying an independent data stream are multiplexed at the transmitter, propagate through a common medium and are demultiplexed at the receiver. As a result, the total capacity and spectral efficiency of the communication system can be multiplied by a factor equal to the number of transmitted OAM modes. Over the past few years, progress has been made in understanding the advantages and limitations of using multiplexed OAM beams for communication systems. In this review paper, we highlight recent advances in the use of OAM multiplexing for high-capacity free-space optical and millimetre-wave communications. We discuss different technical challenges (e.g. atmospheric turbulence and crosstalk) as well as potential techniques to mitigate such degrading effects.This article is part of the themed issue 'Optical orbital angular momentum'. © 2017 The Author(s).

Recent advances in high-capacity free-space optical and radio-frequency communications using orbital angular momentum multiplexing

PubMed Central

Ren, Yongxiong; Xie, Guodong; Yan, Yan; Li, Long; Zhao, Zhe; Wang, Jian; Tur, Moshe; Molisch, Andreas F.; Ashrafi, Solyman

2017-01-01

There is a continuing growth in the demand for data bandwidth, and the multiplexing of multiple independent data streams has the potential to provide the needed data capacity. One technique uses the spatial domain of an electromagnetic (EM) wave, and space division multiplexing (SDM) has become increasingly important for increased transmission capacity and spectral efficiency of a communication system. A subset of SDM is mode division multiplexing (MDM), in which multiple orthogonal beams each on a different mode can be multiplexed. A potential modal basis set to achieve MDM is to use orbital angular momentum (OAM) of EM waves. In such a system, multiple OAM beams each carrying an independent data stream are multiplexed at the transmitter, propagate through a common medium and are demultiplexed at the receiver. As a result, the total capacity and spectral efficiency of the communication system can be multiplied by a factor equal to the number of transmitted OAM modes. Over the past few years, progress has been made in understanding the advantages and limitations of using multiplexed OAM beams for communication systems. In this review paper, we highlight recent advances in the use of OAM multiplexing for high-capacity free-space optical and millimetre-wave communications. We discuss different technical challenges (e.g. atmospheric turbulence and crosstalk) as well as potential techniques to mitigate such degrading effects. This article is part of the themed issue ‘Optical orbital angular momentum’. PMID:28069770

Installing the new PCE (Proximity Communications Equipment) hardware

NASA Image and Video Library

2005-06-29

ISS011-E-09799 (27 June 2005) --- Cosmonaut Sergei K. Krikalev, Expedition 11 commander representing Russia's Federal Space Agency, works with the new Proximity Communications Equipment (PCE) hardware of the ASN-M satellite navigation system for the European Automated Transfer Vehicle (ATV) “Jules Verne” in the Zvezda Service Module of the International Space Station. The ATV is scheduled to arrive at the Station next year.

Free Space Optical Communication in the Military Environment

DTIC Science & Technology

2014-09-01

Communications Commission FDA Food and Drug Administration FMV Full Motion Video FOB Forward Operating Base FOENEX Free-Space Optical Experimental Network...from radio and voice to chat message and email. Data-rich multimedia content, such as high-definition pictures, video chat, video files, and...introduction of full-motion video (FMV) via numerous different Intelligence Surveillance and Reconnaissance (ISR) systems, such as targeting pods on

Automation in the Space Station module power management and distribution Breadboard

NASA Technical Reports Server (NTRS)

Walls, Bryan; Lollar, Louis F.

1990-01-01

The Space Station Module Power Management and Distribution (SSM/PMAD) Breadboard, located at NASA's Marshall Space Flight Center (MSFC) in Huntsville, Alabama, models the power distribution within a Space Station Freedom Habitation or Laboratory module. Originally designed for 20 kHz ac power, the system is now being converted to high voltage dc power with power levels on a par with those expected for a space station module. In addition to the power distribution hardware, the system includes computer control through a hierarchy of processes. The lowest level process consists of fast, simple (from a computing standpoint) switchgear, capable of quickly safing the system. The next level consists of local load center processors called Lowest Level Processors (LLP's). These LLP's execute load scheduling, perform redundant switching, and shed loads which use more than scheduled power. The level above the LLP's contains a Communication and Algorithmic Controller (CAC) which coordinates communications with the highest level. Finally, at this highest level, three cooperating Artificial Intelligence (AI) systems manage load prioritization, load scheduling, load shedding, and fault recovery and management. The system provides an excellent venue for developing and examining advanced automation techniques. The current system and the plans for its future are examined.

KSC-08pd2979

NASA Image and Video Library

2008-09-30

CAPE CANAVERAL, Fla. - In the Space Station Processing Facility at NASA's Kennedy Space Center in Florida, Japanese Aerospace Exploration Agency, or JAXA, technicians begin to deploy an antenna from the Inter Orbit Communication System Extended Facility, or ICS-EF. The antenna and a pointing mechanism will be used to communicate with JAXA’s Data Relay Test Satellite, or DRTS. The ICS-EF will be launched, along with the Extended Facility and Experiment Logistics Module-Exposed Section, to the International Space Station aboard the space shuttle Endeavour on the STS-127mission targeted for launch on May 15, 2009. Photo credit: NASA/Kim Shiflett

KSC-08pd2981

NASA Image and Video Library

2008-09-30

CAPE CANAVERAL, Fla. - In the Space Station Processing Facility at NASA's Kennedy Space Center in Florida, Japanese Aerospace Exploration Agency, or JAXA, technicians test the deployment of an antenna from the Inter Orbit Communication System Extended Facility, or ICS-EF. The antenna and a pointing mechanism will be used to communicate with JAXA’s Data Relay Test Satellite, or DRTS. The ICS-EF will be launched, along with the Extended Facility and Experiment Logistics Module-Exposed Section, to the International Space Station aboard the space shuttle Endeavour on the STS-127mission targeted for launch on May 15, 2009. Photo credit: NASA/Kim Shiflett

KSC-08pd2986

NASA Image and Video Library

2008-09-30

CAPE CANAVERAL, Fla. - In the Space Station Processing Facility at NASA's Kennedy Space Center in Florida, Japanese Aerospace Exploration Agency, or JAXA, technicians test the deployment of an antenna and boom from the Inter Orbit Communication System Extended Facility, or ICS-EF. The antenna and a pointing mechanism will be used to communicate with JAXA’s Data Relay Test Satellite, or DRTS. The ICS-EF will be launched, along with the Extended Facility and Experiment Logistics Module-Exposed Section, to the International Space Station aboard the space shuttle Endeavour on the STS-127mission targeted for launch on May 15, 2009. Photo credit: NASA/Kim Shiflett

KSC-08pd2983

NASA Image and Video Library

2008-09-30

CAPE CANAVERAL, Fla. - In the Space Station Processing Facility at NASA's Kennedy Space Center in Florida, Japanese Aerospace Exploration Agency, or JAXA, technicians test the deployment of an antenna from the Inter Orbit Communication System Extended Facility, or ICS-EF. The antenna and a pointing mechanism will be used to communicate with JAXA’s Data Relay Test Satellite, or DRTS. The ICS-EF will be launched, along with the Extended Facility and Experiment Logistics Module-Exposed Section, to the International Space Station aboard the space shuttle Endeavour on the STS-127mission targeted for launch on May 15, 2009. Photo credit: NASA/Kim Shiflett

KSC-08pd2978

NASA Image and Video Library

2008-09-30

CAPE CANAVERAL, Fla. - In the Space Station Processing Facility at NASA's Kennedy Space Center in Florida, Japanese Aerospace Exploration Agency, or JAXA, technicians begin to deploy an antenna from the Inter Orbit Communication System Extended Facility, or ICS-EF. The antenna and a pointing mechanism will be used to communicate with JAXA’s Data Relay Test Satellite, or DRTS. The ICS-EF will be launched, along with the Extended Facility and Experiment Logistics Module-Exposed Section, to the International Space Station aboard the space shuttle Endeavour on the STS-127mission targeted for launch on May 15, 2009. Photo credit: NASA/Kim Shiflett

KSC-08pd2980

NASA Image and Video Library

2008-09-30

CAPE CANAVERAL, Fla. - In the Space Station Processing Facility at NASA's Kennedy Space Center in Florida, Japanese Aerospace Exploration Agency, or JAXA, technicians deploy an antenna from the Inter Orbit Communication System Extended Facility, or ICS-EF. The antenna and a pointing mechanism will be used to communicate with JAXA’s Data Relay Test Satellite, or DRTS. The ICS-EF will be launched, along with the Extended Facility and Experiment Logistics Module-Exposed Section, to the International Space Station aboard the space shuttle Endeavour on the STS-127mission targeted for launch on May 15, 2009. Photo credit: NASA/Kim Shiflett

KSC-08pd2984

NASA Image and Video Library

2008-09-30

CAPE CANAVERAL, Fla. - In the Space Station Processing Facility at NASA's Kennedy Space Center in Florida, Japanese Aerospace Exploration Agency, or JAXA, technicians test the deployment of an antenna and boom from the Inter Orbit Communication System Extended Facility, or ICS-EF. The antenna and a pointing mechanism will be used to communicate with JAXA’s Data Relay Test Satellite, or DRTS. The ICS-EF will be launched, along with the Extended Facility and Experiment Logistics Module-Exposed Section, to the International Space Station aboard the space shuttle Endeavour on the STS-127mission targeted for launch on May 15, 2009. Photo credit: NASA/Kim Shiflett

KSC-08pd2985

NASA Image and Video Library

2008-09-30

CAPE CANAVERAL, Fla. - In the Space Station Processing Facility at NASA's Kennedy Space Center in Florida, Japanese Aerospace Exploration Agency, or JAXA, technicians test the deployment of an antenna and boom from the Inter Orbit Communication System Extended Facility, or ICS-EF. The antenna and a pointing mechanism will be used to communicate with JAXA’s Data Relay Test Satellite, or DRTS. The ICS-EF will be launched, along with the Extended Facility and Experiment Logistics Module-Exposed Section, to the International Space Station aboard the space shuttle Endeavour on the STS-127mission targeted for launch on May 15, 2009. Photo credit: NASA/Kim Shiflett

Space construction engineering - A new career field

NASA Technical Reports Server (NTRS)

Hagler, T.

1979-01-01

Opportunities for engineers in the design and construction of future large space structures are outlined. Possible space structures for the 1980's include a large mirror to reflect sunlight to earth for night lighting, an antenna for a personal communications system, a deep space communications relay system and a large passive radiometer to measure soil moisture. Considerations in the design of such structures include the lack of gravity, allowing structures to be built with much less supporting weight, the cost of transportation to orbit, leading to the use of aluminum or composite materials stored on reels and attached to a beam builder, and the required surface accuracy in the presence of thermal stresses. Construction factors to consider include the use of astronauts and remote manipulators in assembly, both of which have been demonstrated to be feasible.

Development of Telecommunications of Prao ASC Lpi RAS

NASA Astrophysics Data System (ADS)

Isaev, E. A.; Dumskiy, D. V.; Likhachev, S. F.; Shatskaya, M. V.; Pugachev, V. D.; Samodurov, V. A.

The new modern and reliable data storage system was acquired in 2010 in order to develop internal telecommunication resources of the Observatory. The system is designed for store large amounts of observation data obtained from the three radio-astronomy complexes (PT-22, DKR-1000 and BSA). The digital switching system - "Elcom" is installed in the Pushchino Radio Astronomy Observatory to ensure the observatory by phone communications. The phone communication between buildings of the observatory carried out over fiber-optic data links by using the ip-telephony. The direct optical channel from tracking station RT-22 in Pushchino to Moscow processing center has been created and put into operation to transfer large amounts of data at the final stage of the establishment of ground infrastructure for the international space project "Radioastron". A separate backup system for processing and storing data is organized in Pushchino Radio Astronomy Observatory to eliminate data loss during communication sessions with the Space Telescope.

Radio frequency communication system utilizing radiating transmission lines

DOEpatents

Struven, Warren C.

1984-01-01

A radio communication system for use in tunnels, mines, buildings or other shielded locations in which a pair of radiating transmission lines (30), (31) extend through such location in spaced coextensive relation to each other. Each transmission line (30), (31) has at least one unidirectional amplifier (32), (33) interposed therein with the sense of the unidirectional amplifier (32) of one transmission line (30) being opposite to the sense of the unidirectional amplifier (33) of the other transmission line (31). Each of the amplifiers (32), (33) has a gain which is less than the coupling loss between the transmission lines (30), (31). Two or more mobile transceivers (35) in the location served by the system are coupled to the transmission lines (30), (31) by electromagnetic wave propagation in space in order to communicate directly with each other at a given radio frequency within the frequency range of the system.

NASA Communications Augmentation network

NASA Technical Reports Server (NTRS)

Omidyar, Guy C.; Butler, Thomas E.; Laios, Straton C.

1990-01-01

The NASA Communications (Nascom) Division of the Mission Operations and Data Systems Directorate (MO&DSD) is to undertake a major initiative to develop the Nascom Augmentation (NAUG) network to achieve its long-range service objectives for operational data transport to support the Space Station Freedom Program, the Earth Observing System (EOS), and other projects. The NAUG is the Nascom ground communications network being developed to accommodate the operational traffic of the mid-1990s and beyond. The NAUG network development will be based on the Open Systems Interconnection Reference Model (OSI-RM). This paper describes the NAUG network architecture, subsystems, topology, and services; addresses issues of internetworking the Nascom network with other elements of the Space Station Information System (SSIS); discusses the operations environment. This paper also notes the areas of related research and presents the current conception of how the network will provide broadband services in 1998.

Research on Formation of Microsatellite Communication with Genetic Algorithm

PubMed Central

Wu, Guoqiang; Bai, Yuguang; Sun, Zhaowei

2013-01-01

For the formation of three microsatellites which fly in the same orbit and perform three-dimensional solid mapping for terra, this paper proposes an optimizing design method of space circular formation order based on improved generic algorithm and provides an intersatellite direct spread spectrum communication system. The calculating equation of LEO formation flying satellite intersatellite links is guided by the special requirements of formation-flying microsatellite intersatellite links, and the transmitter power is also confirmed throughout the simulation. The method of space circular formation order optimizing design based on improved generic algorithm is given, and it can keep formation order steady for a long time under various absorb impetus. The intersatellite direct spread spectrum communication system is also provided. It can be found that, when the distance is 1 km and the data rate is 1 Mbps, the input wave matches preferably with the output wave. And LDPC code can improve the communication performance. The correct capability of (512, 256) LDPC code is better than (2, 1, 7) convolution code, distinctively. The design system can satisfy the communication requirements of microsatellites. So, the presented method provides a significant theory foundation for formation-flying and intersatellite communication. PMID:24078796

Research on formation of microsatellite communication with genetic algorithm.

PubMed

Wu, Guoqiang; Bai, Yuguang; Sun, Zhaowei

2013-01-01

For the formation of three microsatellites which fly in the same orbit and perform three-dimensional solid mapping for terra, this paper proposes an optimizing design method of space circular formation order based on improved generic algorithm and provides an intersatellite direct spread spectrum communication system. The calculating equation of LEO formation flying satellite intersatellite links is guided by the special requirements of formation-flying microsatellite intersatellite links, and the transmitter power is also confirmed throughout the simulation. The method of space circular formation order optimizing design based on improved generic algorithm is given, and it can keep formation order steady for a long time under various absorb impetus. The intersatellite direct spread spectrum communication system is also provided. It can be found that, when the distance is 1 km and the data rate is 1 Mbps, the input wave matches preferably with the output wave. And LDPC code can improve the communication performance. The correct capability of (512, 256) LDPC code is better than (2, 1, 7) convolution code, distinctively. The design system can satisfy the communication requirements of microsatellites. So, the presented method provides a significant theory foundation for formation-flying and intersatellite communication.

Video semaphore decoding for free-space optical communication

NASA Astrophysics Data System (ADS)

Last, Matthew; Fisher, Brian; Ezekwe, Chinwuba; Hubert, Sean M.; Patel, Sheetal; Hollar, Seth; Leibowitz, Brian S.; Pister, Kristofer S. J.

2001-04-01

Using teal-time image processing we have demonstrated a low bit-rate free-space optical communication system at a range of more than 20km with an average optical transmission power of less than 2mW. The transmitter is an autonomous one cubic inch microprocessor-controlled sensor node with a laser diode output. The receiver is a standard CCD camera with a 1-inch aperture lens, and both hardware and software implementations of the video semaphore decoding algorithm. With this system sensor data can be reliably transmitted 21 km form San Francisco to Berkeley.

Reports on work in support of NASA's tracking and communication division

NASA Technical Reports Server (NTRS)

Feagin, Terry; Lekkos, Anthony

1991-01-01

This is a report on the research conducted during the period October 1, 1991 through December 31, 1991. The research is divided into two primary areas: (1) generalization of the Fault Isolation using Bit Strings (FIBS) technique to permit fuzzy information to be used to isolate faults in the tracking and communications system of the Space Station; and (2) a study of the activity that should occur in the on board systems in order to attempt to recover from failures that are external to the Space Station.

Rethinking Communication in Innovation Processes: Creating Space for Change in Complex Systems

ERIC Educational Resources Information Center

Leeuwis, Cees; Aarts, Noelle

2011-01-01

This paper systematically rethinks the role of communication in innovation processes, starting from largely separate theoretical developments in communication science and innovation studies. Literature review forms the basis of the arguments presented. The paper concludes that innovation is a collective process that involves the contextual…

Development of a safe ground to space laser propagation system for the optical communications telescope laboratory

NASA Technical Reports Server (NTRS)

Wu, Janet P.

2003-01-01

Furthering pursuits in high bandwidth communications to future NASA deep space and neat-Earth probes, the Jet Propulsion Laboratory (JPL) is building the Optical communications Telescope Laboratory (OCTL) atop Table Mountain in Southern California. This R&D optical antenna will be used to develop optical communication strategies for future optical ground stations. Initial experiments to be conducted include propagating high-powered, Q-switched laser beams to retro-reflecting satellites. Yet laser beam propagation from the ground to space is under the cognizance of various government agencies, namely: the Occupational Safety and Health Administration (ISHA) that is responsible for protecting workforce personnel; the Federal Aviation Administration (FAA) responsible for protecting pilots and aircraft; and the Laser Clearinghouse of Space Command responsible for protecting space assets. To ensure that laser beam propagation from the OCTL and future autonomously operated ground stations comply with the guidelines of these organizations, JPL is developing a multi-tiered safety system that will meet the coordination, monitoring, and reporting functions required by the agencies. At Tier 0, laser operators will meet OSHA safety standards for protection and access to the high power lasers area will be restricted and interlocked. Tier 1, the area defined from the telescope dome out to a range of 3.4-km, will utilize long wave infrared camera sensors to alert operators of at risk aircraft in the FAA controlled airspace. Tier 2, defined to extend from 3.4-km out to the aircraft service ceiling in FAA airspace, will detect at risk aircraft by radar. Lastly, beam propagation into space, defined as Tier 3, will require coordination with the Laser Clearinghouse. A detailed description of the four tiers is presented along with the design of the integrated monitoring and beam transmission control system.

Technology for space station

NASA Astrophysics Data System (ADS)

Colladay, R. S.; Carlisle, R. F.

1984-10-01

Some of the most significant advances made in the space station discipline technology program are examined. Technological tasks and advances in the areas of systems/operations, environmental control and life support systems, data management, power, thermal considerations, attitude control and stabilization, auxiliary propulsion, human capabilities, communications, and structures, materials, and mechanisms are discussed. An overview of NASA technology planning to support the initial space station and the evolutionary growth of the space station is given.

KENNEDY SPACE CENTER, FLA. - At the Astrotech Space Operations processing facilities, NASA’s MESSENGER spacecraft is secure after transfer to the work stand. There employees of the Johns Hopkins University Applied Physics Laboratory, builders of the spacecraft, will perform an initial state-of-health check. Then processing for launch can begin, including checkout of the power systems, communications systems and control systems. The thermal blankets will also be attached for flight. MESSENGER - short for MErcury Surface, Space ENvironment, GEochemistry and Ranging - will be launched May 11 on a six-year mission aboard a Boeing Delta II rocket. Liftoff is targeted for 2:26 a.m. EDT on Tuesday, May 11.

NASA Image and Video Library

2004-03-10

KENNEDY SPACE CENTER, FLA. - At the Astrotech Space Operations processing facilities, NASA’s MESSENGER spacecraft is secure after transfer to the work stand. There employees of the Johns Hopkins University Applied Physics Laboratory, builders of the spacecraft, will perform an initial state-of-health check. Then processing for launch can begin, including checkout of the power systems, communications systems and control systems. The thermal blankets will also be attached for flight. MESSENGER - short for MErcury Surface, Space ENvironment, GEochemistry and Ranging - will be launched May 11 on a six-year mission aboard a Boeing Delta II rocket. Liftoff is targeted for 2:26 a.m. EDT on Tuesday, May 11.

KENNEDY SPACE CENTER, FLA. - At the Astrotech Space Operations processing facilities, NASA’s MESSENGER spacecraft is lifted off the pallet for transfer to a work stand. There employees of the Johns Hopkins University Applied Physics Laboratory, builders of the spacecraft, will perform an initial state-of-health check. Then processing for launch can begin, including checkout of the power systems, communications systems and control systems. The thermal blankets will also be attached for flight. MESSENGER - short for MErcury Surface, Space ENvironment, GEochemistry and Ranging - will be launched May 11 on a six-year mission aboard a Boeing Delta II rocket. Liftoff is targeted for 2:26 a.m. EDT on Tuesday, May 11.

NASA Image and Video Library

2004-03-10

KENNEDY SPACE CENTER, FLA. - At the Astrotech Space Operations processing facilities, NASA’s MESSENGER spacecraft is lifted off the pallet for transfer to a work stand. There employees of the Johns Hopkins University Applied Physics Laboratory, builders of the spacecraft, will perform an initial state-of-health check. Then processing for launch can begin, including checkout of the power systems, communications systems and control systems. The thermal blankets will also be attached for flight. MESSENGER - short for MErcury Surface, Space ENvironment, GEochemistry and Ranging - will be launched May 11 on a six-year mission aboard a Boeing Delta II rocket. Liftoff is targeted for 2:26 a.m. EDT on Tuesday, May 11.