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Sample records for communication systems design

  1. Expert system to design communications circuits

    SciTech Connect

    Tolendino, L.F.; Vahle, M.O.

    1986-07-01

    An expert system has been created to aid the design of fiber optic based communications circuits. The design system is based on an Apollo workstation, LISP and CPSL, an in-house developed expert system language. The optical circuit is taken from design specification through hardware selection and circuit routing to the production of detailed schematics and routing guides. A database containing the entire fiber optic trunk system is also maintained.

  2. System Design for Nano-Network Communications

    NASA Astrophysics Data System (ADS)

    ShahMohammadian, Hoda

    The potential applications of nanotechnology in a wide range of areas necessities nano-networking research. Nano-networking is a new type of networking which has emerged by applying nanotechnology to communication theory. Therefore, this dissertation presents a framework for physical layer communications in a nano-network and addresses some of the pressing unsolved challenges in designing a molecular communication system. The contribution of this dissertation is proposing well-justified models for signal propagation, noise sources, optimum receiver design and synchronization in molecular communication channels. The design of any communication system is primarily based on the signal propagation channel and noise models. Using the Brownian motion and advection molecular statistics, separate signal propagation and noise models are presented for diffusion-based and flow-based molecular communication channels. It is shown that the corrupting noise of molecular channels is uncorrelated and non-stationary with a signal dependent magnitude. The next key component of any communication system is the reception and detection process. This dissertation provides a detailed analysis of the effect of the ligand-receptor binding mechanism on the received signal, and develops the first optimal receiver design for molecular communications. The bit error rate performance of the proposed receiver is evaluated and the impact of medium motion on the receiver performance is investigated. Another important feature of any communication system is synchronization. In this dissertation, the first blind synchronization algorithm is presented for the molecular communication channels. The proposed algorithm uses a non-decision directed maximum likelihood criterion for estimating the channel delay. The Cramer-Rao lower bound is also derived and the performance of the proposed synchronization algorithm is evaluated by investigating its mean square error.

  3. Integrated source and channel encoded digital communication system design study

    NASA Technical Reports Server (NTRS)

    Huth, G. K.; Udalov, S.

    1974-01-01

    This study investigated the configuration and integration of a wideband communication system with a Ku-band rendezvous radar system. The goal of the study was to provide as much commonality between the two systems as possible. The antenna design was described with the only change being the requirement for dual polarization (linear for the radar system and circular for the communication system).

  4. a System Design and Analysis for Satellite Communication Link

    NASA Astrophysics Data System (ADS)

    Chung, Tae-Jin; Eun, Jong-Won

    2000-12-01

    A satellite RF communication link is analyzed based on a simple fundamental equations by systematic approach in this paper. The number of variables related to a design and analysis of satellite RF link is often a dozen or more, thus it is a tedious and time-consuming task. With the given input data, the important parameters are calculated step by step and three communication characteristics such as communication channel capacity, carrier-to-noise ratio (CNR) at the satellite and ground station are analyzed. It gives very useful information to the system engineers for designing and analyzing the overall satellite communication system in the conceptual design phase.

  5. Integrated source and channel encoded digital communication system design study

    NASA Technical Reports Server (NTRS)

    Alem, W. K.; Huth, G. K.; Simon, M. K.

    1978-01-01

    The particular Ku-band carrier, PN despreading, and symbol synchronization strategies, which were selected for implementation in the Ku-band transponder aboard the orbiter, were assessed and evaluated from a systems performance viewpoint, verifying that system specifications were met. A study was performed of the design and implementation of tracking techniques which are suitable for incorporation into the Orbiter Ku-band communication system. Emphasis was placed on maximizing tracking accuracy and communication system flexibility while minimizing cost, weight, and system complexity of Orbiter and ground systems hardware. The payload communication study assessed the design and performance of the forward link and return link bent-pipe relay modes for attached and detached payloads. As part of this study, a design for a forward link bent-pipe was proposed which employs a residual carrier but which is tracked by the existing Costas loop.

  6. Marco (Medical Record Communications) - System Concept, Design and Evaluation

    PubMed Central

    Moffatt, P. H.; Heisler, B. D.; Mela, W. D.; Alpert, J. J.; Goldstein, H.M.

    1978-01-01

    MARCO, an interfacility communication system, has been designed to promote safe relevant health care delivery to the inner city pediatric patient receiving care in a network consisting of Boston City Hospital and its affiliated Neighborhood Health Centers. This application of computer technology to communication of medical information compiled on an individual patient in multiple locations has implications for private group practice as well as other urban networks similar to our own. This paper provides the MARCO system concept, the system design and evaluation of its success after two years of operation.

  7. Simulation system architecture design for generic communications link

    NASA Technical Reports Server (NTRS)

    Tsang, Chit-Sang; Ratliff, Jim

    1986-01-01

    This paper addresses a computer simulation system architecture design for generic digital communications systems. It addresses the issues of an overall system architecture in order to achieve a user-friendly, efficient, and yet easily implementable simulation system. The system block diagram and its individual functional components are described in detail. Software implementation is discussed with the VAX/VMS operating system used as a target environment.

  8. 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.

  9. Integrated source and channel encoded digital communication system design study

    NASA Technical Reports Server (NTRS)

    Huth, G. K.; Trumpis, B. D.; Udalov, S.

    1975-01-01

    Various aspects of space shuttle communication systems were studied. The following major areas were investigated: burst error correction for shuttle command channels; performance optimization and design considerations for Costas receivers with and without bandpass limiting; experimental techniques for measuring low level spectral components of microwave signals; and potential modulation and coding techniques for the Ku-band return link. Results are presented.

  10. Energy-quality system design for in-body communication.

    PubMed

    Zhang, Yuwei; Li, Ye; Qiao, Dengyu; Zhang, Yuanting

    2009-01-01

    With the explosive development of wireless communication technology, more and more implanted medical devices appear in everyday life. Because of the limited energy resource in implanted devices, the energy-quality wireless system design is the biggest challenge. In this paper, we update our former system level energy model and make it suitable for implantable medical communication system. In the new model, the impacts of human body tissue on the signal transmission are considered. The wireless system energy consumption is minimized by adjusting the digital base-band and RF parameters such as signal bandwidth, peak-to-average ratio (PAR), modulation levels, data rates etc. In the communication quality evaluation, we consider the effects of 1/f noise and the third-order harmonic distortion in addition to normal channel noise. PMID:19963632

  11. Design and evaluation of control systems for large communications satellites

    NASA Technical Reports Server (NTRS)

    Steiber, M. E.

    1985-01-01

    Control techniques for future large flexible spacecraft are developed. Control design and analysis are supported by a comprehensive CAD system. The proposed operational mobile communications satellite (OMSAT) featuring a 44 m offset fed antenna is used as target application. Requirements for satellite attitude control and communications beam pointing are defined. The following control methods are applied to the system: standard linear optimal regulator (LOR) with Luenberger observer, LOR/observer with selective spill-over suppression, frequency shaped LOR, LOR with closed-loop order reduction by cost decoupling, and robust servomechanism.

  12. Orbital design strategy for domestic communication satellite systems.

    NASA Technical Reports Server (NTRS)

    Ramji, S.; Sawitz, P.

    1973-01-01

    Review of some of the considerations pertinent to efficient orbit utilization in the design of domestic communications satellite systems. A strategy is developed to efficiently locate a heterogeneous system of satellites within the available arc and provide room for future growth. A practical design is illustrated, using a computer simulation model, for the placement of 25 satellites within 73% of the available arc employing frequency and polarization coordination techniques. A number of widely variable factors that influence satellite spacing are examined. These factors include such critical system elements as telephony and television interference noise limits, frequency plan coordination, polarization plan coordination, ground antenna diameter, signal protection ratio, and satellite station keeping.

  13. Effect of attenuation models on communication system design

    NASA Technical Reports Server (NTRS)

    Shimabukuro, Fred I.

    1995-01-01

    The atmosphere has a significant impact on the design of a global communication system operating at 20 GHz. The system under consideration has a total atmospheric link attenuation budget that is less than 6 dB. For this relatively small link margin, rain, cloud, and molecular attenuation have to be taken into account. For an assessment of system performance on a global basis, attenuation models are utilized. There is concern whether current models can adequately describe the atmospheric effects such that a system planner can properly allocate his resources for superior overall system performance. The atmospheric attenuation as predicted by models will be examined.

  14. Study and design on USB wireless laser communication system

    NASA Astrophysics Data System (ADS)

    Wang, Aihua; Zheng, Jiansheng; Ai, Yong

    2004-04-01

    We give the definition of USB wireless laser communication system (WLCS) and the brief introduction to the protocol of USB, the standard of hardware is also given. The paper analyses the hardware and software of USB WLCS. Wireless laser communication part and USB interface circuit part are discussed in detail. We also give the periphery design of the chip AN2131Q, the control circuit to realize the transformation from parallel port to serial bus, and the circuit of laser sending and receiving of laser communication part, which are simply, cheap and workable. And then the four part of software are analyzed as followed. We have consummated the ISR in the firmware frame to develop the periphery device of USB. We have debugged and consummated the 'ezload,' and the GPD of the drivers. Windows application performs functions and schedules the corresponding API functions to let the interface practical and beautiful. The system can realize USB wireless laser communication between computers, which distance is farther than 50 meters, and top speed can be bigger than 8 Mbps. The system is of great practical sense to resolve the issues of high-speed communication among increasing districts without fiber trunk network.

  15. A process for free-space laser communications system design

    NASA Astrophysics Data System (ADS)

    Walther, Frederick G.; Moores, John D.; Murphy, Robert J.; Michael, Steven; Nowak, George A.

    2009-08-01

    We present a design methodology for free-space laser communications systems. The first phase includes a characterization through numerical simulations of the channel to evaluate the range of extinction and scintillation. The second phase is the selection of fade mitigation schemes, which would incorporate pointing, acquisition, tracking, and communication system parameters specifically tailored to the channel. Ideally, the process would include sufficient flexibility to adapt to a wide range of channel conditions. We provide an example of the successful application of this design approach to a recent set of field experiments. This work was sponsored by the Department of Defense, RRCO DDR&E, under Air Force Contract FA8721-05-C-0002. Opinions, interpretations, conclusions and recommendations are those of the authors and are not necessarily endorsed by the United States Government.

  16. Design of fiber-optic digital communication systems. Introductory course for students in communications engineering

    NASA Astrophysics Data System (ADS)

    Eftimov, T. A.

    1991-04-01

    The handbook intends to provide the basic concepts about the components necessary to design a fiber-optic link and the communication system itself. A student or a beginner in optical fiber communications is introduced to the basic concepts, characteristics, and parameters of the components from a practical point of view. Therefore, the text is heavily illustrated. The mathematics involved is reduced to the absolute minimum and all of the calculations can be performed with a simple pocket calculator. Unlike most university textbooks, the practical parameters of devices needed as ordering information are specially outlined. Special attention was paid to simplified design examples of the most typical up-to-date digital communication systems. These together with the problems should help the student acquire the minimum but solid knowledge in this so rapidly developing communications world.

  17. Communications systems design for testability: Grey-box testing

    NASA Astrophysics Data System (ADS)

    Probert, Robert L.; Geldrez, Cecilia

    Large systems such as telecommunications systems may involve several million lines of executable code and tend to evolve incrementally, thus rendering testing and maintainability a very complex task. For this reason, testing and verification requirements must be defined and incorporated into the development process early in the software development cycle. Thus, design becomes a key component of these systems. An approach to assist in enhancing the testability of software designs is proposed, termed grey-box testing. One particular grey-box testing paradigm named semantic instrumentation is illustrated. Designs are represented as design machines, an extension of finite-state machines. A design-level plan for verification/test is then derived to guarantee branch coverage of the design machine for both normal behaviors and for processing of exceptions. Finally, semantic probes are defined to provide a mapping from the design machine to implemented code. These probes are used to document design decisions, implementation decisions, and execution traces during code verification and test. The process of semantic instrumentation is illustrated on communications services, more precisely, on the service of the alternating bit protocol.

  18. On the design of chaos-based secure communication systems

    NASA Astrophysics Data System (ADS)

    Zaher, Ashraf A.; Abu-Rezq, Abdulnasser

    2011-09-01

    This paper discusses the topic of using chaotic models for constructing secure communication systems. It investigates three different case studies that use encryption/decryption functions with varying degrees of complexity and performance. The first case study explores synchronization of identical chaotic systems, which is considered the most crucial step when developing chaos-based secure communication systems. It proposes a fast mechanism for synchronizing the transmitter and the receiver that is based on the drive-response approach. The superiority and causality of this mechanism is demonstrated via contrasting its performance and practical implementation against that of the traditional method of Pecora and Carroll. The second case study explores the use of an improved cryptography method for improving the scrambling of the transmitted signals. The improvement is based on using both the transmitter states and parameters for performing the encryption. The security analysis of this method is analyzed, highlighting its advantages and limitation, via simulating intruder attacks to the communication channel. Finally, the third case study augments a parameter update law to the previous two designs such that the encryption method is more robust. It uses a decoupling technique for which the synchronization process is completely isolated from the parameter identification algorithm. The Lorenz system was used to exemplify all the suggested techniques, and the transmission of both analog and digital signals was explored, while investigating various techniques to optimize the performance of the proposed systems.

  19. Design study LANDSAT follow-on mission unique communications system

    NASA Technical Reports Server (NTRS)

    1976-01-01

    Spacecraft subsystem design, performance evaluation, and system tradeoffs are presented for the LANDSAT follow-on mission (LF/O) spacecraft to TDRSS link for the transmission of thematic mapper (TM) and multispectral scanner (MSS) data and for the LF/O spacecraft to STDN and other direct users link for the transmission of TM data. Included are requirements definition, link analysis, subsystem and hardware tradeoffs, conceptual selection, hardware definition, and identification of required new technology. Cost estimates of the recommended communication system including both recurring and non recurring costs are discussed.

  20. Organizational Culture and the Design of Computer-Mediated Communication Systems: Issues for Organizational Communication Research.

    ERIC Educational Resources Information Center

    Hacker, Kenneth L.; And Others

    The study of computer mediated communication (CMC) systems in organizations is necessary for a complete examination and explanation of organizational culture and communication. Research has shown that the effects of CMC systems have been both positive and negative. Positively, they have helped to augment oral communication. Negatively, they have…

  1. Integrated source and channel encoded digital communications system design study

    NASA Technical Reports Server (NTRS)

    Huth, G. K.

    1974-01-01

    Studies on the digital communication system for the direct communication links from ground to space shuttle and the links involving the Tracking and Data Relay Satellite (TDRS). Three main tasks were performed:(1) Channel encoding/decoding parameter optimization for forward and reverse TDRS links,(2)integration of command encoding/decoding and channel encoding/decoding; and (3) modulation coding interface study. The general communication environment is presented to provide the necessary background for the tasks and to provide an understanding of the implications of the results of the studies.

  2. Integrated communication and control systems. II - Design considerations

    NASA Technical Reports Server (NTRS)

    Ray, Asok; Halevi, Yoram

    1988-01-01

    The ICCS design issues for nonperiodic and stochastic delays are addressed and the framework for alternative design procedures is outlined. The impact of network-induced delays on system stability is investigated and their physical significance is demonstrated using a simulation. The negative effects of vacant sampling and message rejection at the controller are demonstrated.

  3. COPTRAN - A method of optimum communication systems design

    NASA Technical Reports Server (NTRS)

    Brinkman, K. L.; Pratt, W. K.; Stokes, L. S.; Weber, J. W.

    1970-01-01

    Single set of mathematical expressions describes system cost and probability of error of data transmission in terms of four basic parameters in the link equation. A Lagrange multiplier sets up equations whose solutions yield the optimum values for system design considerations and weight and cost values.

  4. Integrated source and channel encoded digital communication system design study

    NASA Technical Reports Server (NTRS)

    Udalov, S.; Huth, G. K.

    1977-01-01

    The analysis of the forward link signal structure for the shuttle orbiter Ku-band communication system was carried out, based on the assumptions of a 3.03 Mcps PN code. It is shown that acquisition requirements for the forward link can be met at the acquisition threshold C/N0 sub 0 value of about 60 dB-Hz, which corresponds to a bit error rate (BER) of about 0.001. It is also shown that the tracking threshold for the forward link is at about 57 dB-Hz. The analysis of the bent pipe concept for the orbiter was carried out, along with the comparative analysis of the empirical data. The complexity of the analytical approach warrants further investigation to reconcile the empirical and theoretical results. Techniques for incorporating a text and graphics capability into the forward link data stream are considered and a baseline configuration is described.

  5. Design of ground testing systems which are compatible with two kinds of communication terminals

    NASA Astrophysics Data System (ADS)

    Jia, Jian-jun; Yang, Ming-dong; Zhang, Liang; Wu, Jin-cai

    2013-08-01

    Space laser communication and space quantum communication are all space optical communication, they are similar in communication links, high accuracy tracking and pointing, ground testing etc. The characters of space optical communication determine the necessity of testing and verifying communication terminals, for example, the laser beam reach diffraction limit in space laser communication, weak light detection or single photon detection should be carried out in space quantum communication, communication terminals are relatively moving refer to the ground station, and the terminals should have high quality in tracking target and pointing laser beam, so good system should be used in testing and verifying communication terminals. In this paper we did research on ground testing and verifying systems, we developed optical paths and two ground testing and verifying systems which are compatible with space laser communication and space quantum communication, the two systems contain one laboratory used system and one portable outfield used system. The laboratory used system mainly contains optical communication terminal, two dimensional (2D) simulation turntable, collimator and rear optical path, it can simulate the moving environment, transmission channel and relative motion of the satellite to ground or inter-satellite optical communication, it can also fully test the condition and performance of the optical communication terminals. The portable outfield used system mainly contains opto-mechanical subsystem, 2D turntable, electronic cabinet. The opto-mechanical subsystem is installed on the 2D turntable, it contains front and rear optical path. Electronic cabinet contains industry computer, turntable controller, GPS radio and optical controller, it mainly executes data acquisition, receiving and transmitting command. The portable outfield used system can be used in outfield, to help testing and verifying space-borne equipment. The design breaks through several

  6. A low-power photovoltaic system with energy storage for radio communications: description and design methodology

    SciTech Connect

    Chapman, C.P.; Chapman, P.D.

    1982-01-01

    A low power photovoltaic system was constructed with approximately 500 amp hours of battery energy storage to provide power to an emergency amateur radio communications center. The system can power the communications center for about 72 hours of continuous nonsun operation. Complete construction details and a design methodology algorithm are given with abundant engineering data and adequate theory to allow similar systems to be constructed, scaled up or down, with minimum design effort.

  7. Low-power photovoltaic system with energy storage for radio communications. Description and design methodology

    SciTech Connect

    Chapman, C.P.; Chapman, P.D.; Lewison, A.H.

    1982-01-15

    A low-power photovoltaic system was constructed with approximately 500 amp-hours of battery energy storage to provide power to an emergency amateur radio communications center. The system can power the communications center for about 72 hours of continuous no-sun operation. Complete construction details and a design methodology algorithm are given with abundant engineering data and adequate theory to allow similar systems to be constructed, scaled up or down, with minimum design effort.

  8. A low-power photovoltaic system with energy storage for radio communications: Description and design methodology

    NASA Technical Reports Server (NTRS)

    Chapman, C. P.; Chapman, P. D.; Lewison, A. H.

    1982-01-01

    A low power photovoltaic system was constructed with approximately 500 amp hours of battery energy storage to provide power to an emergency amateur radio communications center. The system can power the communications center for about 72 hours of continuous nonsun operation. Complete construction details and a design methodology algorithm are given with abundant engineering data and adequate theory to allow similar systems to be constructed, scaled up or down, with minimum design effort.

  9. 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.

  10. Designing Energy Efficient Communication Runtime Systems: A View from PGAS Models

    SciTech Connect

    Vishnu, Abhinav; Song, Shuaiwen; Marquez, Andres; Barker, Kevin J.; Kerbyson, Darren J.; Cameron, Kirk; Balaji, Pavan

    2011-10-06

    As the march to the Exascale computing gains momentum, energy consumption of supercomputers has emerged to be the critical roadblock. While architectural innovations are imperative in achieving computing of this scale, it is largely dependent on the systems software to leverage the architectural innovations. Parallel applications in many computationally intensive domains have been designed to leverage these supercomputers, with legacy two-sided communication semantics using Message Passing Interface. At the same time, Partitioned Global Address Space Models are being designed which provide global address space abstractions and one-sided communication for exploiting data locality and communication optimizations. PGAS models rely on one-sided communication runtime systems for leveraging high-speed networks to achieve best possible performance. In this paper, we present a design for Power Aware One-Sided Communication Library - PASCoL. The proposed design detects communication slack, leverages Dynamic Voltage and Frequency Scaling (DVFS) and Interrupt driven execution to exploit the detected slack for energy efficiency. We implement our design and evaluate it using synthetic benchmarks for one-sided communication primitives, Put, Get and Accumulate and uniformly non-contiguous data transfers. Our performance evaluation indicates that we can achieve significant reduction in energy consumption without performance loss on multiple one-sided communication primitives. The achieved results are close to the theoretical peak available with the experimental test bed.

  11. Integrated command, control, communication and computation system design study. Summary of tasks performed

    NASA Technical Reports Server (NTRS)

    1982-01-01

    A summary of tasks performed on an integrated command, control, communication, and computation system design study is given. The Tracking and Data Relay Satellite System command and control system study, an automated real-time operations study, and image processing work are discussed.

  12. Design of the Protocol Processor for the ROBUS-2 Communication System

    NASA Technical Reports Server (NTRS)

    Torres-Pomales, Wilfredo; Malekpour, Mahyar R.; Miner, Paul S.

    2005-01-01

    The ROBUS-2 Protocol Processor (RPP) is a custom-designed hardware component implementing the functionality of the ROBUS-2 fault-tolerant communication system. The Reliable Optical Bus (ROBUS) is the core communication system of the Scalable Processor-Independent Design for Enhanced Reliability (SPIDER), a general-purpose fault tolerant integrated modular architecture currently under development at NASA Langley Research Center. ROBUS is a time-division multiple access (TDMA) broadcast communication system with medium access control by means of time-indexed communication schedule. ROBUS-2 is a developmental version of the ROBUS providing guaranteed fault-tolerant services to the attached processing elements (PEs), in the presence of a bounded number of faults. These services include message broadcast (Byzantine Agreement), dynamic communication schedule update, time reference (clock synchronization), and distributed diagnosis (group membership). ROBUS also features fault-tolerant startup and restart capabilities. ROBUS-2 tolerates internal as well as PE faults, and incorporates a dynamic self-reconfiguration capability driven by the internal diagnostic system. ROBUS consists of RPPs connected to each other by a lower-level physical communication network. The RPP has a pipelined architecture and the design is parameterized in the behavioral and structural domains. The design of the RPP enables the bus to achieve a PE-message throughput that approaches the available bandwidth at the physical layer.

  13. Design and Performance Analysis of Downlink in Space Communications System for Lunar Exploration

    NASA Astrophysics Data System (ADS)

    Lee, Wooju; Cho, Kyongkuk; Yoon, Dongweon

    2010-03-01

    Korean government made clear that it would make efforts to carry out full-fledged research into space exploration with the aim of developing a Lunar Orbiter (LO) from 2017 to 2020 in the detailed implement guidance of the space development project established in 2007 (Lee 2009). To make the plan realized, basic researches into a space communication link are essential (Kim et al. 2009). However, local researches in Korea were focused on the near-earth satellite communication links and the researches on the deep space communications were hardly founded. This paper designs and analyzes the downlink between a LO and an Earth Station (ES) in space communications system for lunar exploration, and suggests requirements for the communication link design with conforming to international recommendations. In general, among the losses in the calculation of a space communication link budget between the LO and the ES, the largest one is the free space loss comes from the distance between the earth and the moon. Furthermore, an accurate link model should be made up in order to analyze the performance in a more accurate way, with all the other elements influencing on signal quality. In this paper, we design the model of a space communications system considering almost all elements to affect the downlink performance of the space communications system between the LO and the ES, based on detailed requirements by CCSDS (the Consultative Committee for Space Data Systems, 2007), and verify the results with reference to the foreign operation cases of NASA (National Aeronautics and Space Administration) DSN (Deep Space Network) (Slobin 2006, Sniffin 2002, 2008). According to the CCSDS, we assume that the communication links have the line of sight path between the LO and the ES for S, X, Ku, and Ka bands, and an uncoded OQPSK signal is considered for a telemetry transmission. Also, a required target BER (Bit Error Rate) in the downlink space communications systems is assumed to be 10^5. We

  14. Design of oil pipeline leak detection and communication system based on optical fiber technology

    NASA Astrophysics Data System (ADS)

    Tu, Yaqing; Chen, Huabo

    1999-08-01

    The integrity of oil pipeline is always a major concern of operators. Pipeline leak not only leads to loss of oil, but pollutes environment. A new pipeline leak detection and communication system based on optical fiber technology to ensure the pipeline reliability is presented. Combined direct leak detection method with an indirect one, the system will greatly reduce the rate of false alarm. According, to the practical features of oil pipeline,the pipeline communication system is designed employing the state-of-the-art optic fiber communication technology. The system has such feature as high location accuracy of leak detection, good real-time characteristic, etc. which overcomes the disadvantages of traditional leak detection methods and communication system effectively.

  15. Design and implementation of a microprocessor controlled integrated voice communications system

    NASA Astrophysics Data System (ADS)

    Stevens, C. J.; Moore, T. R.

    The effects of implementation of microprocessors and LSI circuits to produce a new generation of integrated voice communications systems (IVCS) are explored. The IVCS includes a headset as a loudspeaker and function keys for communications over various facilities. The design concept integrates radio and telephone communications channels, push button circuit selection, push-to-talk switches, a loudspeaker in the console, and intercom dialing capability. No single component failure is permitted to make the entire system inoperative, and hard-wiring is eliminated. Additionally, rewiring is ameliorated by the flexible nature of LSI. Block diagrams are provided for the circuitry of the system, which is intended for use in ATC, air defense networks, C3 applications, public safety, police and fire systems, and corporate communications.

  16. Automatic antenna switching design for Extra Vehicular Activity (EVA) communication system

    NASA Technical Reports Server (NTRS)

    Randhawa, Manjit S.

    1987-01-01

    An Extra Vehicular Activity (EVA) crewmember had two-way communications with the space station in the Ku-band frequency (12 to 18 GHz). The maximum range of the EVA communications link with the space station is approximately one kilometer for nominal values for transmitter power, antenna gains, and receiver noise figure. The EVA Communications System, that will continue to function regardless of the astronaut's position and orientation, requires an antenna system that has full spherical coverage. Three or more antennas that can be flush mounted on the astronaut's space suit (EMU) and/or his propulsive backpack (MMU), will be needed to provide the desired coverage. As the astronaut moves in the space station, the signal received by a given EVA antenna changes. An automatic antenna switching system is needed that will switch the communication system to the antenna with the largest signal strength. A design for automatic antenna switching is presented and discussed.

  17. Radiology information systems, picture archiving and communication systems, teleradiology--overview and design criteria.

    PubMed

    Roberson, G H; Shieh, Y Y

    1998-11-01

    Information technology (IT), long taken for granted in commercial settings, is now being utilized for health-care applications. Medical imaging has lagged comparatively due to the extremely vast data content of each frame; thus, the requirement for expensive high-end components. Further, IT in radiology has evolved from two distinctly separate camps--information systems, known as RIS (radiology information systems) and PACS (picture archiving and communications systems). Both RIS and PACS applications have migrated to the PC environment, enabling cost-effective implementation, but from two backgrounds: RIS from vendors using conventional information systems platforms and products, and PACS from radiographic film and modality vendors. The radiology department at Texas Tech University has assembled a seamlessly integrated, enterprise-wide RIS/PACS/teleradiology intranet. The design criteria include user-friendliness, flexibility to respond to changing needs, and open modular architecture to assure interoperability, cost-effectiveness, and future-proofing of investment. Since no single venor could provide an integrated system meeting our specifications, we decided to assume the burden of constructing our own system. As the system integrator, we embrace open architecture, thus enabling the incorporation of industry-standard-compliant, COTS (commercially off the shelf) products as modules. Microsoft Windows NT operating system, Visual C++ programming language, TCP/IP (transmission control protocol/internetworking protocol), relational SQL (structured query language) database, ODBC (open database connectivity), HL-7 (health level seven) and DICOM (digital imaging and communications in medicine) interfaces are utilized. The usage of COTS components reduces the cost to very affordable levels. With this approach, any module in our system can be replaced when outmoded, without affecting other modules in our system, making it truly future-proof. Construction and evolution of

  18. The design principles of edutainment system for autistic children with communication difficulties

    NASA Astrophysics Data System (ADS)

    Hussain, Azham; Abdullah, Adil; Husni, Husniza

    2016-08-01

    Approximately 50% of all individuals with Autism have difficulties in developing functional language owing to communication deterioration. Mobile devices with installed educational games help these individuals feel more comfortable and relaxed doing such activities. Although numerous mobile applications are available for individuals with Autism, they are difficult to use; particularly in terms of user-interface design. From the analysis of existing apps for autistic children, an app design principles are proposed based on interaction design (IxD), that would fulfil the users' requirements in a better manner. Five applications were involved in this analysis. The analysis identified fifteen suggestions for the design principles. These recommendations are offered by this paper towards designing and developing a prototype app for autistic children. This paper introduces an edutainment-system design principle formulated to help develop the communication skills of children with Autism-spectrum disorders.

  19. System design for the digitally implemented communications experiment /DICE/. [Communications Technology Satellite television for teleconferencing

    NASA Technical Reports Server (NTRS)

    Gatfield, A. G.; Suyderhoud, H. G.; Wolejsza, C. J., Jr.

    1977-01-01

    Full-duplex digital television providing a teleconference capability is to be evaluated in an experimental program utilizing the Communications Technology Satellite. The digitally implemented communications experiment employs a QPSK modulator-demodulator capable of operation over a wide range of bit rates. In addition to simultaneous data transmission (used for digital high-speed facsimiles and remote computer terminals), voice transmission through four-to-one compression will be studied.

  20. Baseband-processed SS-TDMA communication system architecture and design concepts

    NASA Technical Reports Server (NTRS)

    Attwood, S.; Sabourin, D.

    1982-01-01

    The architecture and system design for a commercial satellite communications system planned for the 1990's was developed by Motorola for NASA's Lewis Research Center. The system provides data communications between individual users via trunking and customer premises service terminals utilizing a central switching satellite operating in a time-division multiple-access (TDMA) mode. The major elements of the design incorporating baseband processing include: demand-assigned multiple access reservation protocol, spectral utilization, system synchronization, modulation technique and forward error control implementation. Motorola's baseband processor design, which is being proven in a proof-of-concept advanced technology development, will perform data regeneration and message routing for individual users on-board the spacecraft.

  1. Baseband-processed SS-TDMA communication system architecture and design concepts

    NASA Astrophysics Data System (ADS)

    Attwood, S.; Sabourin, D.

    The architecture and system design for a commercial satellite communications system planned for the 1990's was developed by Motorola for NASA's Lewis Research Center. The system provides data communications between individual users via trunking and customer premises service terminals utilizing a central switching satellite operating in a time-division multiple-access (TDMA) mode. The major elements of the design incorporating baseband processing include: demand-assigned multiple access reservation protocol, spectral utilization, system synchronization, modulation technique and forward error control implementation. Motorola's baseband processor design, which is being proven in a proof-of-concept advanced technology development, will perform data regeneration and message routing for individual users on-board the spacecraft.

  2. A Design of the Signal Processing Hardware Platform for Communication Systems

    NASA Astrophysics Data System (ADS)

    Lee, Byung Wook; Cho, Sung Ho

    In this letter, an efficient hardware platform for the digital signal processing for OFDM communication systems is presented. The hardware platform consists of a single FPGA having 900K gates, two DSPs with maximum 8,000 MIPS at 1GHz clock, 2-channel ADC and DAC supporting maximum 125MHz sampling rate, and flexible data bus architecture, so that a wide variety of baseband signal processing algorithms for practical OFDM communication systems may be implemented and tested. The IEEE 802.16d software modem is also presented in order to verify the effectiveness and usefulness of the designed platform.

  3. Observer design for compensation of network-induced delays in integrated communication and control systems

    NASA Technical Reports Server (NTRS)

    Luck, R.; Ray, A.

    1988-01-01

    A method for compensating the effects of network-induced delays in integrated communication and control systems (ICCS) is proposed, and a finite-dimensional time-invariant ICCS model is developed. The problem of analyzing systems with time-varying and stochastic delays is circumvented by the application of a deterministic observer. For the case of controller-to-actuator delays, the observed design must rely on an extended model which represents the delays as additional states.

  4. Shuttle orbiter Ku-band radar/communications system design evaluation

    NASA Technical Reports Server (NTRS)

    Dodds, J.; Holmes, J.; Huth, G. K.; Iwasaki, R.; Maronde, R.; Polydoros, A.; Weber, C.; Broad, P.

    1980-01-01

    Tasks performed in an examination and critique of a Ku-band radar communications system for the shuttle orbiter are reported. Topics cover: (1) Ku-band high gain antenna/widebeam horn design evaluation; (2) evaluation of the Ku-band SPA and EA-1 LRU software; (3) system test evaluation; (4) critical design review and development test evaluation; (5) Ku-band bent pipe channel performance evaluation; (6) Ku-band LRU interchangeability analysis; and (7) deliverable test equipment evaluation. Where discrepancies were found, modifications and improvements to the Ku-band system and the associated test procedures are suggested.

  5. Statistical Risk Estimation for Communication System Design: Results of the HETE-2 Test Case

    NASA Astrophysics Data System (ADS)

    Babuscia, A.; Cheung, K.-M.

    2014-05-01

    The Statistical Risk Estimation (SRE) technique described in this article is a methodology to quantify the likelihood that the major design drivers of mass and power of a space system meet the spacecraft and mission requirements and constraints through the design and development lifecycle. The SRE approach addresses the long-standing challenges of small sample size and unclear evaluation path of a space system, and uses a combination of historical data and expert opinions to estimate risk. Although the methodology is applicable to the entire spacecraft, this article is focused on a specific subsystem: the communication subsystem. Using this approach, the communication system designers will be able to evaluate and to compare different communication architectures in a risk trade-off perspective. SRE was introduced in two previous papers. This article aims to present additional results of the methodology by adding a new test case from a university mission, the High-Energy Transient Experiment (HETE)-2. The results illustrate the application of SRE to estimate the risks of exceeding constraints in mass and power, hence providing crucial risk information to support a project's decision on requirements rescope and/or system redesign.

  6. Mit castor satellite: Design, implementation, and testing of the communication system

    NASA Astrophysics Data System (ADS)

    Babuscia, Alessandra; McCormack, Matthew Michael; Munoz, Michael; Parra, Spencer; Miller, David W.

    2012-12-01

    Cathode Anode Satellite Thruster for Orbital Reposition (CASTOR) is an orbital manoeuvre and transfer micro-satellite bus developed at MIT Space System Laboratory. The technical objective of the mission is achieving 1 km/s of delta-V over a 1 year mission in Low Earth Orbit (LEO). This will be accomplished using a novel electric propulsion system, the Diverging Cusped Field Thruster (DCFT), which enables high efficiency orbital changes of the ESPA-ring class satellite. CASTOR is capable of improving rapid access to space capabilities by providing an orbital transfer platform with a very high performance to mass ratio, thus greatly reducing launch costs and allowing for highly efficient orbital manoeuvre. Furthermore, CASTOR is highly scalable and modular, allowing it to be adapted to a wide range of scales and applications. CASTOR is developed as part of the University Nanosatellite Program (UNP) funded by Air Force Research Laboratory (AFRL). In order to accomplish CASTOR mission objective, a highly optimized, scalable, light weight, and low cost communication system needed to be developed. These constraints imply the development of trade studies to select the final communication system architecture able to maximize the amount of data transmitted, while guaranteeing reliability, redundancy and limited mass, power consumption, and cost. A special attention is also required to guarantee a reliable communication system in cases of tumbling, or in case of strong Doppler shift which is inevitable due to the high delta-V capabilities of the vehicle. In order to accomplish all the mission requirements, different features have been introduced in the design of the communication system for this mission. Specifically, customized patch antennas have been realized, and a customized communication protocol has been designed and implemented. The communication subsystem has been validated through an intense testing campaign which included software tests in the laboratory, hardware

  7. Observer-based controller design for networked control systems with sensor quantisation and random communication delay

    NASA Astrophysics Data System (ADS)

    Liu, Ming; You, Jia

    2012-10-01

    This article addresses the study of observer-based controller design for network-based control systems in the presence of output quantisation and random communication delay simultaneously. In the communication channel, the output measurement are quantised before transmission, and two kinds of network-induced delays are taken into account simultaneously: (i) random delay from sensor to controller and (ii) random delay from controller to actuator. These two types of random delays are modelled as two independent Bernoulli distributed white sequences. The observer-based controller is synthesised to stabilise the networked closed-loop system in the sense of stochastic stability. Sufficient conditions for the existence of the controller are provided by stochastic Lyapunov method. An illustrative numerical example is employed to demonstrate the applicability and flexibility of the proposed design strategy.

  8. Design considerations for a fiber optic communications network for power systems

    SciTech Connect

    Kirkham, H.; Johnston, A.R.; Allen, G.D.

    1993-08-01

    The design of a fiber optic communication network for monitoring and control in power systems is discussed. It is shown that by appropriate choice of protocols, a fault-tolerant system can be built that operates in any arbitrary configuration. Since the network is based on fiber optics, it can be made fast enough for substation monitoring and control. In this application, a relatively small number of cables is required to implement a high reliability system. The network can also be used for distribution automation. In this application the network is required to reach all parts of the power system, and the fiber cable itself becomes a significant fraction of the cost of communications. However, since many applications can be supported at once, the cost per function can be reasonable.

  9. Air traffic management system design using satellite based geo-positioning and communications assets

    NASA Technical Reports Server (NTRS)

    Horkin, Phil

    1995-01-01

    The current FAA and ICAO FANS vision of Air Traffic Management will transition the functions of Communications, Navigation, and Surveillance to satellite based assets in the 21st century. Fundamental to widespread acceptance of this vision is a geo-positioning system that can provide worldwide access with best case differential GPS performance, but without the associated problems. A robust communications capability linking-up aircraft and towers to meet the voice and data requirements is also essential. The current GPS constellation does not provide continuous global coverage with a sufficient number of satellites to meet the precision landing requirements as set by the world community. Periodic loss of the minimum number of satellites in view creates an integrity problem, which prevents GPS from becoming the primary system for navigation. Furthermore, there is reluctance on the part of many countries to depend on assets like GPS and GLONASS which are controlled by military communities. This paper addresses these concerns and provides a system solving the key issues associated with navigation, automatic dependent surveillance, and flexible communications. It contains an independent GPS-like navigation system with 27 satellites providing global coverage with a minimum of six in view at all times. Robust communications is provided by a network of TDMA/FDMA communications payloads contained on these satellites. This network can support simultaneous communications for up to 30,000 links, nearly enough to simultaneously support three times the current global fleet of jumbo air passenger aircraft. All of the required hardware is directly traceable to existing designs.

  10. Optimum Co-Design for Spectrum Sharing between Matrix Completion Based MIMO Radars and a MIMO Communication System

    NASA Astrophysics Data System (ADS)

    Li, Bo; Petropulu, Athina P.; Trappe, Wade

    2016-09-01

    Recently proposed multiple input multiple output radars based on matrix completion (MIMO-MC) employ sparse sampling to reduce the amount of data that need to be forwarded to the radar fusion center, and as such enable savings in communication power and bandwidth. This paper proposes designs that optimize the sharing of spectrum between a MIMO-MC radar and a communication system, so that the latter interferes minimally with the former. First, the communication system transmit covariance matrix is designed to minimize the effective interference power (EIP) to the radar receiver, while maintaining certain average capacity and transmit power for the communication system. Two approaches are proposed, namely a noncooperative and a cooperative approach, with the latter being applicable when the radar sampling scheme is known at the communication system. Second, a joint design of the communication transmit covariance matrix and the MIMO-MC radar sampling scheme is proposed, which achieves even further EIP reduction.

  11. Design of visible light communication system for maintaining uniform data rate

    NASA Astrophysics Data System (ADS)

    Sung, Jiun-Yu; Lin, Wan-Feng; Wu, Yu-Fu; Chow, Chi-Wai; Yeh, Chien-Hung

    2014-09-01

    Light-emitting diode (LED) is gradually replacing the fluorescent lamp for lighting. Higher modulation bandwidth of LEDs makes the additional application of visible light communication (VLC) possible. Every location of a VLC system should be provided by equal data rate for smooth communication. However, locations away from the LED lamp have less power. These low-power locations have lower signal-to-noise ratio (SNR); and hence lower data rate can be achieved. For achieving high capacity VLC, strategies should be adequately provided to mitigate this problem. Moreover, for some real-time continuous applications, such as video and voice, latency reduction plan should also be considered. In this paper, an orthogonal frequency-division multiplexing access (OFDMA) based system was proposed to solve the above problem. Because we do not use time-division multiplexing access (TDMA) based system, the latency issue can be reduced. The OFDMA based system is also beneficial for large scale operation because the user bandwidth is not reduced by TDM mechanism. Signal-to-noise-plus-interference ratio (SNIR) distribution of the VLC system is designed to ensure uniform and optimal system capacity. Discrete multi-tone (DMT) is used for this VLC system. The DMT subcarriers are bit-loaded depending on the LED frequency response. More subcarriers are allocated for communication at low SNIR locations. Hence, nearly equal data rate can be provided everywhere. Demonstration of 17 Mb/s/LED data rate was provided.

  12. Digital communication systems

    NASA Astrophysics Data System (ADS)

    Peebles, Peyton Z., Jr.

    The fundamental principles of digital communication and the design of practical digital communication systems are explored in an introductory textbook for senior and graduate students of electrical engineering. Chapters are devoted to sampling principles, baseband digital waveforms, baseband digital systems, bandpass binary digital systems, and M-ary digital systems. Deterministic signals, networks, and random-signal theory are reviewed in extensive appendices, and graphs, flow charts, diagrams, and problems are provided.

  13. Nonverbal Communication Systems.

    ERIC Educational Resources Information Center

    Leathers, Dale G.

    This book was designed to meet five specific criteria which allow development of a course parallel to the treatment of the book's subject matter, active student involvement in testing and developing their own nonverbal communication capacities, delineation and analysis of the functional capacity of different nonverbal communication systems, an…

  14. Design of Radio Frequency Link in Automatic Test System for Multimode Mobile Communication Base Station

    NASA Astrophysics Data System (ADS)

    Zhang, Weipeng

    2015-12-01

    A modularized design for the radio frequency (RF) link in automatic test system of multimode mobile communication base station is presented, considering also the characteristics of wireless communication indices and composition of signals of base stations. The test link is divided into general module, time division duplex (TDD) module, module of spurious noise filter, module of downlink intermodulation, module of uplink intermodulation and uplink block module. The composition of modules and link functions are defined, and the interfaces of the general module and the module of spurious noise filter are described. Finally, the estimated gain budget of the test link is presented. It is verified by experiments that the system is reliable and the test efficiency is improved.

  15. The design and implementation of a picture archiving and communication system for pediatric radiology

    SciTech Connect

    Taira, R.K.

    1988-01-01

    The methods for viewing and managing radiological images have remained relatively unchanged for several decades. Inefficiencies in the current system result in mismanaged films and delays in medical reporting. This study presents the design, implementation and evaluation of a novel picture archiving and communication system (PACS) within the pediatric radiology section of a 500-bed teaching hospital. The system is composed of an integrated network of computerized devices used to digitally acquire, store, manage, display, and process radiological images. The key PACS issues covered in this dissertation include: (a) definition of data, processing, and user requirements, (b) software and hardware integration of various radiological imaging subsystems, (c) design of an efficient database structure which manages several thousand megabytes of information, (d) system performance tuning, (e) development of an acceptable user interface to a six-monitor 512 {times} 512 line CRT workstation, and (f) clinical evaluation.

  16. An interdisciplinary team communication framework and its application to healthcare 'e-teams' systems design

    PubMed Central

    2009-01-01

    Background There are few studies that examine the processes that interdisciplinary teams engage in and how we can design health information systems (HIS) to support those team processes. This was an exploratory study with two purposes: (1) To develop a framework for interdisciplinary team communication based on structures, processes and outcomes that were identified as having occurred during weekly team meetings. (2) To use the framework to guide 'e-teams' HIS design to support interdisciplinary team meeting communication. Methods An ethnographic approach was used to collect data on two interdisciplinary teams. Qualitative content analysis was used to analyze the data according to structures, processes and outcomes. Results We present details for team meta-concepts of structures, processes and outcomes and the concepts and sub concepts within each meta-concept. We also provide an exploratory framework for interdisciplinary team communication and describe how the framework can guide HIS design to support 'e-teams'. Conclusion The structures, processes and outcomes that describe interdisciplinary teams are complex and often occur in a non-linear fashion. Electronic data support, process facilitation and team video conferencing are three HIS tools that can enhance team function. PMID:19754966

  17. Designing Communication and Learning Environments.

    ERIC Educational Resources Information Center

    Gayeski, Diane M., Ed.

    Designing and remodeling educational facilities are becoming more complex with options that include computer-based collaboration, classrooms with multimedia podiums, conference centers, and workplaces with desktop communication systems. This book provides a collection of articles that address educational facility design categorized in the…

  18. Spacecraft flight control system design selection process for a geostationary communication satellite

    NASA Technical Reports Server (NTRS)

    Barret, C.

    1992-01-01

    The Earth's first artificial satellite, Sputnik 1, slowly tumbled in orbit. The first U.S. satellite, Explorer 1, also tumbled out of control. Now, as we launch the Mars observer and the Cassini spacecraft, stability and control have become higher priorities. The flight control system design selection process is reviewed using as an example a geostationary communication satellite which is to have a life expectancy of 10 to 14 years. Disturbance torques including aerodynamic, magnetic, gravity gradient, solar, micrometeorite, debris, collision, and internal torques are assessed to quantify the disturbance environment so that the required compensating torque can be determined. Then control torque options, including passive versus active, momentum control, bias momentum, spin stabilization, dual spin, gravity gradient, magnetic, reaction wheels, control moment gyros, nutation dampers, inertia augmentation techniques, three-axis control, reactions control system (RCS), and RCS sizing, are considered. A flight control system design is then selected and preliminary stability criteria are met by the control gains selection.

  19. Design of an anti-Rician-fading modem for mobile satellite communication systems

    NASA Technical Reports Server (NTRS)

    Kojima, Toshiharu; Ishizu, Fumio; Miyake, Makoto; Murakami, Keishi; Fujino, Tadashi

    1995-01-01

    To design a demodulator applicable to mobile satellite communication systems using differential phase shift keying modulation, we have developed key technologies including an anti-Rician-fading demodulation scheme, an initial acquisition scheme, automatic gain control (AGC), automatic frequency control (AFC), and bit timing recovery (BTR). Using these technologies, we have developed one-chip digital signal processor (DSP) modem for mobile terminal, which is compact, of light weight, and of low power consumption. Results of performance test show that the developed DSP modem achieves good performance in terms of bit error ratio in mobile satellite communication environment, i.e., Rician fading channel. It is also shown that the initial acquisition scheme acquires received signal rapidly even if the carrier-to-noise power ratio (CNR) of the received signal is considerably low.

  20. Design and Implementation of Flexible Web BBS for Class Communication Support System

    NASA Astrophysics Data System (ADS)

    Furukawa, Tatsuya; Fukumoto, Hisao; Nakashima, Nobuhiro; Ohchi, Masashi

    When a student has some questions on a class subject, he should ask questions in his class. However, the student, who cannot ask the question in the class, has to go to the teacher to ask questions after hours. In such a case, it is the problem that profitable information discussed between the teacher and the student by questioning will not spread over all students. Therefore, we have designed and implemented the system which provides smooth communication and sharing information after hours. In this paper, we describes the further improvement on enriched expressions and the usability on Web.

  1. Characterization of interfade duration for satellite communication systems design and optimization in a temperate climate

    NASA Astrophysics Data System (ADS)

    Jorge, Flávio; Riva, Carlo; Rocha, Armando

    2016-03-01

    The characterization of the fade dynamics on Earth-satellite links is an important subject when designing the so called fade mitigation techniques that contribute to the proper reliability of the satellite communication systems and the customers' quality of service (QoS). The interfade duration, defined as the period between two consecutive fade events, has been only poorly analyzed using limited data sets, but its complete characterization would enable the design and optimization of the satellite communication systems by estimating the system requirements to recover in time before the next propagation impairment. Depending on this analysis, several actions can be taken ensuring the service maintenance. In this paper we present for the first time a detailed and comprehensive analysis of the interfade events statistical properties based on 9 years of in-excess attenuation measurements at Ka band (19.7 GHz) with very high availability that is required to build a reliable data set mainly for the longer interfade duration events. The number of years necessary to reach the statistical stability of interfade duration is also evaluated for the first time, providing a reference when accessing the relevance of the results published in the past. The study is carried out in Aveiro, Portugal, which is conditioned by temperate Mediterranean climate with Oceanic influences.

  2. 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.

  3. Experience and design recommendations for picture archiving and communication systems in the surgical setting.

    PubMed

    Pomerantz, S M; Siegel, E L; Protopapas, Z; Reiner, B I; Pickar, E R

    1996-08-01

    An analysis of the efficacy of a picture archiving and communication system (PACS) in the surgical domain was undertaken at the Baltimore Veterans Affairs Medical Center. Interviews with surgeons and staff were conducted and supplemented by direct radiologist observation in the operating room (OR) and surgical outpatient clinic to determine patterns of routine clinical PACS use, levels of satisfaction both within and outside of the OR, and perceptions of the relative efficacy of the system in comparison to film. These data as well as suggestions from the surgical staff members were used to make recommendations for specific modifications in PACS design and operation to improve the current system and to help prescribe design improvements for future PAC systems. A high level of satisfaction with the system was found and the use of PACS was favored over film by a majority of surgeons and their staff. Findings of this study suggest that the design of a hospital-wide PAC system must have the flexibility to accommodate the specific requirements of a wide variety of end-users in their unique hospital environments. PMID:8854262

  4. Design and implementation of omni-directional light source and receiving system used in underwater wireless optical communication

    NASA Astrophysics Data System (ADS)

    Rao, Jionghui; Yao, Wenming; Chen, Nannan

    2013-08-01

    Underwater wireless optical communication is a communication mode which uses light as an information carrier and water as transmission medium. As a result of the inherent characteristics of the light waves, underwater wireless optical communication has the advantages of high transmission rate, good security, and strong anti-interference ability. It is suitable for high-speed, short-range communication between underwater mobile vehicles. Underwater optical wireless communication system designed in this paper is composed of the omni-directional communication light source and the receiving system. In the omni-directional communication light source, the laser beams with small divergence angle of 532nm wavelength produced by modulated laser are expanded through a combination refraction-reflection solid and then obtain more than 2π space divergence angle. The paper use TRACEPRO simulation tool to help design a combination solid composed of the lens, conical reflector and parabolic reflector, and test in the air and underwater, the result shows that the effect is fine. Unlike in the air, light attenuation is heavy in the water and a large range of variations in light intensity at different distances appear during underwater optical communication. In order to overcome this problem, the paper use a small photomultiplier as the detection device, design the receiving system using the automatic gain control technique. Underwater wireless optical communication system designed in this paper has the characteristics of small size, low power dissipation and the omni-directional communication function, it is suitable for application in the UUV, AUV, Swimmer Delivery Vehicle (SDV) and other underwater mobile platform, it realizes point-to-point communications and point-to-multipoint communications.

  5. A Measurement and Power Line Communication System Design for Renewable Smart Grids

    NASA Astrophysics Data System (ADS)

    Kabalci, E.; Kabalci, Y.

    2013-10-01

    The data communication over the electric power lines can be managed easily and economically since the grid connections are already spread around all over the world. This paper investigates the applicability of Power Line Communication (PLC) in an energy generation system that is based on photovoltaic (PV) panels with the modeling study in Matlab/Simulink. The Simulink model covers the designed PV panels, boost converter with Perturb and Observe (P&O) control algorithm, full bridge inverter, and the binary phase shift keying (BPSK) modem that is utilized to transfer the measured data over the power lines. This study proposes a novel method to use the electrical power lines not only for carrying the line voltage but also to transmit the measurements of the renewable energy generation plants. Hence, it is aimed at minimizing the additional monitoring costs such as SCADA, Ethernet-based or GSM based systems by using the proposed technique. Although this study is performed with solar power plants, the proposed model can be applied to other renewable generation systems. Consequently, the usage of the proposed technique instead of SCADA or Ethernet-based systems eliminates additional monitoring costs.

  6. Alternative Communication Network Designs for an Operational Plato IV CAI System.

    ERIC Educational Resources Information Center

    Morley, Robert E., Jr.; Eastwood, Lester F., Jr.

    Alternative communication networks for the dissemination of PLATO IV computer aided instruction were designed and comparative cost estimates were made for leased telephone lines, satellite communications, UHF TV, and low-power microwave radio. Costs per student contact hour were computed on the basis of student population density in public schools…

  7. The design and networking of dynamic satellite constellations for global mobile communication systems

    NASA Technical Reports Server (NTRS)

    Cullen, Cionaith J.; Benedicto, Xavier; Tafazolli, Rahim; Evans, Barry

    1993-01-01

    Various design factors for mobile satellite systems, whose aim is to provide worldwide voice and data communications to users with hand-held terminals, are examined. Two network segments are identified - the ground segment (GS) and the space segment (SS) - and are seen to be highly dependent on each other. The overall architecture must therefore be adapted to both of these segments, rather than each being optimized according to its own criteria. Terrestrial networks are grouped and called the terrestrial segment (TS). In the SS, of fundamental importance is the constellation altitude. The effect of the altitude on decisions such as constellation design choice and on network aspects like call handover statistics are fundamental. Orbit resonance is introduced and referred to throughout. It is specifically examined for its useful properties relating to GS/SS connectivities.

  8. AMPA experimental communications systems

    NASA Technical Reports Server (NTRS)

    Beckerman, D.; Fass, S.; Keon, T.; Sielman, P.

    1982-01-01

    The program was conducted to demonstrate the satellite communication advantages of Adaptive Phased Array Technology. A laboratory based experiment was designed and implemented to demonstrate a low earth orbit satellite communications system. Using a 32 element, L-band phased array augmented with 4 sets of weights (2 for reception and 2 for transmission) a high speed digital processing system and operating against multiple user terminals and interferers, the AMPA system demonstrated: communications with austere user terminals, frequency reuse, communications in the face of interference, and geolocation. The program and experiment objectives are described, the system hardware and software/firmware are defined, and the test performed and the resultant test data are presented.

  9. Design and realization of FEC-based RS code in the atmospheric laser communication system

    NASA Astrophysics Data System (ADS)

    Chang, Limin; Song, Lu; Zhang, Lijing

    2008-12-01

    The RS(Reed-Solomon) code is an important linear block and used for solving the problem of serious distortion and BER(Bit Error Rate) in the atmospheric laser communication system. RS (255,223) code are selected as channel code. Meanwhile, technologies for the laser communication system such as encode, interleaving, decode have been discussed in details. In this paper, an improved RiBM algorithm is adopted in the key equations solver of decoding algorithm. In the Forney's algorithm, inversion circuit in finite field is adopted. Then, division operation in the error value is realization by subtraction of power exponent. As a result, the whole decoding chip obtains the optimization in the speed and the usage resources. The hardware structure design and algorithms program have been finished on FPGA according to CCSDS specification. The BER performance verification has been applied in Visual C language. The experiment results show that coded data can obtain SNR (Signal-to-Noise Ratio) gain of 3-5dB when BER requirement of 10-5 is satisfied in this system.

  10. The design, test, and application of the front end in 0.3THz wireless communication systems

    NASA Astrophysics Data System (ADS)

    Wang, Hanqing; Yuan, Weiwen; Zhang, Bo; Li, Huiyuan; Zhang, Zhuo; Yang, Xiaojie; Shi, Weixun

    2015-11-01

    Designed for space application, the paper presents the design, test and application of the front end in 0.3THz wireless communication. After test and fabrication, the terahertz wireless system is completed and indicates that HD video signals have been transmitted over a distance of 14m at the data rate of 1.5Gbps. The study shows the overall course of the test and application of the front end in wireless communication.

  11. Design and implementation of receiver system for a wireless infrared communication link

    NASA Astrophysics Data System (ADS)

    Jiang, Lijun; Lee, New Wei; Venkateswarlu, Ronda

    2001-10-01

    This paper reports on the design considerations and implementations of construction of a receiver system for an infrared communication link using Light-Emitting-Diodes (LEDs). System configuration is non-directed line of sight (LOS) with single element receiver. The speed of the system constructed is 20 MHz (40 Mbps for on-off keying). In our design, the receiver consists of a multi-channel photo-detector array followed by multi-channels transimpedance amplifiers, a summer circuit for combining signals, low-pass filters(LPF) and high pass filters(HPF), and auto-gain control unit(AGC). The spectral match between photodiode and LED, looking angle of photodiode, rise time consideration of the photodiode, trade-off between transit rise time and photodiode effective area, etc, are also be discussed . A receiver module of speed response up to 20 MHz has been successfully constructed and the system is capable of receiving optical signal at a height of 2 m from the ceiling with coverage of a cell of 4 m in diameter.

  12. VLSI design of turbo decoder for integrated communication system on a chip applications

    NASA Technical Reports Server (NTRS)

    Fang, Wai-Chi; Sethuram, Ashwin; Belevi, Kemal

    2003-01-01

    A high-throughput low-power turbo decoder core has been developed for integrated communication system applications such as satellite communications, wireless LAN, digital TV, cable modem, Digital Video Broadcast (DVB), and xDSL systems. The turbo decoder is based on convolutional constituent codes, which outperform all other Forward Error Correction techniques. This turbo decoder core is parameterizable and can be modified easily to fit any size for advanced communication system-on-chip products. The turbo decoder core provides Forward Error Correction of up to 15 Mbits/sec on a 0.13-micron CMOS FPGA prototyping chip at a power of 0.1 watts.

  13. Design and Performance Evaluation of a UWB Communication and Tracking System for Mini-AERCam

    NASA Technical Reports Server (NTRS)

    Barton, Richard J.

    2005-01-01

    NASA Johnson Space Center (JSC) is developing a low-volume, low-mass, robotic free-flying camera known as Mini-AERCam (Autonomous Extra-vehicular Robotic Camera) to assist the International Space Station (ISS) operations. Mini-AERCam is designed to provide astronauts and ground control real-time video for camera views of ISS. The system will assist ISS crewmembers and ground personnel to monitor ongoing operations and perform visual inspections of exterior ISS components without requiring extravehicular activity (EAV). Mini-AERCam consists of a great number of subsystems. Many institutions and companies have been involved in the R&D for this project. A Mini-AERCam ground control system has been studied at Texas A&M University [3]. The path planning and control algorithms that direct the motions of Mini-AERCam have been developed through the joint effort of Carnegie Mellon University and the Texas Robotics and Automation Center [5]. NASA JSC has designed a layered control architecture that integrates all functions of Mini-AERCam [8]. The research described in this report is part of a larger effort focused on the communication and tracking subsystem that is designed to perform three major tasks: 1. To transmit commands from ISS to Mini-AERCam for control of robotic camera motions (downlink); 2. To transmit real-time video from Mini-AERCam to ISS for inspections (uplink); 3. To track the position of Mini-AERCam for precise motion control. The ISS propagation environment is unique due to the nature of the ISS structure and multiple RF interference sources [9]. The ISS is composed of various truss segments, solar panels, thermal radiator panels, and modules for laboratories and crew accommodations. A tracking system supplemental to GPS is desirable both to improve accuracy and to eliminate the structural blockage due to the close proximity of the ISS which could at times limit the number of GPS satellites accessible to the Mini-AERCam. Ideally, the tracking system will

  14. Shuttle orbiter KU-band radar/communications system design evaluation

    NASA Technical Reports Server (NTRS)

    1979-01-01

    An expanded introduction is presented which addresses the in-depth nature of the tasks and indicates continuity of the reported effort and results with previous work and related contracts, and the two major modes of operation which exist in the Ku-band system, namely, the radar mode and the communication mode, are described. The Ku-band radar system is designed to search for a target in a designated or undesignated mode, then track the detected target, which might be cooperative (active) or passive, providing accurate, estimates of the target range, range rate, angle and angle rate to enable the orbiter to rendezvous with this target. The radar mode is described along with a summary of its predicted performance. The principal sub-unit that implements the radar function is the electronics assembly 2(EA-2). The relationship of EA-2 to the remainder of the Ku-band system is shown. A block diagram of EA-2 is presented including the main command and status signals between EA-2 and the other Ku-band units.

  15. Design of transmitter and receiver for experimental blue-green laser communication system

    NASA Astrophysics Data System (ADS)

    Xu, Tao; Chen, Xiaolu; Wen, Dong; Sun, Xiaolei

    2015-02-01

    An experimental blue-green laser communication system was developed using optical pulse position modulation (PPM) to study the feasibility of high-rate underwater communication among submerged objects. As a primary optical modulation means, PPM modulation is reviewed firstly. By comparison with other means, the conclusion was drawn that PPM has lower power requirement and it is a near optimal modulation for background-limited optical communications. For establishing laser beam propagating through the channel with modulated information through different pulse positions from the transmitter to the receiver, the transmitter subsystem and the receiver subsystem are developed and the key techniques are described separately in detail. Results indicated that the whole blue-green communication system was compact, efficient, reliable and inexpensive, and achieved a high-speed rate communication up to megabits per second and a reasonably low error rates.

  16. Design of active disturbance rejection controller for space optical communication coarse tracking system

    NASA Astrophysics Data System (ADS)

    Gu, Jian; Ai, Yong

    2015-10-01

    In order to improve the dynamic tracking performance of coarse tracking system in space optical communication, a new control method based on active disturbance rejection controller (ADRC) is proposed. Firstly, based on the structure analysis of coarse tracking system, the simplified system model was obtained, and then the extended state observer was designed to calculate state variables and spot disturbance from the input and output signals. Finally, the ADRC controller of coarse tracking system is realized with the combination of nonlinear PID controller. The simulation experimental results show that compared with the PID method, this method can significantly reduce the step response overshoot and settling time. When the target angular velocity is120mrad/s, tracking error with ADRC method is 30μrad, which decreases 85% compared with the PID method. Meanwhile the disturbance rejection bandwidth is increased by 3 times with ADRC. This method can effectively improve the dynamic tracking performance of coarse tracking and disturbance rejection degree, with no need of hardware upgrade, and is of certain reference value to the wide range and high dynamic precision photoelectric tracking system.

  17. A performance evaluation postprocessor for computer-aided design and analysis of communication systems

    NASA Technical Reports Server (NTRS)

    Tranter, W. H.

    1979-01-01

    A technique for estimating the signal-to-noise ratio at a point in a digital simulation of a communication system is described; the technique is essentially a digital realization of a technique proposed by Shepertycki (1964) for the evaluation of analog communication systems. Signals having lowpass or bandpass spectra may be used. Simulation results show the technique to be accurate over a wide range of signal-to-noise ratios.

  18. The design and research of anti-color-noise chaos M-ary communication system

    NASA Astrophysics Data System (ADS)

    Fu, Yongqing; Li, Xingyuan; Li, Yanan; Zhang, Lin

    2016-03-01

    Previously a novel chaos M-ary digital communication method based on spatiotemporal chaos Hamilton oscillator has been proposed. Without chaos synchronization circumstance, it has performance improvement in bandwidth efficiency, transmission efficiency and anti-white-noise performance compared with traditional communication method. In this paper, the channel noise influence on chaotic modulation signals and the construction problem of anti-color-noise chaotic M-ary communication system are studied. The formula of zone partition demodulator's boundary in additive white Gaussian noise is derived, besides, the problem about how to determine the boundary of zone partition demodulator in additive color noise is deeply studied; Then an approach on constructing anti-color-noise chaos M-ary communication system is proposed, in which a pre-distortion filter is added after the chaos baseband modulator in the transmitter and whitening filter is added before zone partition demodulator in the receiver. Finally, the chaos M-ary communication system based on Hamilton oscillator is constructed and simulated in different channel noise. The result shows that the proposed method in this paper can improve the anti-color-noise performance of the whole communication system compared with the former system, and it has better anti-fading and resisting disturbance performance than Quadrature Phase Shift Keying system.

  19. A knowledge-based system with learning for computer communication network design

    NASA Technical Reports Server (NTRS)

    Pierre, Samuel; Hoang, Hai Hoc; Tropper-Hausen, Evelyne

    1990-01-01

    Computer communication network design is well-known as complex and hard. For that reason, the most effective methods used to solve it are heuristic. Weaknesses of these techniques are listed and a new approach based on artificial intelligence for solving this problem is presented. This approach is particularly recommended for large packet switched communication networks, in the sense that it permits a high degree of reliability and offers a very flexible environment dealing with many relevant design parameters such as link cost, link capacity, and message delay.

  20. Design and operation of a nuclear medicine picture archiving and communication system.

    PubMed

    Brown, P H; Krishnamurthy, G T

    1990-07-01

    Construction of a new Veterans Administration Medical Center provided a unique opportunity to design and implement a state-of-the-art nuclear medicine department in a large teaching and research hospital. The new medical center allowed the acquisition of all new gamma cameras and computer systems without any historical need to patch together a system of old and new equipment. The picture archiving and communication system (PACS) was designed to link five gamma cameras to four image viewing areas, followed by digital archive on an optical disc. The gamma cameras' computers and viewing areas' computers are linked to a central networking computer in a manner that provides nine independent but digitally communicating image computers. Each nuclear medicine computer is capable of acquiring gamma camera data while possibly also performing up to three other simultaneous tasks: analysis of image data, transfer of image data from node to node, and patient database manipulation. The nine image computers each appear to the user as a digital file cabinet, containing various folders, which in turn contain patient studies. To transfer a patient study from one location to another, the user simply queues a transfer request by selecting a file drawer-folder combination for the source and destination locations. It takes only a few seconds to queue a transfer request, and the transfer is complete about a minute later without any further user intervention. A computer genie awakens during the early morning off-hours and performs housekeeping tasks, including movement of patient studies (based on date of acquisition) from active viewing folders to inactive archive folders. All scheduling, workload data, patient image reports, etc, are handled by a patient textual information database system. Patient reports and scheduling information are transmitted to the medical center's central computer where they are made readily available throughout the medical center. The PACS, in clinical use

  1. Alternative communication network designs for an operational Plato 4 CAI system

    NASA Technical Reports Server (NTRS)

    Mobley, R. E., Jr.; Eastwood, L. F., Jr.

    1975-01-01

    The cost of alternative communications networks for the dissemination of PLATO IV computer-aided instruction (CAI) was studied. Four communication techniques are compared: leased telephone lines, satellite communication, UHF TV, and low-power microwave radio. For each network design, costs per student contact hour are computed. These costs are derived as functions of student population density, a parameter which can be calculated from census data for one potential market for CAI, the public primary and secondary schools. Calculating costs in this way allows one to determine which of the four communications alternatives can serve this market least expensively for any given area in the U.S. The analysis indicates that radio distribution techniques are cost optimum over a wide range of conditions.

  2. Recipient Design in Tacit Communication

    ERIC Educational Resources Information Center

    Newman-Norlund, Sarah E.; Noordzij, Matthijs L.; Newman-Norlund, Roger D.; Volman, Inge A. C.; de Ruiter, Jan Peter; Hagoort, Peter; Toni, Ivan

    2009-01-01

    The ability to design tailored messages for specific listeners is an important aspect of human communication. The present study investigates whether a mere belief about an addressee's identity influences the generation and production of a communicative message in a novel, non-verbal communication task. Participants were made to believe they were…

  3. Effects of atmospheric turbulence on microwave and millimeter wave satellite communications systems. [attenuation statistics and antenna design

    NASA Technical Reports Server (NTRS)

    Devasirvatham, D. M. J.; Hodge, D. B.

    1981-01-01

    A model of the microwave and millimeter wave link in the presence of atmospheric turbulence is presented with emphasis on satellite communications systems. The analysis is based on standard methods of statistical theory. The results are directly usable by the design engineer.

  4. Performance evaluation using SYSTID time domain simulation. [computer-aid design and analysis for communication systems

    NASA Technical Reports Server (NTRS)

    Tranter, W. H.; Ziemer, R. E.; Fashano, M. J.

    1975-01-01

    This paper reviews the SYSTID technique for performance evaluation of communication systems using time-domain computer simulation. An example program illustrates the language. The inclusion of both Gaussian and impulse noise models make accurate simulation possible in a wide variety of environments. A very flexible postprocessor makes possible accurate and efficient performance evaluation.

  5. System design of the Pioneer Venus spacecraft. Volume 7: Communication subsystem studies

    NASA Technical Reports Server (NTRS)

    Newlands, D. M.

    1973-01-01

    Communications subsystem tradeoffs were undertaken to establish a low cost and low weight design consistent with the mission requirements. Because of the weight constraint of the Thor/Delta launched configuration, minimum weight was emphasized in determining the Thor/Delta design. In contrast, because of the greatly relaxed weight constraint of the Atlas/Centaur launched configuration, minimum cost and off the shelf hardware were emphasized and the attendant weight penalities accepted. Communication subsystem hardware elements identified for study included probe and bus antennas (CM-6, CM-17), power amplifiers (CM-10), and the large probe transponder and small probe stable oscillator required for doppler tracking (CM-11, CM-16). In addition, particular hardware problems associated with the probe high temperature and high-g environment were investigated (CM-7).

  6. Conceptual Design of the Adaptive Optics System for the Laser Communication Relay Demonstration Ground Station at Table Mountain

    NASA Technical Reports Server (NTRS)

    Roberts, Lewis C., Jr.; Page, Norman A.; Burruss, Rick S.; Truong, Tuan N.; Dew, Sharon; Troy, Mitchell

    2013-01-01

    The Laser Communication Relay Demonstration will feature a geostationary satellite communicating via optical links to multiple ground stations. The first ground station (GS-1) is the 1m OCTL telescope at Table Mountain in California. The optical link will utilize pulse position modulation (PPM) and differential phase shift keying (DPSK) protocols. The DPSK link necessitates that adaptive optics (AO) be used to relay the incoming beam into the single mode fiber that is the input of the modem. The GS-1 AO system will have two MEMS Deformable mirrors to achieve the needed actuator density and stroke limit. The AO system will sense the aberrations with a Shack-Hartmann wavefront sensor using the light from the communication link's 1.55 microns laser to close the loop. The system will operate day and night. The system's software will be based on heritage software from the Palm 3000 AO system, reducing risk and cost. The AO system is being designed to work at r(sub 0) greater than 3.3 cm (measured at 500 nm and zenith) and at elevations greater than 20deg above the horizon. In our worst case operating conditions we expect to achieve Strehl ratios of over 70% (at 1.55 microns), which should couple 57% of the light into the single mode DPSK fiber. This paper describes the conceptual design of the AO system, predicted performance and discusses some of the trades that were conducted during the design process.

  7. Mutual design of overhead transmission lines and railroad communications and signal systems. Volume 2. Appendixes. Final report

    SciTech Connect

    Taflove, A.; Umashankar, K.R.

    1983-10-01

    Objective was to develop mutual design methods and criteria for overhead ac transmission lines and adjacent railroad systems. This project has addressed basic engineering issues which govern the operation of railroad communications and signal (C and S) systems under conditions of interference from nearby transmission lines. Data and techniques have been compiled and developed to contribute to the achievement of electromagnetic compatibility in a manner that is acceptable to both the power and railroad industries.

  8. Designing Effective Persuasive Systems Utilizing the Power of Entanglement: Communication Channel, Strategy and Affect

    NASA Astrophysics Data System (ADS)

    Li, Haiqing; Chatterjee, Samir

    With rapid advances in information and communication technology, computer-mediated communication (CMC) technologies are utilizing multiple IT platforms such as email, websites, cell-phones/PDAs, social networking sites, and gaming environments. However, no studies have compared the effectiveness of a persuasive system using such alternative channels and various persuasive techniques. Moreover, how affective computing impacts the effectiveness of persuasive systems is not clear. This study proposes (1) persuasive technology channels in combination with persuasive strategies will have different persuasive effectiveness; (2) Adding positive emotion to a message that leads to a better overall user experience could increase persuasive effectiveness. The affective computing or emotion information was added to the experiment using emoticons. The initial results of a pilot study show that computer-mediated communication channels along with various persuasive strategies can affect the persuasive effectiveness to varying degrees. These results also shows that adding a positive emoticon to a message leads to a better user experience which increases the overall persuasive effectiveness of a system.

  9. Secure video communications system

    DOEpatents

    Smith, Robert L.

    1991-01-01

    A secure video communications system having at least one command network formed by a combination of subsystems. The combination of subsystems to include a video subsystem, an audio subsystem, a communications subsystem, and a control subsystem. The video communications system to be window driven and mouse operated, and having the ability to allow for secure point-to-point real-time teleconferencing.

  10. Functional design and implementation with on-line programmable technology in optical fiber communication pulse code modulation test system

    NASA Astrophysics Data System (ADS)

    Xu, Yuan; Ding, Huan; Gao, Youtang

    2010-10-01

    In order to complete the functional design in the fiber optical communication pulse code modulation test system, taking advantage of CPLD / FPGA and SOPC technology, software solutions used to design system hardware features and control functions, thereby the whole system could attain optimisation in the logic control as well as encoding and decoding functional designs on the motherboard, enabling this system fulfill the capacities varying from simple digital simulation transmission modulate to the high speed fiber optical communication network information encoding and decoding functions. Simultaneously the application of logarithmic pressure companding technique, PCM encoding and decoding system to improve the small signal quantizing SNR(Signal-to-Noise Ratio), TP3067 adopting A rate thirteen broken lines to carry on signal pressure companding. When the signal at a certain stage, the quantizing SNR is invariable(as signal receives uniform quantization in this phase, therefore the quantizing SNR drops along with signal amplititude decreasing). Test results are as follows: ideal various signal encoding and decoding system waveforms, high performance parameters , achieve the desired designing aim, a entirely new approach to realize different kinds of information encoding and decoding model building and implementation, saving development costs, improving design efficiency, satisfactory actual results, stable operation.

  11. 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.

  12. Man-Machine Interaction Design and Analysis System (MIDAS): Memory Representation and Procedural Implications for Airborne Communication Modalities

    NASA Technical Reports Server (NTRS)

    Corker, Kevin M.; Pisanich, Gregory M.; Lebacqz, Victor (Technical Monitor)

    1996-01-01

    The Man-Machine Interaction Design and Analysis System (MIDAS) has been under development for the past ten years through a joint US Army and NASA cooperative agreement. MIDAS represents multiple human operators and selected perceptual, cognitive, and physical functions of those operators as they interact with simulated systems. MIDAS has been used as an integrated predictive framework for the investigation of human/machine systems, particularly in situations with high demands on the operators. Specific examples include: nuclear power plant crew simulation, military helicopter flight crew response, and police force emergency dispatch. In recent applications to airborne systems development, MIDAS has demonstrated an ability to predict flight crew decision-making and procedural behavior when interacting with automated flight management systems and Air Traffic Control. In this paper we describe two enhancements to MIDAS. The first involves the addition of working memory in the form of an articulatory buffer for verbal communication protocols and a visuo-spatial buffer for communications via digital datalink. The second enhancement is a representation of multiple operators working as a team. This enhanced model was used to predict the performance of human flight crews and their level of compliance with commercial aviation communication procedures. We show how the data produced by MIDAS compares with flight crew performance data from full mission simulations. Finally, we discuss the use of these features to study communications issues connected with aircraft-based separation assurance.

  13. Communication, Work Systems and HRD

    ERIC Educational Resources Information Center

    Pace, R. Wayne

    2013-01-01

    Purpose: The purpose of this article is to show the foundational place that communication theory and its practice occupies in functioning work systems. Design/methodology/approach: This paper defines the word communication in terms of the creation and interpretation of displays, describes what it means to have a theoretical foundation for a…

  14. Shuttle communication and tracking systems signal design and interface compatibility analysis

    NASA Technical Reports Server (NTRS)

    1986-01-01

    Various options for the Dedicated Payload Communication Link (DPCL) were evaluated. Specific subjects addressed include: payload to DPCL power transfer in the proximity of the payload, DPCL antenna pointing considerations, and DPCL transceiver implementations which can be mounted on the deployed antenna boom. Additional analysis of the Space Telescope performance was conducted. The feasibility of using the Global Positioning System (GPS) for attitude determination and control for large spacecraft was examined. The objective of the Shuttle Orbiter Radar Test and Evaluation (SORTE) program was to quantify the Ku-band radar tracking accuracy using White Sands Missile Range (WSMR) radar and optical tracking equipment, with helicopter and balloon targets.

  15. A design proposal of a certain missile tactical command system based on Beidou satellite communication and GPS positioning techniques

    NASA Astrophysics Data System (ADS)

    Ma, Jian; Hao, Yongsheng; Miao, Jian; Zhang, Jianmao

    2007-11-01

    This paper introduced a design proposal of tactical command system that applied to a kind of anti-tank missile carriers. The tactical command system was made up of embedded computer system based on PC104 bus, Linux operating system, digital military map, Beidou satellite communication equipments and GPS positioning equipments. The geographic coordinates was measured by the GPS receiver, the positioning data, commands and information were transmitted real-time between tactical command systems, tactical command systems and command center, by the Beidou satellite communication systems. The Beidou satellite communication equipments and GPS positioning equipments were integrated to an independent module, exchanging data with embedded computer through RS232 serial ports and USB ports. The decision support system software based on information fusion, calculates positioning data, geography information and battle field information synthetically, shows the position of allies and the position of enemy on the military map, and assesses the various threats of different enemy objects, educes a situation assessment and threat assessment.

  16. Communication System and Method

    NASA Technical Reports Server (NTRS)

    Sanders, Adam M. (Inventor); Strawser, Philip A. (Inventor)

    2014-01-01

    A communication system for communicating over high-latency, low bandwidth networks includes a communications processor configured to receive a collection of data from a local system, and a transceiver in communication with the communications processor. The transceiver is configured to transmit and receive data over a network according to a plurality of communication parameters. The communications processor is configured to divide the collection of data into a plurality of data streams; assign a priority level to each of the respective data streams, where the priority level reflects the criticality of the respective data stream; and modify a communication parameter of at least one of the plurality of data streams according to the priority of the at least one data stream.

  17. Evolution of a filmless digital imaging and communications in medicine-conformant picture archiving and communications system: design issues and lessons learned over the last 3 years.

    PubMed

    Henri, C J; Cox, R D; Rubin, R; Bret, P M; Couch, G G

    1999-05-01

    This presentation describes our experience and lessons learned over the first 3 years of developing and operating a filmless picture archiving and communications system (PACS) for all computed tomography (CT), magnetic resonance (MR), ultrasound, and nuclear medicine studies in our hospital. The PACS conforms to the Digital Imaging and Communications in Medicine (DICOM) standard and includes a sophisticated Worldwide Web (WWW)-based interface to complement the regular DICOM services. The PACS has undergone many design modifications from its inception, which have addressed performance, functionality, support, and maintenance issues. The lessons we have learned through making these modifications are described here and may prove to be helpful to anyone planning to deploy a PACS of their own. PMID:10342204

  18. Design the RS(255,239) encoder and interleaving in the space laser communication system

    NASA Astrophysics Data System (ADS)

    Lang, Yue; Tong, Shou-feng

    2013-08-01

    Space laser communication is researched by more and more countries. Space laser communication deserves to be researched. We can acquire higher transmission speed and better transmission quality between satellite and satellite, satellite and earth by setting up laser link. But in the space laser communication system,the reliability is under influences of many factors of atmosphere,detector noise, optical platform jitter and other factors. The intensity of the signal which is attenuated because of the long transmission distance is demanded to have higher intensity to acquire low BER. The channel code technology can enhance the anti-interference ability of the system. The theory of channel coding technology is that some redundancies is added to information codes. So it can make use of the checkout polynomial to correct errors at the sink port. It help the system to get low BER rate and coding gain. Reed-Solomon (RS) code is one of the channel code, and it is one kind of multi-ary BCH code, and it can correct both burst errors and random errors, and it is widely used in the error-control schemes. The new method of the RS encoder and interleaving based on the FPGA is proposed, aiming at satisfying the needs of the widely-used error control technology in the space laser communication field. An improved method for Finite Galois Field multiplier of encoding is proposed, and it is suitable for FPGA implementation. Comparison of the XOR gates cost between the optimization and original, the number of XOR gates is lessen more than 40% .Then give a new structure of interleaving by using the FPGA. By controlling the in-data stream and out-data stream of encoder, the asynchronous process of the whole frame is accomplished, while by using multi-level pipeline, the real-time transfer of the data is achieved. By controlling the read-address and write-address of the block RAM, the interleaving operation of the arbitrary depth is synchronously implemented. Compared with the normal

  19. Model-based system-of-systems engineering for space-based command, control, communication, and information architecture design

    NASA Astrophysics Data System (ADS)

    Sindiy, Oleg V.

    This dissertation presents a model-based system-of-systems engineering (SoSE) approach as a design philosophy for architecting in system-of-systems (SoS) problems. SoS refers to a special class of systems in which numerous systems with operational and managerial independence interact to generate new capabilities that satisfy societal needs. Design decisions are more complicated in a SoS setting. A revised Process Model for SoSE is presented to support three phases in SoS architecting: defining the scope of the design problem, abstracting key descriptors and their interrelations in a conceptual model, and implementing computer-based simulations for architectural analyses. The Process Model enables improved decision support considering multiple SoS features and develops computational models capable of highlighting configurations of organizational, policy, financial, operational, and/or technical features. Further, processes for verification and validation of SoS models and simulations are also important due to potential impact on critical decision-making and, thus, are addressed. Two research questions frame the research efforts described in this dissertation. The first concerns how the four key sources of SoS complexity---heterogeneity of systems, connectivity structure, multi-layer interactions, and the evolutionary nature---influence the formulation of SoS models and simulations, trade space, and solution performance and structure evaluation metrics. The second question pertains to the implementation of SoSE architecting processes to inform decision-making for a subset of SoS problems concerning the design of information exchange services in space-based operations domain. These questions motivate and guide the dissertation's contributions. A formal methodology for drawing relationships within a multi-dimensional trade space, forming simulation case studies from applications of candidate architecture solutions to a campaign of notional mission use cases, and

  20. Three Corner Sat Communications System

    NASA Technical Reports Server (NTRS)

    Anderson, Bobby; Horan, Stephen

    2000-01-01

    Three Corner Satellite is a constellation of three nanosatellites designed and built by students. New Mexico State University has taken on the design of the communications system for this constellation. The system includes the forward link, return link, and the crosslink. Due to size, mass, power, and financial constraints, we must design a small, light, power efficient, and inexpensive communications system. This thesis presents the design of a radio system to accomplish the data transmission requirements in light of the system constraints. In addition to the hardware design, the operational commands needed by the satellite's on-board computer to control and communicate with the communications hardware will be presented. In order for the hardware to communicate with the ground stations, we will examine the link budgets derived from the radiated power of the transmitters, link distance, data modulation, and data rate for each link. The antenna design for the constellation is analyzed using software and testing the physical antennas on a model satellite. After the analysis and testing, a combination of different systems will meet and exceed the requirements and constraints of the Three Corner Satellite constellation.

  1. Secure video communications systems

    SciTech Connect

    Smith, R.L.

    1991-10-08

    This patent describes a secure video communications system having at least one command network formed by a combination of subsystems. The combination of subsystems to include a video subsystem, an audio subsystem, a communications subsystem, and a control subsystem. The video communications system to be window driven and mouse operated, and having the ability to allow for secure point-to-point real-time teleconferencing.

  2. Communications systems checkout study

    NASA Technical Reports Server (NTRS)

    Ginter, W. G.

    1972-01-01

    The results and conclusions of an engineering study of Space Station communications subsystem checkout are reported. The primary purpose of the study is to recommend specific guidelines and constraints for the design and utilization of the communications subsystem leading to a practical and effective means of onboard checkout implementation. Major study objectives are as follows: (1) identify candidate communications subsystem checkout concepts, (2) determine implementation impacts of feasible concepts, (3) evaluate practicality and effectiveness of alternative concepts, (4) propose baseline modifications to accommodate preferred concepts, and (5) recommend areas for additional investigation. In addition, study results are interpreted, where appropriate, in terms of their applicability to checkout of Shuttle-Orbiter communications subsystem.

  3. C-Band Airport Surface Communications System Standards Development. Phase II Final Report. Volume 1: Concepts of Use, Initial System Requirements, Architecture, and AeroMACS Design Considerations

    NASA Technical Reports Server (NTRS)

    Hall, Edward; Isaacs, James; Henriksen, Steve; Zelkin, Natalie

    2011-01-01

    This report is provided as part of ITT s NASA Glenn Research Center Aerospace Communication Systems Technical Support (ACSTS) contract NNC05CA85C, Task 7: New ATM Requirements-Future Communications, C-Band and L-Band Communications Standard Development and was based on direction provided by FAA project-level agreements for New ATM Requirements-Future Communications. Task 7 included two subtasks. Subtask 7-1 addressed C-band (5091- to 5150-MHz) airport surface data communications standards development, systems engineering, test bed and prototype development, and tests and demonstrations to establish operational capability for the Aeronautical Mobile Airport Communications System (AeroMACS). Subtask 7-2 focused on systems engineering and development support of the L-band digital aeronautical communications system (L-DACS). Subtask 7-1 consisted of two phases. Phase I included development of AeroMACS concepts of use, requirements, architecture, and initial high-level safety risk assessment. Phase II builds on Phase I results and is presented in two volumes. Volume I (this document) is devoted to concepts of use, system requirements, and architecture, including AeroMACS design considerations. Volume II describes an AeroMACS prototype evaluation and presents final AeroMACS recommendations. This report also describes airport categorization and channelization methodologies. The purposes of the airport categorization task were (1) to facilitate initial AeroMACS architecture designs and enable budgetary projections by creating a set of airport categories based on common airport characteristics and design objectives, and (2) to offer high-level guidance to potential AeroMACS technology and policy development sponsors and service providers. A channelization plan methodology was developed because a common global methodology is needed to assure seamless interoperability among diverse AeroMACS services potentially supplied by multiple service providers.

  4. Advanced communications satellite systems

    NASA Technical Reports Server (NTRS)

    Sivo, J. N.

    1983-01-01

    There is a rapidly growing demand for satellite circuits, particularly for domestic service within the U.S. NASA's current program is aimed at developing the high risk, advanced satellite communications technologies required to significantly increase the capacity of future satellite communications systems. Attention is given to aspects of traffic distribution and service scenario, problems related to effects of rain attenuation, details regarding system configuration, a 30/20 GHz technology development approach, an experimental flight system, the communications payload for the experimental flight system, a typical experiment flight system coverage, and a typical three axis stabilized flight spacecraft.

  5. Ultramicrowave communications system, phase 2

    NASA Technical Reports Server (NTRS)

    1980-01-01

    Communications system design was completed and reviewed. Minor changes were made in order to make it more cost effective and to increase design flexibility. System design activities identified the techniques and procedures to generate and monitor high data rate test signals. Differential bi-phase demodulation is the proposed method for this system. The mockup and packaging designs were performed, and component layout and interconnection constraints were determined, as well as design drawings for dummy parts of the system. The possibility of adding a low cost option to the transceiver system was studied. The communications program has the advantage that new technology signal processing devices can be readily interfaced with the existing radio frequency subsystem to produce a short range radar.

  6. Communication system modeling

    NASA Technical Reports Server (NTRS)

    Holland, L. D.; Walsh, J. R., Jr.; Wetherington, R. D.

    1971-01-01

    This report presents the results of work on communications systems modeling and covers three different areas of modeling. The first of these deals with the modeling of signals in communication systems in the frequency domain and the calculation of spectra for various modulations. These techniques are applied in determining the frequency spectra produced by a unified carrier system, the down-link portion of the Command and Communications System (CCS). The second modeling area covers the modeling of portions of a communication system on a block basis. A detailed analysis and modeling effort based on control theory is presented along with its application to modeling of the automatic frequency control system of an FM transmitter. A third topic discussed is a method for approximate modeling of stiff systems using state variable techniques.

  7. Satellite communications system 'Tyulpan'

    NASA Astrophysics Data System (ADS)

    Tchuyan, R. K.; Tarasov, E. V.; Belousov, A. P.; Balyk, V. M.; Kovtunenko, V. M.; Morozov, V. A.; Andreev, V. A.; v'yunenko, K. A.

    1993-10-01

    A concept of the satellite communication system called 'Tyulpan' (because or its tulip-resembling shape) is considered. This conception envisages the use of six satellites-retranslators installed on high-latitude elliptic orbits. Such a system can provide the communication for mean- and high-latitude region of Europe, Asia, and America. For the communication, super small ground stations of 0.4 m in diameter can be used. In the development of system conception, the already existing technical solutions and possibility of conversion or existing installations of military destination were taken into account. Therefore, the system considered can be realized at the earliest possible date.

  8. Designing Effective Persuasive Systems Utilizing the Power of Entanglement: Communication Channel, Strategy & Affect

    ERIC Educational Resources Information Center

    Li, Haiqing

    2010-01-01

    With rapid advancements in information and communication technologies, computer-mediated communication channels such as email, web, mobile smart-phones with SMS, social networking websites (Facebook), multimedia websites, and OEM devices provide users with multiple technology choices to seek information. However, no study has compared the…

  9. China's future domestic satellite communications systems

    NASA Astrophysics Data System (ADS)

    Liang, G.; Yaokun, Y.

    1985-01-01

    Some ideas about China's future domestic satellite communications system are discussed. The following objectives are considered in the design of the new domestic satellite communications system: (1) the satellite communications system should link the entire country and form a unified national network with the existing ground communications system, (2) based on the geographic situation, the satellite communications system should be primarily small and scattered in the west, and large and concentrated in the east, (3) the Telephone business should be the primary business of the satellite communications system. It should also be capable of transmitting television, telegram, data, facsimile, and broadcasting, (4) the communications system should be primarily designed as a single jump system. It should not exceed two jumps, and (5) the parameters of the communications system should be in agreement with CCIR and CCITT recommendations.

  10. Integrated Communication Systems.

    ERIC Educational Resources Information Center

    Simpson, Ward

    2003-01-01

    Describes the Internet-based information system that has provided effective communications and reporting for the upgrade to K-12 schools in Scottsdale, Arizona. The Website and software applications created valuable communications in the construction process and improved reporting on progress. (SLD)

  11. 33 CFR 127.1111 - Communication systems.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... Waterfront Facilities Handling Liquefied Hazardous Gas Design and Construction § 127.1111 Communication systems. (a) The marine transfer area for LHG must possess a communication system that enables continuous... 33 Navigation and Navigable Waters 2 2010-07-01 2010-07-01 false Communication systems....

  12. Network design consideration of a satellite-based mobile communications system

    NASA Technical Reports Server (NTRS)

    Yan, T.-Y.

    1986-01-01

    Technical considerations for the Mobile Satellite Experiment (MSAT-X), the ground segment testbed for the low-cost spectral efficient satellite-based mobile communications technologies being developed for the 1990's, are discussed. The Network Management Center contains a flexible resource sharing algorithm, the Demand Assigned Multiple Access scheme, which partitions the satellite transponder bandwidth among voice, data, and request channels. Satellite use of multiple UHF beams permits frequency reuse. The backhaul communications and the Telemetry, Tracking and Control traffic are provided through a single full-coverage SHF beam. Mobile Terminals communicate with the satellite using UHF. All communications including SHF-SHF between Base Stations and/or Gateways, are routed through the satellite. Because MSAT-X is an experimental network, higher level network protocols (which are service-specific) will be developed only to test the operation of the lowest three levels, the physical, data link, and network layers.

  13. Database approach to communication in VLSI design

    NASA Astrophysics Data System (ADS)

    Wiederhold, G.; Beetem, A.; Short, G.

    1980-10-01

    This paper describes recent and planned work at Stanford in applying database technology to the problems of VLSI design. In particular, it addresses the issue of communication within a design's different representations and hierarchical levels in a multiple designer environment. We demonstrate the heretofore questioned utility of using commercial database systems, at least while developing a versatile, flexible, and generally efficient model and its associated communication paths. Completed work and results from initial work using DEC DBMS 20 is presented, including macro expansion within the database, and signalling of changes to higher structural levels. Considerable discussion regarding overall philosophy for continued work is also included.

  14. Designing A Robust Command, Communications and Data Acquisition System For Autonomous Sensor Platforms Using The Data Transport Network

    NASA Astrophysics Data System (ADS)

    Valentic, T. A.

    2012-12-01

    The Data Transport Network is designed for the delivery of data from scientific instruments located at remote field sites with limited or unreliable communications. Originally deployed at the Sondrestrom Research Facility in Greenland over a decade ago, the system supports the real-time collection and processing of data from large instruments such as incoherent scatter radars and lidars. In recent years, the Data Transport Network has been adapted to small, low-power embedded systems controlling remote instrumentation platforms deployed throughout the Arctic. These projects include multiple buoys from the O-Buoy, IceLander and IceGoat programs, renewable energy monitoring at the Imnavait Creek and Ivotuk field sites in Alaska and remote weather observation stations in Alaska and Greenland. This presentation will discuss the common communications controller developed for these projects. Although varied in their application, each of these systems share a number of common features. Multiple instruments are attached, each of which needs to be power controlled, data sampled and files transmitted offsite. In addition, the power usage of the overall system must be minimized to handle the limited energy available from sources such as solar, wind and fuel cells. The communications links are satellite based. The buoys and weather stations utilize Iridium, necessitating the need to handle the common drop outs and high-latency, low-bandwidth nature of the link. The communications controller is an off-the-shelf, low-power, single board computer running a customized version of the Linux operating system. The Data Transport Network provides a Python-based software framework for writing individual data collection programs and supplies a number of common services for configuration, scheduling, logging, data transmission and resource management. Adding a new instrument involves writing only the necessary code for interfacing to the hardware. Individual programs communicate with the

  15. Feasibility Study on a Portable Field Pest Classification System Design Based on DSP and 3G Wireless Communication Technology

    PubMed Central

    Han, Ruizhen; He, Yong; Liu, Fei

    2012-01-01

    This paper presents a feasibility study on a real-time in field pest classification system design based on Blackfin DSP and 3G wireless communication technology. This prototype system is composed of remote on-line classification platform (ROCP), which uses a digital signal processor (DSP) as a core CPU, and a host control platform (HCP). The ROCP is in charge of acquiring the pest image, extracting image features and detecting the class of pest using an Artificial Neural Network (ANN) classifier. It sends the image data, which is encoded using JPEG 2000 in DSP, to the HCP through the 3G network at the same time for further identification. The image transmission and communication are accomplished using 3G technology. Our system transmits the data via a commercial base station. The system can work properly based on the effective coverage of base stations, no matter the distance from the ROCP to the HCP. In the HCP, the image data is decoded and the pest image displayed in real-time for further identification. Authentication and performance tests of the prototype system were conducted. The authentication test showed that the image data were transmitted correctly. Based on the performance test results on six classes of pests, the average accuracy is 82%. Considering the different live pests’ pose and different field lighting conditions, the result is satisfactory. The proposed technique is well suited for implementation in field pest classification on-line for precision agriculture. PMID:22736996

  16. Feasibility study on a portable field pest classification system design based on DSP and 3G wireless communication technology.

    PubMed

    Han, Ruizhen; He, Yong; Liu, Fei

    2012-01-01

    This paper presents a feasibility study on a real-time in field pest classification system design based on Blackfin DSP and 3G wireless communication technology. This prototype system is composed of remote on-line classification platform (ROCP), which uses a digital signal processor (DSP) as a core CPU, and a host control platform (HCP). The ROCP is in charge of acquiring the pest image, extracting image features and detecting the class of pest using an Artificial Neural Network (ANN) classifier. It sends the image data, which is encoded using JPEG 2000 in DSP, to the HCP through the 3G network at the same time for further identification. The image transmission and communication are accomplished using 3G technology. Our system transmits the data via a commercial base station. The system can work properly based on the effective coverage of base stations, no matter the distance from the ROCP to the HCP. In the HCP, the image data is decoded and the pest image displayed in real-time for further identification. Authentication and performance tests of the prototype system were conducted. The authentication test showed that the image data were transmitted correctly. Based on the performance test results on six classes of pests, the average accuracy is 82%. Considering the different live pests' pose and different field lighting conditions, the result is satisfactory. The proposed technique is well suited for implementation in field pest classification on-line for precision agriculture. PMID:22736996

  17. 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.

  18. Communication and Information Needs for Effective Administration of the Bolivian System of Public Instruction: A Report and Design.

    ERIC Educational Resources Information Center

    Garret, Max Mehlis; Rorex, A. Rexford

    The administrative information and communication system for public education in Bolivia has been a matter of concern to the authors for several years. This report is the outgrowth of that concern. Part 1 describes the present communications/information system and concludes that there is a weak infrastructure together with a total lack of…

  19. Group Communication through Computers. Volume 1: Design and Use of the FORUM System. IFF Report R-32.

    ERIC Educational Resources Information Center

    Vallee, Jacques; And Others

    To explore the feasibility and usefulness of group communication via computer, a system called FORUM was constructed and used in research and management tasks using ARPANET, an international computer network. Working softward and data regarding the dynamics of groups using network communication were developed, and a prototype hardware system for…

  20. Serial interprocessor communications system

    SciTech Connect

    Labiak, W.; Siemens, P.; Bailey, C.

    1980-04-03

    A serial communications system based on the EIA RS232-C standard with modem control lines has been developed. The DLV11-E interface is used for this purpose. All handshaking is done with the modem control lines. This allows totally independent full duplex communication. The message format consists of eight bit data with odd parity and a sixteen bit checksum on the whole message. All communications are fully interrupt driven. A program was written to load a program into a remote LSI-11 using the serial line without bootstrap ROM.

  1. Digital communication system

    NASA Technical Reports Server (NTRS)

    Monford, L. G., Jr. (Inventor)

    1974-01-01

    A digital communication system is reported for parallel operation of 16 or more transceiver units with the use of only four interconnecting wires. A remote synchronization circuit produces unit address control words sequentially in data frames of 16 words. Means are provided in each transceiver unit to decode calling signals and to transmit calling and data signals. The transceivers communicate with each other over one data line. The synchronization unit communicates the address control information to the transceiver units over an address line and further provides the timing information over a clock line. A reference voltage level or ground line completes the interconnecting four wire hookup.

  2. Rectangular Microstirp Patch Antenna Design at THz Frequency for Short Distance Wireless Communication Systems

    NASA Astrophysics Data System (ADS)

    Sharma, Aditi; Singh, G.

    2009-01-01

    In this paper, we have presented the simulation results of a rectangular microstrip patch antenna at terahertz (THz) frequency ranging from 0.7 to 0.85 THz. THz electromagnetic wave can permit more densely packed communication links with increased security of communication transmission. The simulated results such as gain, radiation efficiency and 10 dB impedance bandwidth of rectangular microstrip patch antenna at THz frequencies without shorting post configuration are 3.497 dB, 55.71% and 17.76%, respectively, whereas with shorting post configuration, corresponding parameters are 3.502 dB, 55.88% and 17.27%. The simulation has been performed by using CST Microwave Studio, which is a commercially available electromagnetic simulator based on the method of finite difference time domain technique.

  3. Design And Analysis Of Optical Communication Links

    NASA Technical Reports Server (NTRS)

    Lesh, J. R.; Marshall, W. K.; Katz, J.

    1989-01-01

    To convey to prospective designers intuitive understanding based on unique characteristics of optical communication systems, report presents method of design and analysis of outer-space optical communication link using pulse-position modulation (PPM) and in which received signal sufficiently weak to require detection by photomultiplier operating in photon-counting mode. Step 1 requires some knowledge or assumptions about parameters of transmitter and receiver. Step 2 determination of average number of background-noise photons detected during PPM timeslot. Step 3 average number, Ps of signal photons detected per signal pulse compared with average number, Pn of noise pulses detected per PPM timeslot.

  4. The ORBCOMM data communications system

    NASA Technical Reports Server (NTRS)

    Schoen, David C.; Locke, Paul A.

    1993-01-01

    The ORBCOMM system is designed to provide low-cost, two-way data communications for mobile and remote users. The communications system is ideally configured for low data rate applications where communicating devices are geographically dispersed and two-way communications through terrestrial means is cumbersome and not cost effective. The remote terminals use VHF frequencies which allow for the use of very small, low-cost terminals. ORBCOMM has entered into joint development agreements with several large manufacturers of both consumer and industrial electronics to design and build the remote terminals. Based on prototype work, the estimated retail cost of these units will range from $50 to $400 depending on the complexity of the design. Starting in the fall of 1993, ORBCOMM will begin service with a demonstration network consisting of two operating satellites. By the end of 1994, a full operating network of 26 satellites, four Gateway Earth Stations, and a Network Control Center will be in place. The full constellation will provide full coverage of the entire world with greater than 94 percent communications availability for the continental U.S. This paper describes the ORBCOMM system, the technology used in its implementation, and its applications.

  5. The Skylab communications system.

    NASA Technical Reports Server (NTRS)

    Disher, J. H.

    1972-01-01

    Skylab is an experimental manned space station which will be operated by three astronauts intermittently over eight months in 1973. It will be in a 235 nautical mile, 50 degree inclination orbit. The communication system includes an onboard audio distribution hard-line network with 13 stations; a teleprinter for recording messages from the ground; telemetry, voice and television links; an onboard video distribution network. The radio frequencies system also includes radiometer and scatterometer earth-scanning sensors operating at 13.9 GHz and 1.4 GHz. The overall Skylab Program is discussed briefly and the communications system is described in more detail.

  6. Airborne space laser communication system and experiments

    NASA Astrophysics Data System (ADS)

    Li, Xiao-Ming; Zhang, Li-zhong; Meng, Li-Xin

    2015-11-01

    Airborne space laser communication is characterized by its high speed, anti-electromagnetic interference, security, easy to assign. It has broad application in the areas of integrated space-ground communication networking, military communication, anti-electromagnetic communication. This paper introduce the component and APT system of the airborne laser communication system design by Changchun university of science and technology base on characteristic of airborne laser communication and Y12 plan, especially introduce the high communication speed and long distance communication experiment of the system that among two Y12 plans. In the experiment got the aim that the max communication distance 144Km, error 10-6 2.5Gbps - 10-7 1.5Gbps capture probability 97%, average capture time 20s. The experiment proving the adaptability of the APT and the high speed long distance communication.

  7. Satellite personal communications system

    NASA Technical Reports Server (NTRS)

    Reilly, N. B.; Smith, J. G. (Inventor)

    1980-01-01

    Voice channel communication between low power mobile stations dispersed over a large area is provided by a system which includes a geostationary satellite utilizing a large UHF antenna that can receive a transmission from a caller and retransmit it over any one beam of a matrix of narrow beams, so the chosen beam covers an area in which a designated called party is located. A single up-link control channel occupying a narrow frequency band, can be utilized to receive dial up signals from a caller, and another single down link control channel can be utilized to ring up the called party located anywhere within the continental United States. The satellite antenna includes a matrix of feed horns that not only direct the beams in a controlled matrix onto the area of the continental United States, but also permit detection of the region from which the caller's signal is transmitted and the region from which the called party's answer is received, to enable the interconnection of signals received from these two regions. The system is particularly useful for rural areas.

  8. INMARSAT's personal communicator system

    NASA Technical Reports Server (NTRS)

    Hart, Nick; Haugli, HANS-C.; Poskett, Peter; Smith, K.

    1993-01-01

    Inmarsat has been providing near global mobile satellite communications since 1982 and Inmarsat terminals are currently being used in more than 130 countries. The terminals have been reduced in size and cost over the years and new technology has enabled the recent introduction of briefcase sized personal telephony terminals (Inmarsat-M). This trend continues and we are likely to see Inmarsat handheld terminals by the end of the decade. These terminals are called Inmarsat-P and this paper focuses on the various elements required to support a high quality service to handheld terminals. The main system elements are: the handheld terminals; the space segment with the associated orbits; and the gateways to terrestrial networks. It is both likely and desirable that personal handheld satellite communications will be offered by more than one system provider and this competition will ensure strong emphasis on service quality and cost of ownership. The handheld terminals also have to be attractive to a large number of potential users, and this means that the terminals must be small enough to fit in a pocket. Battery lifetime is another important consideration, and this coupled with radiation safety requirements limits the maximum radiated EIRP. The terminal G/T is mainly constrained by the gain of the omnidirectional antenna and the noise figure of the RF front end (including input losses). Inmarsat has examined, with the support of industry, a number of Geosynchronous (GSO), Medium Earth Orbit (MEO) and Low Earth Orbit (LEO) satellite options for the provision of a handheld mobile satellite service. This paper describes the key satellite and orbit parameters and tradeoffs which affect the overall quality of service and the space segment costing. The paper also stresses not only the importance of using and sharing the available mobile frequency band allocations efficiently, but also the key considerations affecting the choice of feeder link bands. The design of the gateways

  9. Airborne wireless communication systems, airborne communication methods, and communication methods

    DOEpatents

    Deaton, Juan D.; Schmitt, Michael J.; Jones, Warren F.

    2011-12-13

    An airborne wireless communication system includes circuitry configured to access information describing a configuration of a terrestrial wireless communication base station that has become disabled. The terrestrial base station is configured to implement wireless communication between wireless devices located within a geographical area and a network when the terrestrial base station is not disabled. The circuitry is further configured, based on the information, to configure the airborne station to have the configuration of the terrestrial base station. An airborne communication method includes answering a 911 call from a terrestrial cellular wireless phone using an airborne wireless communication system.

  10. How the Ethnography of Communication Provides Resources for Design

    ERIC Educational Resources Information Center

    Leighter, James L.; Rudnick, Lisa; Edmonds, Theresa J.

    2013-01-01

    Designing solutions to social problems requires some degree of interpretive accountability to the sociocultural systems in which design solutions must live. Our case studies show how ethnography of communication research generates distinctive resources for design. (Contains 5 notes.)

  11. Space Shuttle communications and tracking system

    NASA Technical Reports Server (NTRS)

    Tu, Kwei; Cravey, Donald N.; Kuo, Yeng S.; Johnson, John H.; Teasdale, William E.

    1987-01-01

    This paper is intended to provide a comprehensive description of the Space Shuttle communications and tracking system design, development, and system operations. Areas of special innovative communications techniques implemented by the Space Shuttle such as source encoding, channel encoding, spread spectrum, and digital modulation are emphasized. In addition, the role of the Electronics Systems Test Laboratory in the development of the system is discussed.

  12. Design of high-order HTS dual-band bandpass filters with receiver subsystem for future mobile communication systems

    NASA Astrophysics Data System (ADS)

    Sekiya, N.

    2016-08-01

    We have developed two high-order high-temperature superconducting (HTS) dual-band bandpass filters (BPFs) with a receiver subsystem for future mobile communication systems. They feature stub-loaded hair-pin resonators with two types of microstrip lines between them. One has a six-pole design, and the other has an eight-pole design. Both were designed to operate at 2.15 GHz with a 43-MHz (2%) bandwidth for the lower passband and at 3.50 GHz with a 70-MHz (2%) bandwidth for the upper one. They were fabricated using YBa2Cu3Oy thin film on a CeO2-bufferd r-Al2O3 substrate. The measured results for both filters agree well with the simulated ones. The HTS dual-band BPF receiver subsystem uses a pulse tube cryocooler and a wideband low noise amplifier (LNA). We measured the frequency response of the six-pole dual-band BPF with and without a wideband LNA with a gain of 10 dB. The measured return losses were close.

  13. Communication Systems. Laboratory Activities.

    ERIC Educational Resources Information Center

    Sutherland, Barbara, Ed.

    This communication systems guide provides teachers with learning activities for secondary students. Introductory materials include an instructional planning outline and worksheet, an outline of essential elements, a list of objectives, a course description, and a content outline. The guide contains 32 modules on the following topics: story…

  14. Design and implementation of picture archiving and communication system in Huadong Hospital

    NASA Astrophysics Data System (ADS)

    Zhang, Jianguo; Zhou, Zheng; Zhuang, Jun; Han, Ruolin; Zhang, Guozhen; Feng, Jie; Wang, Mingpeng; Wang, Chuanfu

    2001-08-01

    Huadong hospital in Shanghai with 700 beds provides health care services for inpatients and outpatients, as well as special senior and VIP patients. In order to move to digital imaging based radiology practice, and also provide better intra-hospital clinical services for senior and VIP patients, we started designing and planning PACS implementation from September of 1999. Based on the radiology service model and current workflow in Huadong hospital, we implemented PACS in three steps.

  15. Designing a Model for Integration of Information and Communication Technologies (ICTs) in the Iranian Agricultural Research System

    ERIC Educational Resources Information Center

    Sharifzadeh, Aboulqasem; Abdollahzadeh, Gholam Hossein; Sharifi, Mahnoosh

    2009-01-01

    Capacity Development is needed in the Iranian Agricultural System. Integrating Information and Communication Technologies (ICTs) in the agricultural research system is an appropriate capacity development mechanism. The appropriate application of ICTs and information such as a National Agricultural Information System requires a systemically…

  16. Simulating Rain Fade In A Communication System

    NASA Technical Reports Server (NTRS)

    Shalkhauser, Kurt A.; Nagy, Lawrence A.; Svoboda, James K.

    1994-01-01

    Automated, computer-controlled assembly of electronic equipment developed for use in simulation testing of downlink portion of Earth/satellite microwave digital communication system. Designed to show effects upon performance of system of rain-induced fading in received signal and increases in transmitted power meant to compensate for rain-induced fading. Design of communication system improved iteratively in response to results of simulations, leading eventually to design ensuring clear, uninterrupted transmission of digital signals.

  17. VLSI Design of a Variable-Length FFT/IFFT Processor for OFDM-Based Communication Systems

    NASA Astrophysics Data System (ADS)

    Kuo, Jen-Chih; Wen, Ching-Hua; Lin, Chih-Hsiu; Wu, An-Yeu (Andy)

    2003-12-01

    The technique of orthogonal frequency division multiplexing (OFDM) is famous for its robustness against frequency-selective fading channel. This technique has been widely used in many wired and wireless communication systems. In general, the fast Fourier transform (FFT) and inverse FFT (IFFT) operations are used as the modulation/demodulation kernel in the OFDM systems, and the sizes of FFT/IFFT operations are varied in different applications of OFDM systems. In this paper, we design and implement a variable-length prototype FFT/IFFT processor to cover different specifications of OFDM applications. The cached-memory FFT architecture is our suggested VLSI system architecture to design the prototype FFT/IFFT processor for the consideration of low-power consumption. We also implement the twiddle factor butterfly processing element (PE) based on the coordinate rotation digital computer (CORDIC) algorithm, which avoids the use of conventional multiplication-and-accumulation unit, but evaluates the trigonometric functions using only add-and-shift operations. Finally, we implement a variable-length prototype FFT/IFFT processor with TSMC[InlineEquation not available: see fulltext.]m 1P4M CMOS technology. The simulations results show that the chip can perform ([InlineEquation not available: see fulltext.]-[InlineEquation not available: see fulltext.])-point FFT/IFFT operations up to[InlineEquation not available: see fulltext.] operating frequency which can meet the speed requirement of most OFDM standards such as WLAN, ADSL, VDSL ([InlineEquation not available: see fulltext.]), DAB, and[InlineEquation not available: see fulltext.]-mode DVB.

  18. 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.

  19. Using apprenticeship communication flow as an ergonomic design input for future OR systems.

    PubMed

    Ten Kate; Lange; Kleinrensink; van Veelen; Goossens

    2004-06-01

    Removing the gallbladder is a relatively simple laparoscopic operation. Tissue trauma, caused by laparoscopic cholecystectomy, is usually minimal. Misidentifying the cystic duct and artery and the common hepatic duct represents the most severe complication. However, the Critical View of Safety (CVS) technique reduces the risk of trauma, by accomplishing a safe 360 degrees identification of the cystic duct origin at the gallbladder neck [5]. This technique is employed and trained at the Erasmus Medical Centre (EMC), Rotterdam, The Netherlands. This study presents the potential value of a training device which residents can use during practice. This training device must cover both user friendliness and information supply. The current information supply was studied subjectively; the CVS protocol and the users' experience were studied both objectively and subjectively. The results of these studies show that the present information supply is not satisfactory, that there is a CVS protocol which can be easily used in a training device, and that most actions defining the cystic duct during operation revert on users' experience. Therefore, it is desirable to design a new training device according to the experience of the target group and the protocols, and taking into account an optimal human-product interaction. PMID:16754501

  20. Wireless Headset Communication System

    NASA Technical Reports Server (NTRS)

    Lau, Wilfred K.; Swanson, Richard; Christensen, Kurt K.

    1995-01-01

    System combines features of pagers, walkie-talkies, and cordless telephones. Wireless headset communication system uses digital modulation on spread spectrum to avoid interference among units. Consists of base station, 4 radio/antenna modules, and as many as 16 remote units with headsets. Base station serves as network controller, audio-mixing network, and interface to such outside services as computers, telephone networks, and other base stations. Developed for use at Kennedy Space Center, system also useful in industrial maintenance, emergency operations, construction, and airport operations. Also, digital capabilities exploited; by adding bar-code readers for use in taking inventories.

  1. Robust reliable control design for networked control system with sampling communication

    NASA Astrophysics Data System (ADS)

    Sakthivel, R.; Santra, Srimanta; Mathiyalagan, K.; Su, Hongye

    2015-12-01

    In this article, the problem of robust exponential stability and reliable stabilisation for a class of continuous-time networked control systems (NCSs) with a sample-data controller and unknown time-varying sampling rate is considered. The analysis is based on average dwell-time, Lyapunov-Krasovskii functional and linear matrix inequality (LMI) technique. The delay-dependent criteria are developed for ensuring the robust exponential stability of the considered NCSs. The obtained conditions are formulated in terms of LMIs that can easily be solved by using standard software packages. Furthermore, the result is extended to study the robust stabilisation for NCS with parameter uncertainties. A state feedback controller is constructed in terms of the solution to a set of LMIs, which guarantee the robust exponential stabilisation of NCS and the controller. Finally, numerical examples are presented to illustrate the effectiveness of the obtained results.

  2. Odyssey personal communications satellite system

    NASA Technical Reports Server (NTRS)

    Spitzer, Christopher J.

    1993-01-01

    The spectacular growth of cellular telephone networks has proved the demand for personal communications. Large regions of the world are too sparsely populated to be economically served by terrestrial cellular communications. Since satellites are well suited to this application, TRW filed with the FCC on May 31, 1993 for the Odyssey construction permit. Odyssey will provide high quality wireless communication services worldwide from satellites. These services will include: voice, data, paging, and messaging. Odyssey will be an economical approach to providing communications. A constellation of 12 satellites will be orbited in three, 55 deg. inclined planes at an altitude of 10,354 km to provide continuous coverage of designated regions. Two satellites will be visible anywhere in the world at all times. This dual visibility leads to high line-of-sight elevation angles, minimizing obstructions by terrain, trees and buildings. Each satellite generates a multibeam antenna pattern that divides its coverage area into a set of contiguous cells. The communications system employs spread spectrum CDMA on both the uplinks and downlinks. This signaling method permits band sharing with other systems and applications. Signal processing is accomplished on the ground at the satellite's 'Gateway' stations. The 'bent pipe' transponders accommodates different regional standards, as well as signaling changes over time. The low power Odyssey handset will be cellular compatible. Multipath fade protection is provided in the handset.

  3. On the design of few-mode Er-doped fiber amplifiers for space-division multiplexing optical communications systems

    NASA Astrophysics Data System (ADS)

    Herbster, A.; Romero, M. A.

    2014-05-01

    Long-haul optical communications links based on space-division multiplexing use space as the final degree of multiplexing freedom, possibly exploring the modal orthogonality in a few-mode fiber (FMF). However, if conventional EDFAs are used, each mode will experience a different value of optical gain, on account of distinct field profile configurations. This lack of gain equalization imposes difficulties for mode demultiplexing and may impair the system performance. The FMF-EDFA designer should define Er doping and/or refractive index profiles, as well as the pumping configuration, to provide the best possible mode equalization of optical gain and noise figure. In the case of the FMFEDFA, the problem is involved because each mode contributes with its own set of coupled differential equations. To use this approach to carry out a rigorous optimization procedure is not feasible and typical FMF-EDFAs designs proposed in the literature are empirical. A novel optimization method is proposed here. The definition of a figure of merit related to the equalization of the pump-mode signal overlap integral significantly reduces computation time, allowing the implementation of a multiobjective optimization approach. The results obtained were validated against the solution provided by the full set of rate and propagation equations and we conducted a FMF-EDFA optimization case study. Our double-ring Er doping profile design requires a single 350 mW LP11,p pump to provide a mean gain of 21.6 dB, within 0.6 dB of equalization for each of the four modes considered.

  4. 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.

  5. Orbital Maneuvering Vehicle space station communications design

    NASA Technical Reports Server (NTRS)

    Arndt, D.; Novosad, S. W.; Tu, K.; Loh, Y. C.; Kuo, Y. S.

    1988-01-01

    The authors present an Orbital Maneuvering Vehicle space station communications systems design approach which is intended to satisfy the stringent link requirements. The operational scenario, system configuration, signal design, antenna system management, and link performance analysis are discussed in detail. It is shown that the return link can transmit up to 21.6 Mb/s and maintain at least a 3-dB link margin through proper power and antenna management control at a maximum distance of 37 km. It is suggested that the proposed system, which is compatible with the space station multiple-access system, can be a model for other space station interoperating elements or users to save the development cost and reduce the technical and schedule risks.

  6. 49 CFR 193.2519 - Communication systems.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... primary communication system that provides for verbal communications between all operating personnel at...) storage capacity must have an emergency communication system that provides for verbal communications... operation of safety equipment in time of emergency. The emergency communication system must be...

  7. Design and implementation of an Internet based effective controlling and monitoring system with wireless fieldbus communications technologies for process automation--an experimental study.

    PubMed

    Cetinceviz, Yucel; Bayindir, Ramazan

    2012-05-01

    The network requirements of control systems in industrial applications increase day by day. The Internet based control system and various fieldbus systems have been designed in order to meet these requirements. This paper describes an Internet based control system with wireless fieldbus communication designed for distributed processes. The system was implemented as an experimental setup in a laboratory. In industrial facilities, the process control layer and the distance connection of the distributed control devices in the lowest levels of the industrial production environment are provided with fieldbus networks. In this paper, the Internet based control system that will be able to meet the system requirements with a new-generation communication structure, which is called wired/wireless hybrid system, has been designed on field level and carried out to cover all sectors of distributed automation, from process control, to distributed input/output (I/O). The system has been accomplished by hardware structure with a programmable logic controller (PLC), a communication processor (CP) module, two industrial wireless modules and a distributed I/O module, Motor Protection Package (MPP) and software structure with WinCC flexible program used for the screen of Scada (Supervisory Control And Data Acquisition), SIMATIC MANAGER package program ("STEP7") used for the hardware and network configuration and also for downloading control program to PLC. PMID:22306882

  8. EDUCATIONAL COMMUNICATIONS SYSTEM--PHASE III.

    ERIC Educational Resources Information Center

    WITHERSPOON, JOHN P.; AND OTHERS

    MULTIPURPOSE COMMUNICATIONS SYSTEM MODELS WERE DEVELOPED FOR APPLICATION TO HIGHER EDUCATION. THREE MODEL SYSTEMS - INTRASTATE, INTERSTATE, AND EDUCATIONAL RESOURCES - WERE DESIGNED. THESE SYSTEM DESIGNS WERE ESTABLISHED FOR EASY EVALUATION AND MAXIMUM FLEXIBILITY, WITH A MINIMUM OF PRESET AUTOMATIC EQUIPMENT. TWO ALTERNATIVE TRANSMISSION SYSTEMS…

  9. Communication vs Realism for the Learning Designer.

    ERIC Educational Resources Information Center

    Caldwell, George

    In theatrical production, skillful design is effective communication. A study of audience response to nine drama settings gives positive evidence that the successful designer creates "signposts and symbols" that communicate instantaneously to the observer. The setting is a message. All of the scenic elements must be unified in a clear and concise…

  10. Preliminary Thoughts on Netted Cable Communication Systems.

    ERIC Educational Resources Information Center

    Eldridge, Frank; Mason, William

    There are five categories of cable communication systems: Conventional Community Antenna Television (CATV), Pay-TV, Subscriber Response Systems, Electronic Information Handling Systems, and Two-Way Audio/Visual Systems. CATV and Pay-TV systems are designed for the one-way transmission of programs, the former providing for better quality…

  11. EHF SATCOM system design

    NASA Astrophysics Data System (ADS)

    Ahmed, M. Jamil

    Future satellite systems will differ considerably from the current versions. The impetus for change is a result of the need for more capacity, wider bandwidth requirements for enhanced services, increasing demand for mobile communications, advances in technology, developments in satellite payload systems, and a demand for secure military communications. To a large extent all of these needs can be satisfied by the use of extremely high frequency satellite communication (EHF Satcom) systems. EHF Satcom system design, features, pros and cons of using the system, particularly for military applications, and the current status of EHF SATCOM in Canada, U.S., Europe, and Japan are examined. The demand for bandwidth will continue to increase due to the growth of communication as well as due to enhanced services for business and entertainment. The increased bandwidth needs will be met by operating at higher frequencies, and perhaps by using extremely high frequency/superhigh frequency (EHF/SHF) satellites. Design of such systems involves a consideration of numerous aspects of design, technology, cost, and services. Advances in technology will make EHF/SHF systems feasible for military applications, as well as commercial mobile terminals, and high data rate terminals. The use of higher frequencies and small antennas will aid mobile communications. On-board processing will be akin to putting a switch in the space, providing flexibility of rates, connectivity, and services.

  12. Digital and analog communication systems

    NASA Technical Reports Server (NTRS)

    Shanmugam, K. S.

    1979-01-01

    The book presents an introductory treatment of digital and analog communication systems with emphasis on digital systems. Attention is given to the following topics: systems and signal analysis, random signal theory, information and channel capacity, baseband data transmission, analog signal transmission, noise in analog communication systems, digital carrier modulation schemes, error control coding, and the digital transmission of analog signals.

  13. Principles of military communication systems

    NASA Astrophysics Data System (ADS)

    Torrieri, D. J.

    This book is devoted to an analytical study of those aspects of communication theory which have special relevance to military systems. The book is intended for graduate students and practicing engineers with a background in communication theory. Aspects of communication warfare are considered, taking into account power and propagation, analog communications, digital communications, and pulsed jamming. Pseudonoise spread-spectrum systems are examined, giving attention to principles, pseudonoise sequences, the concealment of pseudonoise waveforms, error probabilities in presence of interference, jamming, code synchronization, pseudonoise networks, and burst-communication systems. Frequency hopping is discussed along with interception, adaptive antenna systems, and cryptographic digital communications. Topics reviewed in an appendix are related to derivations of conditional bit error probabilities for frequency-shift keying, and the noncentral chi-squared distribution.

  14. Survey of Interlibrary Communications Systems.

    ERIC Educational Resources Information Center

    Kenney, Brigitte L.

    The growth and development of library networks increased the need for more rapid interlibrary communication. This survey describes the history, costs and recent developments of various means of interlibrary communication. Extensive references are provided for each area. The communications systems discussed are: surveys, mail, telephone, facsimile,…

  15. Information Systems and Business Communication.

    ERIC Educational Resources Information Center

    Beswick, Raymond W., Ed.; Williams, Alfred B., Ed.

    Intended to provide orientation about the integration of business communication, business systems, and the researching and teaching of business communication, this books offers articles on a variety of topics concerning business communication. Titles of the articles and their authors are as follows: (1) "Office Technology: Voice Store-and-Forward"…

  16. Design of Test Articles and Monitoring System for the Characterization of HIRF Effects on a Fault-Tolerant Computer Communication System

    NASA Technical Reports Server (NTRS)

    Torres-Pomales, Wilfredo; Malekpour, Mahyar R.; Miner, Paul S.; Koppen, Sandra V.

    2008-01-01

    This report describes the design of the test articles and monitoring systems developed to characterize the response of a fault-tolerant computer communication system when stressed beyond the theoretical limits for guaranteed correct performance. A high-intensity radiated electromagnetic field (HIRF) environment was selected as the means of injecting faults, as such environments are known to have the potential to cause arbitrary and coincident common-mode fault manifestations that can overwhelm redundancy management mechanisms. The monitors generate stimuli for the systems-under-test (SUTs) and collect data in real-time on the internal state and the response at the external interfaces. A real-time health assessment capability was developed to support the automation of the test. A detailed description of the nature and structure of the collected data is included. The goal of the report is to provide insight into the design and operation of these systems, and to serve as a reference document for use in post-test analyses.

  17. Spacecraft design project: High latitude communications satellite

    NASA Technical Reports Server (NTRS)

    Josefson, Carl; Myers, Jack; Cloutier, Mike; Paluszek, Steve; Michael, Gerry; Hunter, Dan; Sakoda, Dan; Walters, Wes; Johnson, Dennis; Bauer, Terry

    1989-01-01

    The spacecraft design project was part of AE-4871, Advanced Spacecraft Design. The project was intended to provide experience in the design of all major components of a satellite. Each member of the class was given primary responsibility for a subsystem or design support function. Support was requested from the Naval Research Laboratory to augment the Naval Postgraduate School faculty. Analysis and design of each subsystem was done to the extent possible within the constraints of an eleven week quarter and the design facilities (hardware and software) available. The project team chose to evaluate the design of a high latitude communications satellite as representative of the design issues and tradeoffs necessary for a wide range of satellites. The High-Latitude Communications Satellite (HILACS) will provide a continuous UHF communications link between stations located north of the region covered by geosynchronous communications satellites, i.e., the area above approximately 60 N latitude. HILACS will also provide a communications link to stations below 60 N via a relay Net Control Station (NCS), which is located with access to both the HILACS and geosynchronous communications satellites. The communications payload will operate only for that portion of the orbit necessary to provide specified coverage.

  18. A Wireless Communications Systems Laboratory Course

    ERIC Educational Resources Information Center

    Guzelgoz, Sabih; Arslan, Huseyin

    2010-01-01

    A novel wireless communications systems laboratory course is introduced. The course teaches students how to design, test, and simulate wireless systems using modern instrumentation and computer-aided design (CAD) software. One of the objectives of the course is to help students understand the theoretical concepts behind wireless communication…

  19. Cryptography in a communication system

    NASA Astrophysics Data System (ADS)

    Best, M. R.

    1982-10-01

    Communication system protection by cryptography is reviewed. Privacy and authentication problems are discussed. Conventional cryptographic systems as well as public key systems are complementary. Classical security methods such as signed contracts, physical locks, passwords and keys remain important.

  20. Designing Your Intercultural Communication Course.

    ERIC Educational Resources Information Center

    Straub, Hans

    This paper presents suggestions for a 60-hour course in intercultural communication that develops cognition skills needed to understand life in foreign countries. The initial part of the course is intended to heighten the participant's awareness of his or her own "home-culture"; the latter part concentrates on assumptions, values, and behaviors of…

  1. Design concepts for hardened communications structures

    NASA Astrophysics Data System (ADS)

    Flathau, William J.; Smith, William G.

    1990-03-01

    An important component of any hardened command and control structure is the antenna system that provides communication with the outside world. Two types of antennae were considered; i.e., the whip type and the directional. The whip type is for short range communication and the directional is for use primarily with satellites. In the super high frequency range, the use of directional antennae having parabolic dishes greater than 8 feet in diameter are common. In the very extra high frequency range, dishes that are 2 to 3 feet in diameter are used. The whip type antenna should extend up to, say, 60 feet in the air. Based on this background, a family of structures was designed that can protect whip and directional antennae from the blast and shock effects from a 1-MT device for ground surface overpressure ranging from 15,000 to 500 psi. As the antennae, transmitters, receivers, power supplies, and lifting mechanisms will be located within such structures, appropriate shock spectra plots were developed to determine if the fragility level of pertinent equipment will be exceeded and for use in designing shock isolation systems. Button up periods of 1 and 4 weeks were considered.

  2. Communications device identification methods, communications methods, wireless communications readers, wireless communications systems, and articles of manufacture

    DOEpatents

    Steele, Kerry D [Kennewick, WA; Anderson, Gordon A [Benton City, WA; Gilbert, Ronald W [Morgan Hill, CA

    2011-02-01

    Communications device identification methods, communications methods, wireless communications readers, wireless communications systems, and articles of manufacture are described. In one aspect, a communications device identification method includes providing identification information regarding a group of wireless identification devices within a wireless communications range of a reader, using the provided identification information, selecting one of a plurality of different search procedures for identifying unidentified ones of the wireless identification devices within the wireless communications range, and identifying at least some of the unidentified ones of the wireless identification devices using the selected one of the search procedures.

  3. Design of a communications system for multiple telemetry data channels operating simultaneously with a coherent turn-around ranging channel

    NASA Technical Reports Server (NTRS)

    Nguyen, Tien M.; Hinedi, Sami M.; Gevargiz, John M.

    1991-01-01

    This paper presents a simple technique to design a phase-modulated residual carrier communications link for optimum performance. The emphasis is on two data channels which are operated simultaneously with a ranging signal. The data channels employ PCM/PM and PCM/PSK/PM modulation schemes for high and low data rate channels, respectively. The technique proposed here selects the optimum (1) subcarrier frequency to minimize the interference between the two data channels, and (2) modulation indices for optimum balance of power between the two telemetry data channels and the coherent turn around ranging channel. The selected set of optimum modulation indices will allow for the specified bit error rate (BER) degradations in the two data channels. Although this technique is proposed to optimize the performance degradation for two data channels, generalizations can be made for more than two data channels.

  4. Automobile inspection system based on wireless communication

    NASA Astrophysics Data System (ADS)

    Miao, Changyun; Ye, Chunqing

    2010-07-01

    This paper aims to research the Automobile Inspection System based on Wireless Communication, and suggests an overall design scheme which uses GPS for speed detection and Bluetooth and GPRS for communication. The communication between PDA and PC was realized by means of GPRS and TCP/IP; and the hardware circuit and software for detection terminal were devised by means of JINOU-3264 Bluetooth Module after analyzing the Bluetooth and its communication protocol. According to the results of debugging test, this system accomplished GPRS based data communication and management as well as the real-time detection on auto safety performance parameters in crash test via PC, whereby the need for mobility and reliability was met and the efficiency and level of detection was improved.

  5. Improving Science Communication with Responsive Web Design

    NASA Astrophysics Data System (ADS)

    Hilverda, M.

    2013-12-01

    the world use low-bandwidth connections. Communicating science effectively includes efficient delivery of the information to the reader. To meet this criteria, responsive designs should also incorporate "mobile first" elements such as serving ideal image sizes (a low resolution cell phone does not need to receive a large desktop image) and a focus on fast, readable content delivery. The technical implementation of responsive web design is constantly changing as new web standards and approaches become available. However, fundamental design principles such as grid layouts, clear typography, and proper use of white space should be an important part of content delivery within any responsive design. This presentation will discuss current responsive design approaches for improving scientific communication across multiple devices, operating systems, and bandwidth capacities. The presentation will also include example responsive designs for scientific papers and websites. Implementing a responsive design approach with a focus on content and fundamental design principles is an important step to ensuring scientific information remains clear and accessible as screens and devices continue to evolve.

  6. Space Station multiple access communications system

    NASA Technical Reports Server (NTRS)

    Olson, Nanci A.

    1986-01-01

    The development of a multiple access communications system (MACS) for the space-to-space communications on the Space Station is discussed. The communications capabilities of the FHMA, CDMA, TDMA, SDMA, and FDMA techniques are evaluated; FDMA was selected for the space-to-space communications on the Space Station because of its lower complexity and growth capability. The proposed space-to-space multiple access system for the Space Station is a digitally modulated Ku-band FDMA system with a distributed architecture; this system would transmit on frequencies between 13.4 and 13.7 GHz and receive on frequencies between 14.6 and 14.89 GHz, and the bandwidth will support seven high-data-rate users and 12 low-data-rate users. The IF components and antennas for the MACS are examined. A multiple access breadboard design is described.

  7. Underground communications and tracking systems update

    SciTech Connect

    Fiscor, S.

    2008-01-15

    Today, when it comes to having systems to communicate with track and locate underground coal miners, mining companies have many equipment choices, as a direct response to the USA's 2006 MINER Act and the West Virginia Legislative Rule 56-4-8. Coal Age spoke to several companies about their leaky feeder and purely wireless systems which are either approved by the US MSHA or have been submitted for approval. The article gives details of: a UHF leaky feeder system developed by Pillar Innovations, designed to exit a mine at multiple points and then tie the leads back together on the surface; the Venture/Helicomm MineTrader system for tracking, monitoring and emergency messaging for mines; Rajant Corp.'s BreadCrumb wireless system using battery-powered wireless access nodes that enable voice and data communications across a self-healing network; the SubterraCom Wireless Solution's communications systems; a wireless mesh peer-to-peer communications system and an ultra widebade (UWB)-base real-time location tracking system from L-3 Communications; and VHF and UHF leaky feeder amplifiers from Tunnel Radio. MSHA approved communications and tracking systems are tabulated. 11 photos., 1 tab.

  8. Selling Your Design: Oral Communication Pedagogy in Design Education

    ERIC Educational Resources Information Center

    Morton, Janne; O'Brien, David

    2005-01-01

    Good design skills are the main focus of assessment practices in design education and are evaluated primarily by drawings and models. In some settings, design studio pedagogy tends to reflect only these content-oriented assessment priorities, with minimal attention paid to the development of oral communication skills. Yet, in many professional…

  9. Software-defined Quantum Communication Systems

    SciTech Connect

    Humble, Travis S; Sadlier, Ronald J

    2014-01-01

    Quantum communication systems harness modern physics through state-of-the-art optical engineering to provide revolutionary capabilities. An important concern for quantum communication engineering is designing and prototyping these systems to prototype proposed capabilities. We apply the paradigm of software-defined communica- tion for engineering quantum communication systems to facilitate rapid prototyping and prototype comparisons. We detail how to decompose quantum communication terminals into functional layers defining hardware, software, and middleware concerns, and we describe how each layer behaves. Using the super-dense coding protocol as a test case, we describe implementations of both the transmitter and receiver, and we present results from numerical simulations of the behavior. We find that while the theoretical benefits of super dense coding are maintained, there is a classical overhead associated with the full implementation.

  10. 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.

  11. NOVANET: communications network for a control system

    SciTech Connect

    Hill, J.R.; Severyn, J.R.; VanArsdall, P.J.

    1983-05-23

    NOVANET is a control system oriented fiber optic local area network that was designed to meet the unique and often conflicting requirements of the Nova laser control system which will begin operation in 1984. The computers and data acquisition devices that form the distributed control system for a large laser fusion research facility need reliable, high speed communications. Both control/status messages and experimental data must be handled. A subset of NOVANET is currently operating on the two beam Novette laser system.

  12. Spacecraft design project: Low Earth orbit communications satellite

    NASA Technical Reports Server (NTRS)

    Moroney, Dave; Lashbrook, Dave; Mckibben, Barry; Gardener, Nigel; Rivers, Thane; Nottingham, Greg; Golden, Bill; Barfield, Bill; Bruening, Joe; Wood, Dave

    1991-01-01

    This is the final product of the spacecraft design project completed to fulfill the academic requirements of the Spacecraft Design and Integration 2 course (AE-4871) taught at the U.S. Naval Postgraduate School. The Spacecraft Design and Integration 2 course is intended to provide students detailed design experience in selection and design of both satellite system and subsystem components, and their location and integration into a final spacecraft configuration. The design team pursued a design to support a Low Earth Orbiting (LEO) communications system (GLOBALSTAR) currently under development by the Loral Cellular Systems Corporation. Each of the 14 team members was assigned both primary and secondary duties in program management or system design. Hardware selection, spacecraft component design, analysis, and integration were accomplished within the constraints imposed by the 11 week academic schedule and the available design facilities.

  13. Advanced satellite communication system

    NASA Technical Reports Server (NTRS)

    Staples, Edward J.; Lie, Sen

    1992-01-01

    The objective of this research program was to develop an innovative advanced satellite receiver/demodulator utilizing surface acoustic wave (SAW) chirp transform processor and coherent BPSK demodulation. The algorithm of this SAW chirp Fourier transformer is of the Convolve - Multiply - Convolve (CMC) type, utilizing off-the-shelf reflective array compressor (RAC) chirp filters. This satellite receiver, if fully developed, was intended to be used as an on-board multichannel communications repeater. The Advanced Communications Receiver consists of four units: (1) CMC processor, (2) single sideband modulator, (3) demodulator, and (4) chirp waveform generator and individual channel processors. The input signal is composed of multiple user transmission frequencies operating independently from remotely located ground terminals. This signal is Fourier transformed by the CMC Processor into a unique time slot for each user frequency. The CMC processor is driven by a waveform generator through a single sideband (SSB) modulator. The output of the coherent demodulator is composed of positive and negative pulses, which are the envelopes of the chirp transform processor output. These pulses correspond to the data symbols. Following the demodulator, a logic circuit reconstructs the pulses into data, which are subsequently differentially decoded to form the transmitted data. The coherent demodulation and detection of BPSK signals derived from a CMC chirp transform processor were experimentally demonstrated and bit error rate (BER) testing was performed. To assess the feasibility of such advanced receiver, the results were compared with the theoretical analysis and plotted for an average BER as a function of signal-to-noise ratio. Another goal of this SBIR program was the development of a commercial product. The commercial product developed was an arbitrary waveform generator. The successful sales have begun with the delivery of the first arbitrary waveform generator.

  14. 47 CFR 90.465 - Control of systems of communication.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 47 Telecommunication 5 2010-10-01 2010-10-01 false Control of systems of communication. 90.465 Section 90.465 Telecommunication FEDERAL COMMUNICATIONS COMMISSION (CONTINUED) SAFETY AND SPECIAL RADIO SERVICES PRIVATE LAND MOBILE RADIO SERVICES Transmitter Control § 90.465 Control of systems of communication. (a) Depending on design...

  15. Communication design for multi-boards based on VME bus

    NASA Astrophysics Data System (ADS)

    Liu, Yang; Song, Fazhi; Wei, Kai; Fu, Zhenxian

    2015-02-01

    As a widely used open-architecture computer bus ,VME bus is increasingly applied in military, aerospace, transportation and other large-scale control systems. Lithography, a very delicate and complicated integrated circuit manufacturing equipment, uses many circuit boards with VME interface in its control system, including one single-board computer, many movement control boards and one data acquisition board. This paper designs communication modules which include VME bus module and VME user-defined bus module for multi-boards in Lithography control system. VME bus module is designed for the communication between the single-board computer and movement control boards and VME user-defined bus is designed for the communication between movement control boards and data acquisition board. The experimental results demonstrate its effectiveness.

  16. Communication by Design. A Public Relations Handbook.

    ERIC Educational Resources Information Center

    Illinois State Board of Education, Springfield. Dept. of Adult, Vocational and Technical Education.

    This handbook provides information and forms for conducting successful public relations activities for vocational education. Chapter 1 discusses the importance of planning. The research, consultation, objective, and plan design phases are covered. Chapter 2 is an original discourse on communications theory with identification of crucial elements…

  17. 33 CFR 127.1111 - Communication systems.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 33 Navigation and Navigable Waters 2 2014-07-01 2014-07-01 false Communication systems. 127.1111 Section 127.1111 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED... Waterfront Facilities Handling Liquefied Hazardous Gas Design and Construction § 127.1111...

  18. 33 CFR 127.1111 - Communication systems.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 33 Navigation and Navigable Waters 2 2012-07-01 2012-07-01 false Communication systems. 127.1111 Section 127.1111 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED... Waterfront Facilities Handling Liquefied Hazardous Gas Design and Construction § 127.1111...

  19. 33 CFR 127.1111 - Communication systems.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 33 Navigation and Navigable Waters 2 2013-07-01 2013-07-01 false Communication systems. 127.1111 Section 127.1111 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED... Waterfront Facilities Handling Liquefied Hazardous Gas Design and Construction § 127.1111...

  20. The picture exchange communication system.

    PubMed

    Bondy, A S; Frost, L A

    1998-01-01

    The Picture Exchange Communication System (PECS) was developed as a means to teach children with autism and related developmental disabilities a rapidly acquired, self-initiating, functional communication system. Its theoretical roots combine principles from applied behavior analysis and guidelines established within the field of alternative and augmentative communication. This approach has several potential advantages relative to imitation-based strategies (both vocal and gestural) and symbol selection strategies. The system begins with the exchange of simple icons but rapidly builds "sentence" structure. The system also emphasizes developing the request function prior to developing responding to simple questions and commenting. The development of requesting with a sentence structure also permits the rapid development of attributes more traditionally taught within a receptive mode. The relationship between the introduction of PECS and various other behavioral issues (i.e., social approach and behavior management) as well as its relationship to the codevelopment of speech are reviewed. PMID:9857393

  1. A Shuttle based laser system for space communication

    NASA Technical Reports Server (NTRS)

    Fitzmaurice, Michael W.; Bruno, Ronald C.

    1988-01-01

    A key element of NASA-Goddard's plan for future laser space communications is the Space Shuttle-based Laser Technology Experiments Facility (LTEF), which will be designed to communicate with a cooperative laser system under development for the Advanced Communication Technology Satellite (ACTS) and will conduct a comprehensive set of acquisition, tracking, and communication experiments. Attention is presently given to the challenges faced by designers in achieving LTEF acquisition of the ACTS downlink beacon laser.

  2. The PLATO IV Communications System.

    ERIC Educational Resources Information Center

    Sherwood, Bruce Arne; Stifle, Jack

    The PLATO IV computer-based educational system contains its own communications hardware and software for operating plasma-panel graphics terminals. Key echoing is performed by the central processing unit: every key pressed at a terminal passes through the entire system before anything appears on the terminal's screen. Each terminal is guaranteed…

  3. Laser communication experiment. Volume 1: Design study report: Spacecraft transceiver. Part 3: LCE design specifications

    NASA Technical Reports Server (NTRS)

    1970-01-01

    The requirements for the design, fabrication, performance, and testing of a 10.6 micron optical heterodyne receiver subsystem for use in a laser communication system are presented. The receiver subsystem, as a part of the laser communication experiment operates in the ATS 6 satellite and in a transportable ground station establishing two-way laser communications between the spacecraft and the transportable ground station. The conditions under which environmental tests are conducted are reported.

  4. A small terminal for satellite communication systems

    NASA Technical Reports Server (NTRS)

    Xiong, Fuqin; Wu, Dong; Jin, Min

    1994-01-01

    A small portable, low-cost satellite communications terminal system incorporating a modulator/demodulator and convolutional-Viterbi coder/decoder is described. Advances in signal processing and error-correction techniques in combination with higher power and higher frequencies aboard satellites allow for more efficient use of the space segment. This makes it possible to design small economical earth stations. The Advanced Communications Technology Satellite (ACTS) was chosen to test the system. ACTS, operating at the Ka band incorporates higher power, higher frequency, frequency and spatial reuse using spot beams and polarization.

  5. 33 CFR 127.111 - Communications systems.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... transfer area for LNG must have a ship-to-shore communication system and a separate emergency ship-to-shore communication system. (b) Each ship-to-shore communication system must be a dedicated system that allows voice communication between the person in charge of transfer operations on the vessel, the person in charge...

  6. Visual Communication Design as a Form of Public Pedagogy

    ERIC Educational Resources Information Center

    Kelly, Meghan

    2015-01-01

    This paper identifies visual communication design as a form of public pedagogy. Communication design practices aim to achieve the successful transmission of a message to a recipient in a visual mode. Understanding the theories and practices of visual communication design can assist in enhancing the reception of the communication, as these…

  7. Time reversal communication system

    DOEpatents

    Candy, James V.; Meyer, Alan W.

    2008-12-02

    A system of transmitting a signal through a channel medium comprises digitizing the signal, time-reversing the digitized signal, and transmitting the signal through the channel medium. The channel medium may be air, earth, water, tissue, metal, and/or non-metal.

  8. Rapidly deployable emergency communication system

    DOEpatents

    Gladden, Charles A.; Parelman, Martin H.

    1979-01-01

    A highly versatile, highly portable emergency communication system which permits deployment in a very short time to cover both wide areas and distant isolated areas depending upon mission requirements. The system employs a plurality of lightweight, fully self-contained repeaters which are deployed within the mission area to provide communication between field teams, and between each field team and a mobile communication control center. Each repeater contains a microcomputer controller, the program for which may be changed from the control center by the transmission of digital data within the audible range (300-3,000 Hz). Repeaters are accessed by portable/mobile transceivers, other repeaters, and the control center through the transmission and recognition of digital data code words in the subaudible range.

  9. Shuttle orbiter Ku-band radar/communications system design evaluation: High gain antenna/widebeam horn

    NASA Technical Reports Server (NTRS)

    Iwasaki, R.; Dodds, J. G.; Broad, P.

    1979-01-01

    The physical characteristics of the high gain antenna reflector and feed elements are described. Deficiencies in the sum feed are discussed, and lack of atmospheric venting is posed as a potential problem area. The measured RF performance of the high gain antenna is examined and the high sidelobe levels measured are related to the physical characteristics of the antenna. An examination of the attributes of the feed which might be influenced by temperature extremes shows that the antenna should be insensitive to temperature variations. Because the feed support bipod structure is considered a significant contributor to the high sidelobe levels measured in the azimuth plane, pod relocation, material changes, and shaping are suggested as improvements. Alternate feed designs are presented to further improve system performance. The widebeam horn and potential temperature effects due to the polarizer are discussed as well as in the effects of linear polarization on TDRS acquisition, and the effects of circular polarization on radar sidelobe avoidance. The radar detection probability is analyzed as a function of scan overlap and target range.

  10. Coherent OCDMA communication systems

    NASA Astrophysics Data System (ADS)

    Wang, Xu

    2012-01-01

    Coherent optical code division multiple access (OCDMA) technique, where encoding and decoding are based on the phase and amplitude of optical field instead of its intensity, is receiving much attention for the overall superior performance over incoherent OCDMA and the development of compact and reliable en/decoders (E/D) such as spatial light phase modulator (SLPM), superstructured fiber Bragg grating (SSFBG) and multi-port array waveguide grating (AWG)-type E/D. In this paper, we will discuss several recent progresses in coherent OCDMA: a. Novel coding technology such as multi-phase-level SSFBG encoder, 50x50 multiport en/decoder and reconfigurable time domain spectral phase en/decoding; b. New signal modulation formats in OCDMA including DPSK, DQPSK, CSK and M-ary CSK; and c. Field trials of high capacity WDM/OCDMA systems.

  11. 49 CFR 193.2519 - Communication systems.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 49 Transportation 3 2010-10-01 2010-10-01 false Communication systems. 193.2519 Section 193.2519...: FEDERAL SAFETY STANDARDS Operations § 193.2519 Communication systems. (a) Each LNG plant must have a primary communication system that provides for verbal communications between all operating personnel...

  12. 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.

  13. Designing Scalable PGAS Communication Subsystems on Cray Gemini Interconnect

    SciTech Connect

    Vishnu, Abhinav; Daily, Jeffrey A.; Palmer, Bruce J.

    2012-12-26

    The Cray Gemini Interconnect has been recently introduced as a next generation network architecture for building multi-petaflop supercomputers. Cray XE6 systems including LANL Cielo, NERSC Hopper, ORNL Titan and proposed NCSA BlueWaters leverage the Gemini Interconnect as their primary Interconnection network. At the same time, programming models such as the Message Passing Interface (MPI) and Partitioned Global Address Space (PGAS) models such as Unified Parallel C (UPC) and Co-Array Fortran (CAF) have become available on these systems. Global Arrays is a popular PGAS model used in a variety of application domains including hydrodynamics, chemistry and visualization. Global Arrays uses Aggregate Re- mote Memory Copy Interface (ARMCI) as the communication runtime system for Remote Memory Access communication. This paper presents a design, implementation and performance evaluation of scalable and high performance communication subsystems on Cray Gemini Interconnect using ARMCI. The design space is explored and time-space complexities of commu- nication protocols for one-sided communication primitives such as contiguous and uniformly non-contiguous datatypes, atomic memory operations (AMOs) and memory synchronization is presented. An implementation of the proposed design (referred as ARMCI-Gemini) demonstrates the efficacy on communication primitives, application kernels such as LU decomposition and full applications such as Smooth Particle Hydrodynamics (SPH) application.

  14. Facilitating Designer-Customer Communication in the World Wide Web.

    ERIC Educational Resources Information Center

    Tuikka, Tuomo; Salmela, Marko

    1998-01-01

    Presents WebShaman, an application built to demonstrate how a distributed virtual prototyping system with a client/server architecture, could support geographically distant designer/customer communication. Provides an overview of smart virtual prototyping; discusses implementation of synchronous collaboration via the World Wide Web; and assesses…

  15. Communications network design and costing model programmers manual

    NASA Technical Reports Server (NTRS)

    Logan, K. P.; Somes, S. S.; Clark, C. A.

    1983-01-01

    Otpimization algorithms and techniques used in the communications network design and costing model for least cost route and least cost network problems are examined from the programmer's point of view. All system program modules, the data structures within the model, and the files which make up the data base are described.

  16. 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.

  17. DCS/FTS Commercial Satellite Communications System

    NASA Astrophysics Data System (ADS)

    Shimabukuro, T.; Rosner, R.; Pearsall, C.

    In order to control the rising costs of telephonic services and meeting the increasing demand for wideband video and data services within U.S. Federal Government agencies, the Defense Communications Agency and the General Services Administration have begun the implementation of a leased Commercial Satellite Communications System. Service volume demand, commonality of service requirements, and common geographic communities of interest facilitate economies of scale in the course of meeting DOD and other Federal agencies' objectives. The service, which incorporates the Federal Telecommunications Service and is therefore designated DCS/FTS, is presently studied with respect to military and national objectives.

  18. The Intelsat digital communication systems

    NASA Astrophysics Data System (ADS)

    Phiel, John F., Jr.

    1990-08-01

    Intelsat international communication services resulting from the application of digital technology are summarized. Approximately 40 percent of the 140,000 terrestrial channels from the Public Switched Telephone Networks (PSTN) provided by the Intelsat network are now handled by digital systems. Digital technology for the interconnection of the PSTNs is discussed. Particular attention is paid to modulation and access techniques including the intermediate data rate (IDR) system, and the fixed and satellite switched TDMA systems. Digital compression techniques used with TDMA and IDR, such as digital speech interpolation and digital circuit multiplication, are also discussed. The Intelsat Business Service and the Intelnet Service are described in the framework of digital technology for private networks and business users. Communications for remote areas, international television services, and future opportunities through digital technologies are briefly presented.

  19. Design of interstellar digital communication links: Some insights from communication engineering

    NASA Astrophysics Data System (ADS)

    Messerschmitt, David G.; Morrison, Ian S.

    2012-09-01

    The design of an end-to-end digital interstellar communication system at radio frequencies is discussed, drawing on the disciplines of digital communication engineering and computer network engineering in terrestrial and near-space applications. One goal is a roadmap to the design of such systems, aimed at future designers of either receivers (SETI) or transmitters (METI). In particular we emphasize the implications arising from the impossibility of coordination between transmitter and receiver prior to a receiver's search for a signal. A system architecture based on layering, as commonly used in network and software design, assists in organizing and categorizing the various design issues and identifying dependencies. Implications of impairments introduced in the interstellar medium, such as dispersion, scattering, Doppler, noise, and signal attenuation are discussed. Less fundamental (but nevertheless influential) design issues are the motivations of the transmitter designers and associated resource requirements at both transmitter and receiver. Unreliability is inevitably imposed by non-idealities in the physical communication channel, and this unreliability will have substantial implications for those seeking to convey interstellar messages.

  20. Design Reference Missions for Deep-Space Optical Communication

    NASA Astrophysics Data System (ADS)

    Breidenthal, J.; Abraham, D.

    2016-05-01

    We examined the potential, but uncertain, NASA mission portfolio out to a time horizon of 20 years, to identify mission concepts that potentially could benefit from optical communication, considering their communications needs, the environments in which they would operate, and their notional size, weight, and power constraints. A set of 12 design reference missions was selected to represent the full range of potential missions. These design reference missions span the space of potential customer requirements, and encompass the wide range of applications that an optical ground segment might eventually be called upon to serve. The design reference missions encompass a range of orbit types, terminal sizes, and positions in the solar system that reveal the chief system performance variables of an optical ground segment, and may be used to enable assessments of the ability of alternative systems to meet various types of customer needs.

  1. On Optimal Input Design and Model Selection for Communication Channels

    SciTech Connect

    Li, Yanyan; Djouadi, Seddik M; Olama, Mohammed M

    2013-01-01

    In this paper, the optimal model (structure) selection and input design which minimize the worst case identification error for communication systems are provided. The problem is formulated using metric complexity theory in a Hilbert space setting. It is pointed out that model selection and input design can be handled independently. Kolmogorov n-width is used to characterize the representation error introduced by model selection, while Gel fand and Time n-widths are used to represent the inherent error introduced by input design. After the model is selected, an optimal input which minimizes the worst case identification error is shown to exist. In particular, it is proven that the optimal model for reducing the representation error is a Finite Impulse Response (FIR) model, and the optimal input is an impulse at the start of the observation interval. FIR models are widely popular in communication systems, such as, in Orthogonal Frequency Division Multiplexing (OFDM) systems.

  2. Integrated Formation Optical Communication and Estimation System

    NASA Technical Reports Server (NTRS)

    Scharf, Daniel; Kuhnert, Andreas; Kovalik, Joseph; Hadaegh, Fred; Shaddock, Daniel

    2008-01-01

    An architecture has been designed that integrates formation estimation methodologies, precision formation sensing, and high-bandwidth formation communication into a robust, strap-on system that meets knowledge and communication requirements for the majority of planned, precision formation missions. Specifically, the integrated system supports (a) sub-millimeter metrology, (b) multiple greater than 10 Mbps communication channels over a large, 10 deg field-of-view (FOV), and (c) generalized formation estimation methodologies. The sensing sub-system consists of several absolute, metrology gauges with up to 0.1 mm precision that use amplitude-modulated lasers and a LISA-heritage phase meter. Since amplitude modulation is used, inexpensive and robust diode lasers may be used instead of complex, frequency-stabilized lasers such as for nanometer-level metrology. The metrology subsystem laser transceivers consist of a laser diode, collecting optics, and an avalanche photo diode (APD) for detecting incoming laser signals. The APD is necessary since received power is small due to the large (for optical applications) FOV. The phase meter determines the phase of the incoming amplitude modulations as measured by the APD. This phase is equivalent to time-of-flight and, therefore, distance. By placing three laser transceivers on each spacecraft, 18 clock-offset-corrupted distances are calculated. These measurements are communicated and averaged to obtain nine correct distances between the transceivers. From these correct distances, the range and bearing between spacecraft and their relative attitude are determined. Next, communication is integrated on the laser carrier through spectral separation. Metrology amplitude modulations are limited to the 45-50 MHz band, leaving 0-45 MHz for communication. Through careful design of coding scheme, error correction, and filters, six independent 10 Mbps receive channels are possible. Hence, a spacecraft can simultaneously broadcast at 10

  3. Shuttle orbiter Ku-band radar/communications system design evaluation. Ku band bent-pipe channel performance evaluation

    NASA Technical Reports Server (NTRS)

    Holmes, J. K.; Dodds, J. G.

    1980-01-01

    Because of difficulties with the bit detector of the SPA mode 1 channel 3 input port, a new bit synchronizer was required. The two prime candidate designs are described and analyzed. The selected design is a modification of one which utilizes a phase frequency detector to track the received data clock frequency and a mid-bit transition point sample detector to generate a bit timing error (phase error) signal to control the relative phase between the local clock and the local data stream. The model used to calculate the effects of cable attenuation and rise time degradation is discussed.

  4. Cavity-Dumped Communication Laser Design

    NASA Technical Reports Server (NTRS)

    Roberts, W. T.

    2003-01-01

    Cavity-dumped lasers have significant advantages over more conventional Q-switched lasers for high-rate operation with pulse position modulation communications, including the ability to emit laser pulses at 1- to 10-megahertz rates, with pulse widths of 0.5 to 5 nanoseconds. A major advantage of cavity dumping is the potential to vary the cavity output percentage from pulse to pulse, maintaining the remainder of the energy in reserve for the next pulse. This article presents the results of a simplified cavity-dumped laser model, establishing the requirements for cavity efficiency and projecting the ultimate laser efficiency attainable in normal operation. In addition, a method of reducing or eliminating laser dead time is suggested that could significantly enhance communication capacity. The design of a laboratory demonstration laser is presented with estimates of required cavity efficiency and demonstration potential.

  5. Low Altitude Space Communication System

    NASA Astrophysics Data System (ADS)

    Namiki, Michiyoshi; Matsuzaka, Yukihiko; Honda, Hideyuki; Toriumi, Michihiko; Kamioka, Eiji; Saito, Yoshitaka; Izutsu, Naoki; Ohta, Sigeo; Yamagami, Takamasa; Yajima, Nobuyuki; Hirosawa, Haruto; Ohya, Nobuhiko; Takezawa, Fukashi; Yamaguchi, Kenji

    We describe a new Low Altitude Space Communication System (LASCOS), which was completed in 1996 by the Institute of Space and Astronautical Science in Japan. This system consists of a mobile balloon tracking and receiving station and networks which connect them to the Sanriku Balloon Center in Iwate Municipality and the Institute of Space and Astronautical Science (ISAS) in Kanagawa Municipality. This station and the SBC receiving station are connected via telephone lines, i. e. an Integrated Services Digital Network (ISDN) or an analog communication network. Balloon trajectory monitoring, telecommand transmission operation and telemetry data acquisition can be done from any computer terminal through the LASCOS. LASCOS has built-in flexibility to adapt to a foreign balloon station. The number of individuals necessary to operate it minimum. LASCOS will be used for long range tracking and balloon expedition. We present the results of its first test with an actual balloon flight

  6. A systems approach to animal communication

    PubMed Central

    Barron, Andrew B.; Balakrishnan, Christopher N.; Hauber, Mark E.; Hoke, Kim L.

    2016-01-01

    Why animal communication displays are so complex and how they have evolved are active foci of research with a long and rich history. Progress towards an evolutionary analysis of signal complexity, however, has been constrained by a lack of hypotheses to explain similarities and/or differences in signalling systems across taxa. To address this, we advocate incorporating a systems approach into studies of animal communication—an approach that includes comprehensive experimental designs and data collection in combination with the implementation of systems concepts and tools. A systems approach evaluates overall display architecture, including how components interact to alter function, and how function varies in different states of the system. We provide a brief overview of the current state of the field, including a focus on select studies that highlight the dynamic nature of animal signalling. We then introduce core concepts from systems biology (redundancy, degeneracy, pluripotentiality, and modularity) and discuss their relationships with system properties (e.g. robustness, flexibility, evolvability). We translate systems concepts into an animal communication framework and accentuate their utility through a case study. Finally, we demonstrate how consideration of the system-level organization of animal communication poses new practical research questions that will aid our understanding of how and why animal displays are so complex. PMID:26936240

  7. 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.

  8. 33 CFR 127.1111 - Communication systems.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... systems. (a) The marine transfer area for LHG must possess a communication system that enables continuous... in charge of transfer for the facility. (b) The communication system required by paragraph (a) of... 33 Navigation and Navigable Waters 2 2011-07-01 2011-07-01 false Communication systems....

  9. Economics of satellite communications systems

    NASA Astrophysics Data System (ADS)

    Pritchard, Wilbur L.

    This paper is partly a tutorial, telling systematically how one goes about calculating the total annual costs of a satellite communications system, and partly the expression of some original ideas on the choice of parameters so as to minimize these costs. The calculation of costs can be divided into two broad categories. The first is technical and is concerned with estimating what particular equipment will cost and what will be the annual expense to maintain and operate it. One starts in the estimation of any new system by listing the principal items of equipment, such as satellites, earth stations of various sizes and functions, telemetry and tracking equipment and terrestrial interfaces, and then estimating how much each item will cost. Methods are presented for generating such estimates, based on a knowledge of the gross parameters, such as antenna size, coverage area, transmitter power and information rate. These parameters determine the system performance and it is usually possible, knowing them, to estimate the costs of the equipment rather well. Some formulae based on regression analyses are presented. Methods are then given for estimating closely related expenses, such as maintenance and operation, and then an approximate method is developed for estimating terrestrial interconnection costs. It is pointed out that in specific cases when tariff and geographical information are available, it is usually better to work with specific data, but nonetheless it is often desirable, especially in global system estimating, to approximate these interconnect costs without recourse to individual tariffs. The procedure results in a set of costs for the purchase of equipment and its maintenance, and a schedule of payments. Some payments will be incurred during the manufacture of the satellite and before any systems operation, but many will not be incurred until the system is no longer in use, e.g. incentives. In any case, with the methods presented in the first section, one

  10. Communications Systems for Mobile Robotics

    SciTech Connect

    Futterman, J A; Pao, H

    2003-12-08

    Performance Confirmation is the activity by which the Yucca Mountain Project confirms that the engineered and natural containment barriers of this national nuclear waste repository are performing as predicted, so that an eventual decision to close the repository can be made. This activity involves systems that must be inspected and, in some cases, serviced by mobile robots. This paper discusses systems for underground mobile robot communications, including requirements, environments, options, issues, and down-select criteria. We reviewed a variety of systems, including Slotted Waveguide, Powerline Carrier, Leaky Feeder, Photonic Bandgap Fiber, Free-Space Optics, Millimeter Waves, Terahertz Systems, and RF Systems (including IEEE 802.11 a,b, and g, and Ultra-Wideband radio).

  11. An orbital angular momentum radio communication system optimized by intensity controlled masks effectively: Theoretical design and experimental verification

    NASA Astrophysics Data System (ADS)

    Gao, Xinlu; Huang, Shanguo; Wei, Yongfeng; Zhai, Wensheng; Xu, Wenjing; Yin, Shan; Zhou, Jing; Gu, Wanyi

    2014-12-01

    A system of generating and receiving orbital angular momentum (OAM) radio beams, which are collectively formed by two circular array antennas (CAAs) and effectively optimized by two intensity controlled masks, is proposed and experimentally investigated. The scheme is effective in blocking of the unwanted OAM modes and enhancing the power of received radio signals, which results in the capacity gain of system and extended transmission distance of the OAM radio beams. The operation principle of the intensity controlled masks, which can be regarded as both collimator and filter, is feasible and simple to realize. Numerical simulations of intensity and phase distributions at each key cross-sectional plane of the radio beams demonstrate the collimated results. The experimental results match well with the theoretical analysis and the receive distance of the OAM radio beam at radio frequency (RF) 20 GHz is extended up to 200 times of the wavelength of the RF signals, the measured distance is 5 times of the original measured distance. The presented proof-of-concept experiment demonstrates the feasibility of the system.

  12. An orbital angular momentum radio communication system optimized by intensity controlled masks effectively: Theoretical design and experimental verification

    SciTech Connect

    Gao, Xinlu; Huang, Shanguo Wei, Yongfeng; Zhai, Wensheng; Xu, Wenjing; Yin, Shan; Gu, Wanyi; Zhou, Jing

    2014-12-15

    A system of generating and receiving orbital angular momentum (OAM) radio beams, which are collectively formed by two circular array antennas (CAAs) and effectively optimized by two intensity controlled masks, is proposed and experimentally investigated. The scheme is effective in blocking of the unwanted OAM modes and enhancing the power of received radio signals, which results in the capacity gain of system and extended transmission distance of the OAM radio beams. The operation principle of the intensity controlled masks, which can be regarded as both collimator and filter, is feasible and simple to realize. Numerical simulations of intensity and phase distributions at each key cross-sectional plane of the radio beams demonstrate the collimated results. The experimental results match well with the theoretical analysis and the receive distance of the OAM radio beam at radio frequency (RF) 20 GHz is extended up to 200 times of the wavelength of the RF signals, the measured distance is 5 times of the original measured distance. The presented proof-of-concept experiment demonstrates the feasibility of the system.

  13. Communications and control for electric power systems

    NASA Technical Reports Server (NTRS)

    Kirkham, H.; Goettsche, A.; Niebur, D.; Friend, H.; Johnston, A.

    1991-01-01

    The first section of the report describes the AbNET system, a hardware and software communications system designed for distribution automation (it can also find application in substation monitoring and control). The topology of the power system fixes the topology of the communications network, which can therefore be expected to include a larger number of branch points, tap points, and interconnections. These features make this communications network unlike any other. The network operating software has to solve the problem of communicating to all the nodes of a very complex network in as reliable a way as possible even if the network is damaged, and it has to do so with minimum transmission delays and at minimum cost. The design of the operating protocols is described within the framework of the seven-layer Open System Interconnection hierarchy of the International Standards Organization. Section 2 of the report describes the development and testing of a high voltage sensor based on an electro-optic polymer. The theory of operation is reviewed. Bulk fabrication of the polymer is discussed, as well as results of testing of the electro-optic coefficient of the material. Fabrication of a complete prototype sensor suitable for use in the range 1-20 kV is described. The electro-optic polymer is shown to be an important material for fiber optic sensing applications. Appendix A is theoretical support for this work. The third section of the report presents the application of an artificial neural network, Kohonen's self-organizing feature map, for the classification of power system states. This classifier maps vectors of an N-dimensional space to a 2-dimensional neural net in a nonlinear way preserving the topological order of the input vectors. These mappings are studied using a nonlinear power system model.

  14. 33 CFR 127.111 - Communications systems.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 33 Navigation and Navigable Waters 2 2010-07-01 2010-07-01 false Communications systems. 127.111... Waterfront Facilities Handling Liquefied Natural Gas § 127.111 Communications systems. (a) The marine transfer area for LNG must have a ship-to-shore communication system and a separate emergency...

  15. Communication System Architecture for Planetary Exploration

    NASA Technical Reports Server (NTRS)

    Braham, Stephen P.; Alena, Richard; Gilbaugh, Bruce; Glass, Brian; Norvig, Peter (Technical Monitor)

    2001-01-01

    Future human missions to Mars will require effective communications supporting exploration activities and scientific field data collection. Constraints on cost, size, weight and power consumption for all communications equipment make optimization of these systems very important. These information and communication systems connect people and systems together into coherent teams performing the difficult and hazardous tasks inherent in planetary exploration. The communication network supporting vehicle telemetry data, mission operations, and scientific collaboration must have excellent reliability, and flexibility.

  16. Communications satellite system for Africa

    NASA Astrophysics Data System (ADS)

    Kriegl, W.; Laufenberg, W.

    1980-09-01

    Earlier established requirement estimations were improved upon by contacting African administrations and organizations. An enormous demand is shown to exist for telephony and teletype services in rural areas. It is shown that educational television broadcasting should be realized in the current African transport and communications decade (1978-1987). Radio broadcasting is proposed in order to overcome illiteracy and to improve educational levels. The technical and commercial feasibility of the system is provided by computer simulations which demonstrate how the required objectives can be fulfilled in conjunction with ground networks.

  17. Iridium{reg_sign} worldwide personal communication system

    SciTech Connect

    Helm, J.

    1997-01-01

    The IRIDIUM system is a personal worldwide communication system designed to support portable, low power subscriber units through the use of a constellation of satellites in low earth polar orbit. The satellites are networked together to form a system which provides continuous line-of-sight communications between the IRIDIUM system and any point within 30 km of the earth{close_quote}s surface. The system architecture and operation are described. {copyright} {ital 1997 American Institute of Physics.}

  18. Radio propagation for space communications systems

    NASA Technical Reports Server (NTRS)

    Ippolito, L. J.

    1981-01-01

    This paper presents a review of the most recent information on the effects of the earth's atmosphere on space communications systems. Models and techniques used in the prediction of atmospheric effects as influenced by frequency, geography, elevation angle, and type of transmission are discussed. Recent data on performance characteristics obtained from direct measurements on satellite links operating to above 30 GHz are reviewed. Particular emphasis is placed on the effects of precipitation on the earth-space path, including rain attenuation, and rain and ice-particle depolarization. Sky noise, antenna gain degradation, scintillations, and bandwidth coherence are also discussed. The impact of the various propagation factors on communications system design criteria is presented. These criteria include link reliability, power margins, noise contributions, modulation and polarization factors, channel crosstalk, error-rate, and bandwidth limitations.

  19. The 'INMARSAT' international maritime satellite communication system

    NASA Astrophysics Data System (ADS)

    Atserov, Iu. S.

    1982-12-01

    The history, design, operating characteristics, achievements, and prospects of INMARSAT are discussed. More than 1300 ships are presently equipped to operate within the system, and this number is expected to rise to about 5000 by 1986. The principle of operation involves single coordinating earth stations allocating telephone channels in their zones between other earth stations. The messages reach a common signalling channel with which all ship stations keep in touch. The ship stations are connected to the international telex network. The INMARSAT system enables ships in the automated mode of operation to establish telephone and telegraph comunication with any subscriber on the shore of any country. The quality of the communication is practically independent of the distance between ship and shore at any time of year and under any meteorological conditions. Estimates indicate that the use of satellite communication with ships reduces losses from accidents by 10 percent per year.

  20. Wireless Augmented Reality Communication System

    NASA Technical Reports Server (NTRS)

    Devereaux, Ann (Inventor); Jedrey, Thomas (Inventor); Agan, Martin (Inventor)

    2014-01-01

    The system of the present invention is a highly integrated radio communication system with a multimedia co-processor which allows true two-way multimedia (video, audio, data) access as well as real-time biomedical monitoring in a pager-sized portable access unit. The system is integrated in a network structure including one or more general purpose nodes for providing a wireless-to-wired interface. The network architecture allows video, audio and data (including biomedical data) streams to be connected directly to external users and devices. The portable access units may also be mated to various non-personal devices such as cameras or environmental sensors for providing a method for setting up wireless sensor nets from which reported data may be accessed through the portable access unit. The reported data may alternatively be automatically logged at a remote computer for access and viewing through a portable access unit, including the user's own.

  1. Wireless augmented reality communication system

    NASA Technical Reports Server (NTRS)

    Devereaux, Ann (Inventor); Jedrey, Thomas (Inventor); Agan, Martin (Inventor)

    2006-01-01

    The system of the present invention is a highly integrated radio communication system with a multimedia co-processor which allows true two-way multimedia (video, audio, data) access as well as real-time biomedical monitoring in a pager-sized portable access unit. The system is integrated in a network structure including one or more general purpose nodes for providing a wireless-to-wired interface. The network architecture allows video, audio and data (including biomedical data) streams to be connected directly to external users and devices. The portable access units may also be mated to various non-personal devices such as cameras or environmental sensors for providing a method for setting up wireless sensor nets from which reported data may be accessed through the portable access unit. The reported data may alternatively be automatically logged at a remote computer for access and viewing through a portable access unit, including the user's own.

  2. Design for minimum energy in interstellar communication

    NASA Astrophysics Data System (ADS)

    Messerschmitt, David G.

    2015-02-01

    Microwave digital communication at interstellar distances is the foundation of extraterrestrial civilization (SETI and METI) communication of information-bearing signals. Large distances demand large transmitted power and/or large antennas, while the propagation is transparent over a wide bandwidth. Recognizing a fundamental tradeoff, reduced energy delivered to the receiver at the expense of wide bandwidth (the opposite of terrestrial objectives) is advantageous. Wide bandwidth also results in simpler design and implementation, allowing circumvention of dispersion and scattering arising in the interstellar medium and motion effects and obviating any related processing. The minimum energy delivered to the receiver per bit of information is determined by cosmic microwave background alone. By mapping a single bit onto a carrier burst, the Morse code invented for the telegraph in 1836 comes closer to this minimum energy than approaches used in modern terrestrial radio. Rather than the terrestrial approach of adding phases and amplitudes increases information capacity while minimizing bandwidth, adding multiple time-frequency locations for carrier bursts increases capacity while minimizing energy per information bit. The resulting location code is simple and yet can approach the minimum energy as bandwidth is expanded. It is consistent with easy discovery, since carrier bursts are energetic and straightforward modifications to post-detection pattern recognition can identify burst patterns. Time and frequency coherence constraints leading to simple signal discovery are addressed, and observations of the interstellar medium by transmitter and receiver constrain the burst parameters and limit the search scope.

  3. Do Animal Communication Systems Have Phonemes?

    PubMed

    Bowling, Daniel L; Fitch, W Tecumseh

    2015-10-01

    Biologists often ask whether animal communication systems make use of conceptual entities from linguistics, such as semantics or syntax. A new study of an Australian bird species argues that their communication system has phonemes, but we argue that imposing linguistic concepts obscures, rather than clarifyies, communicative function. PMID:26346993

  4. Complex Communication System and Social Change.

    ERIC Educational Resources Information Center

    Chang, Won H.

    The basic question under examination is the underlying force that brings forth changes in cultural and social organizations. By employing general system theory and communication systemic analysis, the author concludes that communication, especially human communication, is the main vehicle of change. Human interchange, it is suggested, is constant…

  5. Shuttle orbiter S-band communications equipment design evaluation

    NASA Technical Reports Server (NTRS)

    Springett, J. C.

    1979-01-01

    An assessment of S-band communication equipment includes: (1) the review and analysis of the ability of the various subsystem avionic equipment designs to interface with, and operate on signals from/to adjoining equipment; (2) the performance peculiarities of the hardware against the overall specified system requirements; and (3) the evaluation of EMC EMI test results of the various equipment with respect to the possibility of mutual interferences.

  6. Design and Verification of a Distributed Communication Protocol

    NASA Technical Reports Server (NTRS)

    Munoz, Cesar A.; Goodloe, Alwyn E.

    2009-01-01

    The safety of remotely operated vehicles depends on the correctness of the distributed protocol that facilitates the communication between the vehicle and the operator. A failure in this communication can result in catastrophic loss of the vehicle. To complicate matters, the communication system may be required to satisfy several, possibly conflicting, requirements. The design of protocols is typically an informal process based on successive iterations of a prototype implementation. Yet distributed protocols are notoriously difficult to get correct using such informal techniques. We present a formal specification of the design of a distributed protocol intended for use in a remotely operated vehicle, which is built from the composition of several simpler protocols. We demonstrate proof strategies that allow us to prove properties of each component protocol individually while ensuring that the property is preserved in the composition forming the entire system. Given that designs are likely to evolve as additional requirements emerge, we show how we have automated most of the repetitive proof steps to enable verification of rapidly changing designs.

  7. Personal communication system combines high performance with miniaturization

    NASA Technical Reports Server (NTRS)

    Atlas, N. D.

    1967-01-01

    Personal communication system provides miniaturized components that incorporate high level signal characteristics plus noise rejection in both microphone and earphone circuitry. The microphone is designed to overcome such spacecraft flight problems as size, ambient noise level, and RF interference.

  8. ISS Update: High Rate Communications System

    NASA Video Gallery

    ISS Update Commentator Pat Ryan interviews Diego Serna, Communications and Tracking Officer, about the High Rate Communications System. Questions? Ask us on Twitter @NASA_Johnson and include the ha...

  9. Laser communication experiment. Volume 1: Design study report: Spacecraft transceiver. Part 1: Transceiver design

    NASA Technical Reports Server (NTRS)

    1970-01-01

    The ATS-F Laser Communications Experiment (LCE) is the first significant step in the application of laser systems to space communications. The space-qualified laser communications system being developed in this experiment, and the data resulting from its successful deployment in space, will be applicable to the use of laser communications systems in a wide variety of manned as well as unmanned space missions, both near earth and in deep space. Particular future NASA missions which can benefit from this effort are the Tracking and Data Relay Satellite System and the Earth Resources Satellites. The LCE makes use of carbon dioxide lasers to establish simultaneous, two-way communication between the ATS-F synchronous satellite and a ground station. In addition, the LCE is designed to permit communication with a similar spacecraft transceiver proposed to be flown on ATS-G, nominally one year after the launch of ATS-F. This would be the first attempt to employ lasers for satellite-to-satellite communications.

  10. Tunnel radio communications system at Stanford Linear Accelerator Center

    SciTech Connect

    Struven, W.C.

    1980-07-01

    A unique single frequency, dual daisy chain tunnel radio communication system has been developed for use in our new Positron-Electron Storage Ring. Communications are possible between portables in the underground ring and between a portable in the ring and all control rooms on the site. The system is designed as a wide band facility and therefore can carry many simplex and duplex transmissions. This system utilizes TV twinlead as a distributed antenna and repeater amplifiers to cover more than 7000 feet of underground tunnel. The design philosophy, tests and initial design are discussed and contrasted with the final implementation of the system. Future uses of the system are discussed.

  11. Sweat equity: a team approach to designing a new technology:customer-driven design of a picture archiving and communications systems (PACS) that works

    NASA Astrophysics Data System (ADS)

    Gelish, Anthony; Wright, Linda C.

    1994-05-01

    This paper defines the roles of customers and suppliers, customer variables, and customer contributions to the system creation process, discusses expected outcomes for a customer- driven system development process, and illustrates how this approach was used in the development of digital radiology.

  12. Vehicle-mounted real-time digital voice communication system based on visible light communication

    NASA Astrophysics Data System (ADS)

    Yan, Qiurong; Gu, Xiuxiu; Chen, Du; Wang, Hui; Huang, Hua; Chen, Xuxin; Cao, Qingshan; Liu, Hongqing

    2015-11-01

    Based on the phenomenon that more and more cars use LED for lighting and the current rise of visible light communication technology, this paper proposes a vehicle real-time voice communication system with high reliability on the basis of visible light communication for verification. The paper introduces the design of digital audio collection and output module, On-Off Keying (OOK) modulation and demodulation, Reed-Solomon encoding and decoding module, array LEDs emission and the module of PIN receiving signals. The LED lamp frequency response, communication distance, error rate and other parameters are tested and calibrated. The digital audio real-time communication system's receiving speed is 500Kbps when the communication distance is 3.9 meters.

  13. Smart Grid Communications System Blueprint

    NASA Astrophysics Data System (ADS)

    Clark, Adrian; Pavlovski, Chris

    2010-10-01

    Telecommunications operators are well versed in deploying 2G and 3G wireless networks. These networks presently support the mobile business user and/or retail consumer wishing to place conventional voice calls and data connections. The electrical power industry has recently commenced transformation of its distribution networks by deploying smart monitoring and control devices throughout their networks. This evolution of the network into a `smart grid' has also motivated the need to deploy wireless technologies that bridge the communication gap between the smart devices and information technology systems. The requirements of these networks differ from traditional wireless networks that communications operators have deployed, which have thus far forced energy companies to consider deploying their own wireless networks. We present our experience in deploying wireless networks to support the smart grid and highlight the key properties of these networks. These characteristics include application awareness, support for large numbers of simultaneous cell connections, high service coverage and prioritized routing of data. We also outline our target blueprint architecture that may be useful to the industry in building wireless and fixed networks to support the smart grid. By observing our experiences, telecommunications operators and equipment manufacturers will be able to augment their current networks and products in a way that accommodates the needs of the emerging industry of smart grids and intelligent electrical networks.

  14. Transition From NASA Space Communication Systems to Commerical Communication Products

    NASA Technical Reports Server (NTRS)

    Ghazvinian, Farzad; Lindsey, William C.

    1994-01-01

    Transitioning from twenty-five years of space communication system architecting, engineering and development to creating and marketing of commercial communication system hardware and software products is no simple task for small, high-tech system engineering companies whose major source of revenue has been the U.S. Government. Yet, many small businesses are faced with this onerous and perplexing task. The purpose of this talk/paper is to present one small business (LinCom) approach to taking advantage of the systems engineering expertise and knowledge captured in physical neural networks and simulation software by supporting numerous National Aeronautics and Space Administration (NASA) and the Department of Defense (DoD) projects, e.g., Space Shuttle, TDRSS, Space Station, DCSC, Milstar, etc. The innovative ingredients needed for a systems house to transition to a wireless communication system products house that supports personal communication services and networks (PCS and PCN) development in a global economy will be discussed. Efficient methods for using past government sponsored space system research and development to transition to VLSI communication chip set products will be presented along with notions of how synergy between government and industry can be maintained to benefit both parties.

  15. Wireless Augmented Reality Communication System

    NASA Technical Reports Server (NTRS)

    Devereaux, Ann (Inventor); Jedrey, Thomas (Inventor); Agan, Martin (Inventor)

    2015-01-01

    A portable unit is for video communication to select a user name in a user name network. A transceiver wirelessly accesses a communication network through a wireless connection to a general purpose node coupled to the communication network. A user interface can receive user input to log on to a user name network through the communication network. The user name network has a plurality of user names, at least one of the plurality of user names is associated with a remote portable unit, logged on to the user name network and available for video communication.

  16. Antenna design for the Inmarsat second generation communication satellites

    NASA Astrophysics Data System (ADS)

    Huang, C. C.; McDonach, C. A.

    1990-02-01

    The Inmarsat satellite system provides international marine communications. This paper presents the RF design of a family of three antennas giving global coverage for the second generation of Inmarsat spacecraft. The antennas are direct radiating arrays operating at L-band and C-band with circular polarization. A very stringent low profile requirement is achieved by the use of cup-dipole radiators and integrated feed technology. The design of the cup-dipole is presented in detail together with the trade-offs leading to its selection as the radiating element. The measured antenna performance for all three arrays is presented showing good agreement with theoretical predictions.

  17. Automatic communication signal monitoring system

    NASA Technical Reports Server (NTRS)

    Bernstein, A. J. (Inventor)

    1978-01-01

    A system is presented for automatic monitoring of a communication signal in the RF or IF spectrum utilizing a superheterodyne receiver technique with a VCO to select and sweep the frequency band of interest. A first memory is used to store one band sweep as a reference for continual comparison with subsequent band sweeps. Any deviation of a subsequent band sweep by more than a predetermined tolerance level produces an alarm signal which causes the band sweep data temporarily stored in one of two buffer memories to be transferred to long-term store while the other buffer memory is switched to its store mode to assume the task of temporarily storing subsequent band sweeps.

  18. Considerations for lunar colony communications systems

    NASA Technical Reports Server (NTRS)

    Dowling, Richard P.

    1992-01-01

    This paper addresses system aspects of communications for a lunar colony. Human factors are particularly noted. The practical aspects of communications infrastructure are emphasized rather than specific technologies. Communications needs for mission support and morale are discussed along with potential means of satisfying them. Problem areas are identified and some possible solutions are considered.

  19. Engineering multicellular systems by cell-cell communication

    PubMed Central

    Pai, Anand; Tanouchi, Yu; Collins, Cynthia; You, Lingchong

    2009-01-01

    Synthetic biology encompasses the design of new biological parts and systems as well as the modulation of existing biological networks to generate novel functions. In recent years, increasing emphasis has been placed on the engineering of population-level behaviors using cell-cell communication. From the engineering perspective, cell-cell communication serves as a versatile regulatory module that enables coordination among cells in and between populations and facilitates the generation of reliable dynamics. In addition to exploring biological “design principles” via the construction of increasingly complex dynamics, communication-based synthetic systems can be used as well-defined model systems to study ecological and social interactions such as competition, cooperation and predation. Here we discuss the dynamic properties of cell-cell communication modules, how they can be engineered for synthetic circuit design, and applications of these systems. PMID:19733047

  20. A new device for communication systems

    NASA Technical Reports Server (NTRS)

    Beck, R. R.

    1972-01-01

    A communication device and modulation capability were developed for the transmission of digital data or voices from point to point. This device is a fast-switching phase coherent frequency synthesizer. When this synthesizer is appropriately incorporated in a communication system it can provide interference resistance, multiple-user capability, user identification, ranging, navigation, Doppler correction, and digitized communication (voice and data). The application of this device to aircraft/airport complex and law enforcement communications is discussed.

  1. Experimental millimeter-wave satellite communications system

    NASA Astrophysics Data System (ADS)

    Shimada, Masaaaki; Suzuki, Yoshiaki; Arimoto, Yoshinori; Inoue, Akihiko; Kobayashi, Hideki; Okubo, Naofumi

    A 43/38 GHz (mm-wave) bands satellite communications experimental system featuring GEO/LEO and GEO/GEO intersatellite communications and personal communications is discussed in light of detailed performance data on the electrical model of the mm-wave transponder. Attention is given to the state-of-the-art solid-state power amplifiers, low-noise amplifiers, and personal communications terminal employed in these experiments.

  2. Design of a video teleconference facility for a synchronous satellite communications link

    NASA Technical Reports Server (NTRS)

    Richardson, M. D.

    1979-01-01

    The system requirements, design tradeoffs, and final design of a video teleconference facility are discussed, including proper lighting, graphics transmission, and picture aesthetics. Methods currently accepted in the television broadcast industry are used in the design. The unique problems associated with using an audio channel with a synchronous satellite communications link are discussed, and a final audio system design is presented.

  3. Software-defined Quantum Communication Systems

    SciTech Connect

    Humble, Travis S; Sadlier, Ronald J

    2013-01-01

    We show how to extend the paradigm of software-defined communication to include quantum communication systems. We introduce the decomposition of a quantum communication terminal into layers separating the concerns of the hardware, software, and middleware. We provide detailed descriptions of how each component operates and we include results of an implementation of the super-dense coding protocol. We argue that the versatility of software-defined quantum communication test beds can be useful for exploring new regimes in communication and rapidly prototyping new systems.

  4. Communication in Performance-Based Training and Instruction: From Design to Practice

    ERIC Educational Resources Information Center

    Larbi-Apau, Josephine A.; Moseley, James L.

    2009-01-01

    Communication is inextricably important to instructional design and performance-based training. Promoting effective communication as an integral part of the performance support system improves professional instructional design functions and offers greater avenues for meaningful discourse among end users of the instruction. In this article, we…

  5. 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.

  6. Flexible satellite communications systems simulator standard device groups

    NASA Astrophysics Data System (ADS)

    Brown, D. W.; Burgess, J. L.

    1986-12-01

    This document contains the designs of the standard device groups (SDG) prepared for the Flexible Satellite Communications Systems Simulation (FSCSS). It contains updates to SDGs prepared for earlier versions of FSCSS and new SDG's prepared for version 4.0. FSCSS is a time domain simulation for accurately determining performance of satellite communications system principally in terms of bit error rate. SDGs are models of earth terminals, satellites and modems from the inventory of the Deense Satellite Communications System (DSCS). These ready-made SATCOM components ease the burden of a FSCSS user setting up large DSCS Systems within FSCSS.

  7. Business Process Flow Diagrams in Tissue Bank Informatics System Design, and Identification and Communication of Best Practices: The Pharmaceutical Industry Experience.

    PubMed

    McDonald, Sandra A; Velasco, Elizabeth; Ilasi, Nicholas T

    2010-12-01

    Pfizer, Inc.'s Tissue Bank, in conjunction with Pfizer's BioBank (biofluid repository), endeavored to create an overarching internal software package to cover all general functions of both research facilities, including sample receipt, reconciliation, processing, storage, and ordering. Business process flow diagrams were developed by the Tissue Bank and Informatics teams as a way of characterizing best practices both within the Bank and in its interactions with key internal and external stakeholders. Besides serving as a first step for the software development, such formalized process maps greatly assisted the identification and communication of best practices and the optimization of current procedures. The diagrams shared here could assist other biospecimen research repositories (both pharmaceutical and other settings) for comparative purposes or as a guide to successful informatics design. Therefore, it is recommended that biorepositories consider establishing formalized business process flow diagrams for their laboratories, to address these objectives of communication and strategy. PMID:23386924

  8. How do communication systems emerge?

    PubMed Central

    Scott-Phillips, Thomas C.; Blythe, Richard A.; Gardner, Andy; West, Stuart A.

    2012-01-01

    Communication involves a pair of behaviours—a signal and a response—that are functionally interdependent. Consequently, the emergence of communication involves a chicken-and-egg problem: if signals and responses are dependent on one another, then how does such a relationship emerge in the first place? The empirical literature suggests two solutions to this problem: ritualization and sensory manipulation; and instances of ritualization appear to be more common. However, it is not clear from a theoretical perspective why this should be the case, nor if there are any other routes to communication. Here, we develop an analytical model to examine how communication can emerge. We show that: (i) a state of non-interaction is evolutionarily stable, and so communication will not necessarily emerge even when it is in both parties' interest; (ii) the conditions for sensory manipulation are more stringent than for ritualization, and hence ritualization is likely to be more common; and (iii) communication can arise by a third route, when the intention to communicate can itself be communicated, but this may be limited to humans. More generally, our results demonstrate the utility of a functional approach to communication. PMID:22217724

  9. Satellite communications

    NASA Astrophysics Data System (ADS)

    Saha, M. K.

    1982-11-01

    The paper describes the basic principles and the historial development of satellite communications. Various satellite systems for global communications are discused and compared. Some typical operational communication satellite systems summary including geostationary systems are presented. Considerations leading to the system design including the link design for various multiple access techniques and the future trends in satellite communications systems are also discussed.

  10. Research on space communication equipment technology: Study on relay system

    NASA Astrophysics Data System (ADS)

    1992-08-01

    An overview of the research on space communication equipment technology, especially relay technology, are presented. Low Noise Amplifier (LNA) design review was conducted and the temporal tendency of the noise factors are shown. Design study on Solid State Power Amplifier (SSPA), characterized in small size, low weight, low deformation, and high reliability, was conducted and SSPA development tendency is shown. The results of the review on advanced communication systems are summarized.

  11. A Study of Synchronization Techniques for Optical Communication Systems

    NASA Technical Reports Server (NTRS)

    Gagliardi, R. M.

    1975-01-01

    The study of synchronization techniques and related topics in the design of high data rate, deep space, optical communication systems was reported. Data cover: (1) effects of timing errors in narrow pulsed digital optical systems, (2) accuracy of microwave timing systems operating in low powered optical systems, (3) development of improved tracking systems for the optical channel and determination of their tracking performance, (4) development of usable photodetector mathematical models for application to analysis and performance design in communication receivers, and (5) study application of multi-level block encoding to optical transmission of digital data.

  12. Employee Communication: Designing and Managing a People-Sensitive Process of Internal Communication.

    ERIC Educational Resources Information Center

    D'Aprix, Roger

    1987-01-01

    Schools have concentrated on school-community communication in public relations programs and have tended to shortchange school-employee communication systems. Discusses research on employee communication systems (the grapevine is a primary source) and the implications the findings delineate. For employees to function with commitment,…

  13. Optical Design of an Optical Communications Terminal

    NASA Technical Reports Server (NTRS)

    Biswas, Abhijit; Page, Norman; Hemmati, Hamid

    2005-01-01

    An optical communications terminal (OCT) is being developed to enable transmission of data at a rate as high as 2.5 Gb/s, from an aircraft or spacecraft to a ground station. In addition to transmitting high data rates, OCT will also be capable of bidirectional communications.

  14. Visual Communication in Web Design - Analyzing Visual Communication in Web Design

    NASA Astrophysics Data System (ADS)

    Thorlacius, Lisbeth

    Web sites are rapidly becoming the preferred media choice for information search, company presentation, shopping, entertainment, education, and social contacts. And along with the various forms of communication that the Web offers the aesthetic aspects have begun to play an increasingly important role. However, studies in the design and the relevance of focusing on the aesthetic aspects in planning and using Web sites have only to a smaller degree been subject of theoretical reflection. For example, Miller (2000), Thorlacius (2001, 2002, 2005), Engholm (2002, 2003), and Beaird (2007) have been contributing to set a beginning agenda that address the aesthetic aspects. On the other hand, there is a considerable amount of literature addressing the theoretical and methodological aspects focusing on the technical and functional aspects. In this context it is the aim of this article to introduce a model for analysis of visual communication on websites.

  15. Random digital encryption secure communication system

    NASA Technical Reports Server (NTRS)

    Doland, G. D. (Inventor)

    1982-01-01

    The design of a secure communication system is described. A product code, formed from two pseudorandom sequences of digital bits, is used to encipher or scramble data prior to transmission. The two pseudorandom sequences are periodically changed at intervals before they have had time to repeat. One of the two sequences is transmitted continuously with the scrambled data for synchronization. In the receiver portion of the system, the incoming signal is compared with one of two locally generated pseudorandom sequences until correspondence between the sequences is obtained. At this time, the two locally generated sequences are formed into a product code which deciphers the data from the incoming signal. Provision is made to ensure synchronization of the transmitting and receiving portions of the system.

  16. Overview of the Preliminary Design of the Optical Communication Demonstration and High-Rate Link Facility

    NASA Technical Reports Server (NTRS)

    Sandusky, John V.; Jeganathan, M.; Ortiz, G.; Biswas, A.; Lee, S.; Parker, G.; Liu, B.; Johnson, D.; DePew, J.; Lesh, J. R.

    2000-01-01

    Tlis paper presents an overview of the preliminary design of both the flight and ground systems of the Optical Communication Demonstration and High-Rate Link Facility which will demonstrate optical communication from the International Space Station to ground after its deployment in October 2002. The overview of the preliminary design of the Flight System proceeds by contrasting it with the design of the laboratory-model unit, emphasizing key changes and the rationale behind the design choices. After presenting the preliminary design of the Ground System, the timetable for the construction and deployment of the flight and ground systems is outlined.

  17. Glenn Research Center quantum communicator receiver design and development

    NASA Astrophysics Data System (ADS)

    Hizlan, Murad; Lekki, John D.; Nguyen, Binh V.

    2009-10-01

    We investigate, design, and develop a prototype real-time synchronous receiver for the second-generation quantum communicator recently developed at the National Aeronautics and Space Administration (NASA) Glenn Research Center. This communication system exploits the temporal coincidences between simultaneously fired low-power laser sources to communicate at power levels several orders of magnitude less than what is currently achievable through classical means, with the ultimate goal of creating ultra-low-power microsize optical communications and sensing devices. The proposed receiver uses a unique adaptation of the early-late gate method for symbol synchronization and a newly identified 31-bit synchronization word for frame synchronization. This receiver, implemented in a field-programmable gate array (FPGA), also provides a number of significant additional features over the existing non-real-time experimental receiver, such as real-time bit error rate (BER) statistics collection and display, and recovery and display of embedded textual information. It also exhibits an indefinite run time and statistics collection.

  18. Systems and Methods for Radar Data Communication

    NASA Technical Reports Server (NTRS)

    Bunch, Brian (Inventor); Szeto, Roland (Inventor); Miller, Brad (Inventor)

    2013-01-01

    A radar information processing system is operable to process high bandwidth radar information received from a radar system into low bandwidth radar information that may be communicated to a low bandwidth connection coupled to an electronic flight bag (EFB). An exemplary embodiment receives radar information from a radar system, the radar information communicated from the radar system at a first bandwidth; processes the received radar information into processed radar information, the processed radar information configured for communication over a connection operable at a second bandwidth, the second bandwidth lower than the first bandwidth; and communicates the radar information from a radar system, the radar information communicated from the radar system at a first bandwidth.

  19. Technology Evaluation of Programmable Communicating Thermostats with Radio Broadcast Data System Communications

    SciTech Connect

    Herter, Karen; Wayland, Seth

    2008-10-31

    Programmable Communicating Thermostats are thermostats that can be programmed by the user to respond to signals indicating a grid-level system emergency or pricing event. The California Energy Commission is considering standards that would include a requirement for Programmable Communicating Thermostats in residential and small commercial applications. The current specification for Programmable Communicating Thermostats requires Radio Data System communications to Programmable Communicating Thermostats. This study tested the signal strength and reliability of Radio Data System signals at 40 customer sites within the Sacramento Municipal Utility District, which is serviced by 17 radio stations that already transmit Radio Data System signals. The study also tested the functionality of a commercially available Programmable Communicating Thermostat for compliance with California Energy Commission design standards. Test results demonstrated that Radio Data System is capable of reliably sending price and emergency signals. This study also provides evidence that existing Programmable Communicating Thermostats, on receiving a Radio Data System pricing or event signal, are capable of automatically increasing set points to a customer-determined or utility-determined level, thus providing air-conditioning demand response within seconds or just a few (less than 5) minutes.

  20. Augmentative Communication: Assessment, System Selection, and Usage.

    ERIC Educational Resources Information Center

    DeRuyter, Frank; Becker, Mary R.

    1988-01-01

    Augmentative communication systems for the nonspeaking brain-injured should be carefully selected to serve a variety of functions. These include the utilization of systems for communication purposes, assessment of cognitive-linguistic deficits, integration and participation by the individual in the rehabilitation program, and improvement in an…

  1. Organization of Communication in Information Systems.

    ERIC Educational Resources Information Center

    Datsenko, V. P.; Zaytsev, N. G.

    Organization of communication between the center of an automated system of information exchange and the subscribers to the system is described. The three requirements are: (1) those technical communication means must be chosen which will provide effective and convenient avenues for calls from the subscribers to the center, (2) the required…

  2. 33 CFR 127.111 - Communications systems.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 33 Navigation and Navigable Waters 2 2012-07-01 2012-07-01 false Communications systems. 127.111 Section 127.111 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED... Waterfront Facilities Handling Liquefied Natural Gas § 127.111 Communications systems. (a) The...

  3. 33 CFR 127.111 - Communications systems.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 33 Navigation and Navigable Waters 2 2014-07-01 2014-07-01 false Communications systems. 127.111 Section 127.111 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED... Waterfront Facilities Handling Liquefied Natural Gas § 127.111 Communications systems. (a) The...

  4. 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...

  5. 46 CFR 130.440 - Communications system.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 46 Shipping 4 2012-10-01 2012-10-01 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...

  6. 46 CFR 130.440 - Communications system.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 46 Shipping 4 2014-10-01 2014-10-01 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...

  7. 46 CFR 130.440 - Communications system.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 46 Shipping 4 2011-10-01 2011-10-01 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...

  8. 46 CFR 130.440 - Communications system.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 46 Shipping 4 2013-10-01 2013-10-01 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...

  9. Recipient design in human communication: simple heuristics or perspective taking?

    PubMed Central

    Blokpoel, Mark; van Kesteren, Marlieke; Stolk, Arjen; Haselager, Pim; Toni, Ivan; van Rooij, Iris

    2012-01-01

    Humans have a remarkable capacity for tuning their communicative behaviors to different addressees, a phenomenon also known as recipient design. It remains unclear how this tuning of communicative behavior is implemented during live human interactions. Classical theories of communication postulate that recipient design involves perspective taking, i.e., the communicator selects her behavior based on her hypotheses about beliefs and knowledge of the recipient. More recently, researchers have argued that perspective taking is computationally too costly to be a plausible mechanism in everyday human communication. These researchers propose that computationally simple mechanisms, or heuristics, are exploited to perform recipient design. Such heuristics may be able to adapt communicative behavior to an addressee with no consideration for the addressee's beliefs and knowledge. To test whether the simpler of the two mechanisms is sufficient for explaining the “how” of recipient design we studied communicators' behaviors in the context of a non-verbal communicative task (the Tacit Communication Game, TCG). We found that the specificity of the observed trial-by-trial adjustments made by communicators is parsimoniously explained by perspective taking, but not by simple heuristics. This finding is important as it suggests that humans do have a computationally efficient way of taking beliefs and knowledge of a recipient into account. PMID:23055960

  10. Electro-Optical Design for Efficient Visual Communication

    NASA Technical Reports Server (NTRS)

    Huck, Friedrich O.; Fales, Carl L.; Jobson, Daniel J.; Rahman, Zia-Ur

    1995-01-01

    Visual communication, in the form of telephotography and television, for example, can be regarded as efficient only if the amount of information that it conveys about the scene to the observer approaches the maximum possible and the associated cost approaches the minimum possible. Elsewhere we have addressed the problem of assessing the end to end performance of visual communication systems in terms of their efficiency in this sense by integrating the critical limiting factors that constrain image gathering into classical communications theory. We use this approach to assess the electro-optical design of image gathering devices as a function of the f number and apodization of the objective lens and the aperture size and sampling geometry of the phot-detection mechanism. Results show that an image gathering device that is designed to optimize information capacity performs similarly to the human eye. For both, the performance approaches the maximum possible, in terms of the efficiency with which the acquired information can be transmitted as decorrelated data, and the fidelity, sharpness, and clearity with which fine detail can be restored.

  11. Software Design Analyzer System

    NASA Technical Reports Server (NTRS)

    Tausworthe, R. C.

    1985-01-01

    CRISP80 software design analyzer system a set of programs that supports top-down, hierarchic, modular structured design, and programing methodologies. CRISP80 allows for expression of design as picture of program.

  12. Performance of a communication satellite system in simulated RFI

    NASA Technical Reports Server (NTRS)

    Riddle, L. P.

    1981-01-01

    Vulnerability of an advanced communication satellite system to pulsed RFI is examined. Results of an experimental simulation are compared with calculated system degradation. System performance in pulsed RFI is found to be quite good with well-designed ground receiving equipment.

  13. Automated testing of developmental satellite communications systems and subsystems

    NASA Technical Reports Server (NTRS)

    Shalkhauser, K. A.; Kerczewski, R. J.

    1985-01-01

    Lower frequency bands allocated for satellite communications use are becoming saturated due to steadily increasing demand. An ongoing program to develop the new technologies required to meet the demands of future systems is described. Higher frequency components and more efficient system techniques are developed. In order to accurately evaluate the performance of these technologies, an automated test system was designed and built. The automated system's design an capabilities are discussed.

  14. 622 Mbps High-speed satellite communication system for WINDS

    NASA Astrophysics Data System (ADS)

    Ogawa, Yasuo; Hashimoto, Yukio; Yoshimura, Naoko; Suzuki, Ryutaro; Gedney, Richard T.; Dollard, Mike

    2006-07-01

    WINDS is the experimental communications satellite currently under joint development by Japanese Aerospace Exploration Agency (JAXA) and the National Institute of Information and Communications Technology (NICT). The high-speed satellite communication system is very effective for quick deployment of high-speed networks economically. The WINDS will realize ultra high-speed networking and demonstrate operability of satellite communication systems in high-speed internet. NICT is now developing high-speed satellite communication system for WINDS. High-speed TDMA burst modem with high performance TPC error correction is underdevelopment. Up to the DAC on the transmitter and from the ADC on the receiver, all modem functions are performed in the digital processing technology. Burst modem has been designed for a user data rate up to 1244 Mbps. NICT is developing the digital terminal as a user interface and a network controller for this earth station. High compatibility with the Internet will be provided.

  15. VLSI system design

    NASA Astrophysics Data System (ADS)

    Muroga, S.

    A complete picture of LSI/VLSI system design is provided, encompassing both engineering and economic considerations. The subjects discussed include: cost analysis based on production volume, yield, chip size, design manpower and other factors; bipolar and MOS logic families, logic design procedures, and mask designs; use of ROMs and PLAs in logic design, along with design algorithms; a survey of CAD used in LSI/VLSI chip design. Also covered are: full-custom and semicustom designs; microprocessor and dedicated processor chips; system design and hardware-software tradeoffs; LSI/VLSI technological trends; new products realized by LSI/VLSI technology; future production and management problems.

  16. ETS-VI multibeam satellite communications systems

    NASA Astrophysics Data System (ADS)

    Kawai, Makoto; Tanaka, Masayoshi; Ohtomo, Isao

    1989-10-01

    The fixed and mobile satellite communications systems of the Japanese Engineering Test Satellite-VI (ETS-VI) are described. The system requirements are outlined along with the system configuration. The ETS-VI multibeam system employs three frequency bands. When used for Ka-band fixed communications, it covers the Japanese main islands with thirteen 0.3-degree-wide spot beam. Four of the beams are active for ETS-VI. When used for S-band mobile communications, five beams cover the area within 200 nautical miles from the Japanese coast. The C-band beam for fixed communications covers the central area of the Japanese main islands with a single beam. The onboard antenna system is described along with the transponders and their associated onboard systems. A discussion of the system technology follows, covering the TDMA transmisssion system, the relay function, rainfall compensation, and the antenna and propagation performance.

  17. Scenarios, personas and user stories from design ethnography: Evidence-based design representations of communicable disease investigations

    PubMed Central

    Turner, Anne M; Reeder, Blaine; Ramey, Judith

    2014-01-01

    Purpose Despite years of effort and millions of dollars spent to create a unified electronic communicable disease reporting systems, the goal remains elusive. A major barrier has been a lack of understanding by system designers of communicable disease (CD) work and the public health workers who perform this work. This study reports on the application of User Center Design representations, traditionally used for improving interface design, to translate the complex CD work identified through ethnographic studies to guide designers and developers of CD systems. The purpose of this work is to: (1) better understand public health practitioners and their information workflow with respect to communicable disease (CD) monitoring and control at a local health department, and (2) to develop evidence-based design representations that model this CD work to inform the design of future disease surveillance systems. Methods We performed extensive onsite semi-structured interviews, targeted work shadowing and a focus group to characterize local health department communicable disease workflow. Informed by principles of design ethnography and user-centered design (UCD) we created persona, scenarios and user stories to accurately represent the user to system designers. Results We sought to convey to designers the key findings from ethnographic studies: 1) that public health CD work is mobile and episodic, in contrast to current CD reporting systems, which are stationary and fixed 2) health department efforts are focused on CD investigation and response rather than reporting and 3) current CD information systems must conform to PH workflow to ensure their usefulness. In an effort to illustrate our findings to designers, we developed three contemporary design-support representations: persona, scenario, and user story. Conclusions Through application of user centered design principles, we were able to create design representations that illustrate complex public health communicable

  18. Energy Systems Design

    NASA Technical Reports Server (NTRS)

    1986-01-01

    PRESTO, a COSMIC program, handles energy system specifications and predicts design efficiency of cogeneration systems. These systems allow a company to use excess energy produced to generate electricity. PRESTO is utilized by the Energy Systems Division of Thermo Electron Corporation in the custom design of cogeneration systems.

  19. Roadside-based communication system and method

    NASA Technical Reports Server (NTRS)

    Bachelder, Aaron D. (Inventor)

    2007-01-01

    A roadside-based communication system providing backup communication between emergency mobile units and emergency command centers. In the event of failure of a primary communication, the mobile units transmit wireless messages to nearby roadside controllers that may take the form of intersection controllers. The intersection controllers receive the wireless messages, convert the messages into standard digital streams, and transmit the digital streams along a citywide network to a destination intersection or command center.

  20. Advanced integrated WDM system for POF communication

    NASA Astrophysics Data System (ADS)

    Haupt, M.; Fischer, U. H. P.

    2009-01-01

    Polymer Optical Fibres (POFs) show clear advantages compared to copper and glass fibres. In essence, POFs are inexpensive, space-saving and not susceptible to electromagnetic interference. Thus, the usage of POFs have become a reasonable alternative in short distance data communication. Today, POFs are applied in a wide number of applications due to these specific advantages. These applications include automotive communication systems and in-house-networks. State-of-the-art is to transmit data with only one channel over POF, this limits the bandwidth. To solve this problem, an integrated MUX/DEMUX-element for WDM over POF is designed and developed to use multiple channels. This integration leads to low costs, therefore this component is suitable for mass market applications. The fundamental idea is to separate the chromatic parts of the light in its monochromatic components by means of a grating based on an aspheric mirror. Due to the high NA of the POF the setup has to be designed in a 3D-approach. Therefore this setup cannot be compared with the planar solutions available on market, they would result high losses in the 3rd dimension. To achieve a fast and optimized design an optical simulation program is used. Particular attention has to be paid to the design of the POF as a light source in the simulation program and the optimisation of the grating. The following realization of the demultiplexer is planed to be done with injection molding. This technology offers easy and very economical processing. These advantages make this technology first choice for optical components in the low-cost array.

  1. Topology design and performance analysis of an integrated communication network

    NASA Technical Reports Server (NTRS)

    Li, V. O. K.; Lam, Y. F.; Hou, T. C.; Yuen, J. H.

    1985-01-01

    A research study on the topology design and performance analysis for the Space Station Information System (SSIS) network is conducted. It is begun with a survey of existing research efforts in network topology design. Then a new approach for topology design is presented. It uses an efficient algorithm to generate candidate network designs (consisting of subsets of the set of all network components) in increasing order of their total costs, and checks each design to see if it forms an acceptable network. This technique gives the true cost-optimal network, and is particularly useful when the network has many constraints and not too many components. The algorithm for generating subsets is described in detail, and various aspects of the overall design procedure are discussed. Two more efficient versions of this algorithm (applicable in specific situations) are also given. Next, two important aspects of network performance analysis: network reliability and message delays are discussed. A new model is introduced to study the reliability of a network with dependent failures. For message delays, a collection of formulas from existing research results is given to compute or estimate the delays of messages in a communication network without making the independence assumption. The design algorithm coded in PASCAL is included as an appendix.

  2. Control system design guide

    SciTech Connect

    Sellers, David; Friedman, Hannah; Haasl, Tudi; Bourassa, Norman; Piette, Mary Ann

    2003-05-01

    The ''Control System Design Guide'' (Design Guide) provides methods and recommendations for the control system design process and control point selection and installation. Control systems are often the most problematic system in a building. A good design process that takes into account maintenance, operation, and commissioning can lead to a smoothly operating and efficient building. To this end, the Design Guide provides a toolbox of templates for improving control system design and specification. HVAC designers are the primary audience for the Design Guide. The control design process it presents will help produce well-designed control systems that achieve efficient and robust operation. The spreadsheet examples for control valve schedules, damper schedules, and points lists can streamline the use of the control system design concepts set forth in the Design Guide by providing convenient starting points from which designers can build. Although each reader brings their own unique questions to the text, the Design Guide contains information that designers, commissioning providers, operators, and owners will find useful.

  3. The design of space optical communications terminal with high efficient

    NASA Astrophysics Data System (ADS)

    Deng, Xiaoguo; Li, Gang; Jiang, Bo; Yang, Xiaoxu; Yan, Peipei

    2015-02-01

    In order to improve high-speed laser space optical communications terminal receive energy and emission energy, meet the demand of mini-type and light-type for space-based bear platform, based on multiple-reflect coaxial optical receiving antenna structure, while considering the installation difficulty, a high-efficient optical system had been designed, which aperture is off-axial, both signal-receiving sub-optical system and emission sub-optical system share a same primary optical path. By the separating light lens behind the primary optical path, the received light with little energy will be filtered and shaped and then transmitted to each detector, at the same time, by the coupling element, the high-power laser will be coupling into optical antenna, and then emitted to outside. Applied the power-detected optical system evaluate principle, the optimized off-axial optical system's efficiency had been compared with the coaxial optical system. While, analyzed the Gauss beam energy distribution by numerical theory, discussed that whether off-axis optical system can be an emission terminal, verify the feasibility of the theory of the design of the system.

  4. 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.

  5. Strategic Choices for Data Communications Systems.

    ERIC Educational Resources Information Center

    Arns, Robert G.; Urban, Patricia A.

    Issues and strategies for developing a campus data communications system are discussed. It is suggested that individual microcomputer (MC) workstations will occasionally have a need for (1) access, via a data communications network, to a more powerful processor; (2) specialized software; (3) sophisticated output devices; (4) central data sets; or…

  6. How to Bootstrap a Human Communication System

    ERIC Educational Resources Information Center

    Fay, Nicolas; Arbib, Michael; Garrod, Simon

    2013-01-01

    How might a human communication system be bootstrapped in the absence of conventional language? We argue that motivated signs play an important role (i.e., signs that are linked to meaning by structural resemblance or by natural association). An experimental study is then reported in which participants try to communicate a range of pre-specified…

  7. Gas Main Sensor and Communications Network System

    SciTech Connect

    Hagen Schempf

    2006-05-31

    Automatika, Inc. was contracted by the Department of Energy (DOE) and with co-funding from the Northeast Gas Association (NGA), to develop an in-pipe natural gas prototype measurement and wireless communications system for assessing and monitoring distribution networks. This projected was completed in April 2006, and culminated in the installation of more than 2 dozen GasNet nodes in both low- and high-pressure cast-iron and steel mains owned by multiple utilities in the northeastern US. Utilities are currently logging data (off-line) and monitoring data in real time from single and multiple networked sensors over cellular networks and collecting data using wireless bluetooth PDA systems. The system was designed to be modular, using in-pipe sensor-wands capable of measuring, flow, pressure, temperature, water-content and vibration. Internal antennae allowed for the use of the pipe-internals as a waveguide for setting up a sensor network to collect data from multiple nodes simultaneously. Sensor nodes were designed to be installed with low- and no-blow techniques and tools. Using a multi-drop bus technique with a custom protocol, all electronics were designed to be buriable and allow for on-board data-collection (SD-card), wireless relaying and cellular network forwarding. Installation options afforded by the design included direct-burial and external polemounted variants. Power was provided by one or more batteries, direct AC-power (Class I Div.2) and solar-array. The utilities are currently in a data-collection phase and intend to use the collected (and processed) data to make capital improvement decisions, compare it to Stoner model predictions and evaluate the use of such a system for future expansion, technology-improvement and commercialization starting later in 2006.

  8. Simulation and communication analysis of the monitoring system for hydraulic support pressure based on CAN bus

    NASA Astrophysics Data System (ADS)

    Jin, Huawei; Luo, Ming; Zhang, Xin; Wang, Wei

    2016-01-01

    In order to realize online real-time monitoring of the hydraulic bracket support, improve the existing communication system, and improve the reliability of data transmission, this paper set up the communication simulation system and platform to simulate the coal mine communication based CAN bus. Based on the design and analysis of system hardware and software, this paper completed the construction of the whole hardware and the debugging of communication system. The debug end can communicate simulate by the CAN protocol simulation device, and realized the work of the entire communication system. Experiments showed that the monitoring system can work reliably.

  9. Augmentation of a commercial satellite system for military communications

    NASA Astrophysics Data System (ADS)

    Butte, Eric G.; Thorburn, Michael

    2005-06-01

    Future U.S. MILSATCOM will rely on a complex satellite design to implement the TSAT satellite system that was developed on the Transformational Communication Architecture program. TSAT will deliver secured IP based, on-demand communication system to meet the needs of the military and the warfighter and will demand a very large satellite system, program, and an anticipated lengthy deployment time. An alternate system is proposed that can give IP based communications in a significantly shorter time frame. A constellation of commercial-like satellites, with transponded Ka-, Ku- and X-band, would nicely complement the MILSATCOM fleet. The services provided by these satellites would enable widespread communications services such as IP to the theatre, augmenting the DSCS, Wideband Gapfiller, and protected communications systems of MILSTAR and Advanced EHF. The capacity provided by the dedicated commercial satellites would help provide the capacity demanded by the warfighter as MILSATCOM transitions from today's technology to the TSAT system of tomorrow's Transformational Communications Architecture. This paper will discuss the satellite concept design and how it can augment the MILSATCOM fleet and show a more flexible approach of bandwidth management to support fixed and COTM terminals.

  10. Communication Support System in Emergency Considering Dynamic Connection of Organization

    NASA Astrophysics Data System (ADS)

    Morimoto, Yasumasa; Nakatani, Mie; Nishida, Shogo

    It is frequently observed in emergent situation that important information does not reach to an right person or department in the organization because of the confusion after the emergency or in some case because of lack of knowledge on contact address. This phenomenon happens especially when different organizations are connected dynamically in emergency and it is very important to support communication in emergent situations. This paper deals with a communication support system considering dynamic organizational connection in emergency. The system is based on the communication model that considers human related factors such as “competence", “duty", “responsibility" and “knowledge" in organization. On the basis of the model, a communication support system to give contact address depending on the situation is designed and a prototype system with GUI is developed.

  11. Assessment of Communication Competencies in Engineering Design Projects.

    ERIC Educational Resources Information Center

    Brinkman, Gert W.; van der Geest, Thea M.

    2003-01-01

    Notes that reforms in engineering education have caused a shift from the traditional stand-alone courses in technical communication for engineering students towards communication training integrated in courses and design projects that allows students to develop four levels of competence. Describes three formats for integrated communication…

  12. Designing the Group Use Videodisc: Socializing Communication Technology.

    ERIC Educational Resources Information Center

    Acker, Stephen R.; Gordon, Joan M.

    Designed to examine the relevance of television news programming, a study examined the application of a "group use" videodisc in a communication curriculum. Using a computer controlled videodisc, 60 communication students at a large midwestern university were shown the agenda-setting function of television and asked to evaluate the experience.…

  13. A figure of merit for competing communications satellite designs

    NASA Technical Reports Server (NTRS)

    Lovell, R. R.; Fordyce, S. W.

    1983-01-01

    Trends in launch schedules, weights, power, and space segment costs per transponder year for Intelsats and North American domsats (domestic communications satellites) are discussed. The Intelsat system currently services 25,000 point to point telephone links at any one moment, and a $3 billion order has been placed for Intelsat VIs, which feature 36,000 telephone circuits each. The Intelsat VI spacecraft will weigh 1670 kg in orbit, a continuance of the trend to heavier satellites, while the domsats will stay at 650 kg due to launch vehicle limitations. Direct television broadcast satellites are being designed for receive only (R/O) earth stations, with each satellite capable of servicing 50,000 individual ground stations. Competition is growing for C and Ku band satellite transponders for DBS, with costs $350,000 each. No standardized design has yet emerged.

  14. 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

  15. Design Languages: A Powerful Medium for Communicating Designs.

    ERIC Educational Resources Information Center

    Seo, Kay Kyeongju; Gibbons, Andrew S.

    2003-01-01

    Defines design languages as collections of terms that can be used as the primitive words for expressing design sentences. Explains the use of design languages in an instructional design context, including identifying design language terms, design language flexibility, and sharing design languages for cooperative dialogs. (Author/LRW)

  16. Office Design: The Spatial Dimension of Organizational Communication and Reflector of Communication Climate.

    ERIC Educational Resources Information Center

    Schmidt, Wallace V.; Dorsey, Mary Elizabeth

    In addition to serving as executive enclosures, offices illustrate organizational goals and reflect the communication climate of the organization. Traditional office designs accentuate personal territory, in which communication is largely controlled by the occupant of the office, and space often becomes a symbol of status. One of the first major…

  17. 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

  18. Shuttle orbiter S-band payload communications equipment design evaluation

    NASA Technical Reports Server (NTRS)

    Springett, J. C.; Maronde, R. G.

    1979-01-01

    The analysis of the design, and the performance assessment of the Orbiter S-band communication equipment are reported. The equipment considered include: network transponder, network signal processor, FM transmitter, FM signal processor, payload interrogator, and payload signal processor.

  19. Satellite multiple access systems for mobile communication

    NASA Technical Reports Server (NTRS)

    Lewis, J. L.

    1979-01-01

    This paper considers multiple access techniques for a mobile radio system which incorporates a geosynchronous orbiting satellite repeater through which mobile terminals communicate. The communication capacities of FDMA, TDMA and CDMA systems are examined for a 4 MHz bandwidth system to serve up to 10,000 users. An FDMA system with multibeam coverage is analyzed in detail. The system includes an order-wire network for demand-access control and reassignment of satellite channels. Satellite and terminal configurations are developed to a block diagram level and system costs and implementation requirements are discussed.

  20. 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.

  1. An all digital low data rate communication system

    NASA Technical Reports Server (NTRS)

    Chen, C.; Fan, M.

    1973-01-01

    The advent of digital hardwares has made it feasible to implement many communication system components digitally. With the exception of frequency down conversion, the proposed low data rate communication system uses digital hardwares completely. Although the system is designed primarily for deep space communications with large frequency uncertainty and low signal-to-noise ratio, it is also suitable for other low data rate applications with time-shared operation among a number of channels. Emphasis is placed on the fast Fourier transform receiver and the automatic frequency control via digital filtering. The speed available from the digital system allows sophisticated signal processing to reduce frequency uncertainty and to increase the signal-to-noise ratio. The practical limitations of the system such as the finite register length are examined. It is concluded that the proposed all-digital system is not only technically feasible but also has potential cost reduction over the existing receiving systems.

  2. Systems Theory and Communication. Annotated Bibliography.

    ERIC Educational Resources Information Center

    Covington, William G., Jr.

    This annotated bibliography presents annotations of 31 books and journal articles dealing with systems theory and its relation to organizational communication, marketing, information theory, and cybernetics. Materials were published between 1963 and 1992 and are listed alphabetically by author. (RS)

  3. Nutrition Implementation Programs as Communication Systems

    ERIC Educational Resources Information Center

    Fugelsang, Andreas

    1972-01-01

    Description of a model nutrition implementation program as a communication system. Focus is on developing countries where, author maintains, there is an over-emphasis on surveys and collection of data. Problems on program implementation are discussed. (LK)

  4. ATCOM: Automatically Tuned Collective Communication System for SMP Clusters

    SciTech Connect

    Meng-Shiou Wu

    2005-12-17

    Conventional implementations of collective communications are based on point-to-point communications, and their optimizations have been focused on efficiency of those communication algorithms. However, point-to-point communications are not the optimal choice for modern computing clusters of SMPs due to their two-level communication structure. In recent years, a few research efforts have investigated efficient collective communications for SMP clusters. This dissertation is focused on platform-independent algorithms and implementations in this area. There are two main approaches to implementing efficient collective communications for clusters of SMPs: using shared memory operations for intra-node communications, and overlapping inter-node/intra-node communications. The former fully utilizes the hardware based shared memory of an SMP, and the latter takes advantage of the inherent hierarchy of the communications within a cluster of SMPs. Previous studies focused on clusters of SMP from certain vendors. However, the previously proposed methods are not portable to other systems. Because the performance optimization issue is very complicated and the developing process is very time consuming, it is highly desired to have self-tuning, platform-independent implementations. As proven in this dissertation, such an implementation can significantly out-perform the other point-to-point based portable implementations and some platform-specific implementations. The dissertation describes in detail the architecture of the platform-independent implementation. There are four system components: shared memory-based collective communications, overlapping mechanisms for inter-node and intra-node communications, a prediction-based tuning module and a micro-benchmark based tuning module. Each component is carefully designed with the goal of automatic tuning in mind.

  5. Market Related System Analysis of Satellite Communication Networks

    NASA Astrophysics Data System (ADS)

    Malyshev, V. V.; Panasenkova, M. V.

    2002-01-01

    The report is devoted to the technique of effectiveness analysis of communication space system with satellites in geostationary orbit using market models. The technique is worked out in order to choose the most optimal alternative of communication space system design. The alternative considered optimal and the system effective when the maximum profit from the system with limited system costs is achieved. The key point of the technique is a wide use of market models and application of market related parameters as an integral part of the design technique in order to secure the high commercial output of the communication space system. A range of models for decisive characteristics of communication space system is synthesized in terms of the technique. Flexible market model with detailed insight into the structure of the given market sector and its trends is created. The technique enables to choose the image and key parameters of the future system such as payload and ground sector characteristics so as to make the system most cost-effective and profitable. It is shown that such factors as the choice of launch vehicle can influence the system effectiveness rather dramatically. In particular, it is shown that under certain conditions delivering the small (five hundred kg) satellite to the geostationary orbit with the help of light-weight launch vehicle and the satellite's own electro-rocket thrusters is forty per cent more cost- effective than when the satellite is delivered with the help of the medium-size launch vehicle. The latter case can lead to the significant losses due to high launch costs that are nearly two times higher for the medium size launch vehicle than for the light launce vehicle. The technique is applicable both for designing a wide range of communication space systems and is recommended for those dealing with designing commercial systems. It can also be used to update and improve the systems that are already in operation.

  6. NLOS UV communication for distributed sensor systems

    NASA Astrophysics Data System (ADS)

    Shaw, Gary A.; Nischan, Melissa L.; Iyengar, Mrinal A.; Kaushik, Sumanth; Griffin, Michael K.

    2000-11-01

    Atmospheric scattering of ultraviolet light is examined as a mechanism for short-range, non-line-of-sight (NLOS) communication between nodes in energy-constrained distributed sensor networks. The physics of scattering is discussed and modeled, and progress in the development of solid state sources and detectors is briefly summarized. The performance of a representative NLOS UV communication system is analyzed by means of a simulation model and compared to conventional RF systems in terms of covertness and transceiver power. A test bed for evaluating NLOS UV communication hardware and modulation schemes is described.

  7. Effects of picture exchange communication system on communication and behavioral anomalies in autism.

    PubMed

    Malhotra, Shahzadi; Rajender, Gaurav; Bhatia, Manjeet S; Singh, Tej B

    2010-07-01

    Communication skills deficits and stereotyped behaviors are frequently found among people with pervasive developmental disabilities like autism. These communication and behavioral oddities of autism are often considered to be difficult to treat and are challenging. Picture exchange communication system (PECS) is a six-phase picture system based on applied behavior analysis and is specially designed to overcome these communication difficulties in children with autism by encouraging the child to be the communication initiator. The present paper throws light on the process of using PECS along with other traditional behavioral approaches in managing communication deficits and behavioral stereotypies in a seven-year-old male child diagnosed as having childhood autism. The identified target behaviors of repeated head turning, flapping his hands, poor communication skills were assessed using various rating scales including visual analogue scale as per clinician observation and parental reports and managed using PECS as an adjunct to traditional behavioral techniques of contingency management, differential reinforcement, task direction and reprimand. Outcome was assessed using same tools after thirty-two sessions of interventions spread over three months. Significant improvements of around 60% were observed in the target behaviors. PMID:21716776

  8. Data communications

    SciTech Connect

    Preckshot, G.G.

    1993-08-01

    The purpose of this paper is to recommend regulatory guidance for reviewers examining computer communication systems used in nuclear power plants. The recommendations cover three areas important to these communications systems: system design, communication protocols, and communication media. The first area, system design, considers three aspects of system design--questions about architecture, specific risky design elements or omissions to look for in designs being reviewed, and recommendations for multiplexed data communication systems used in safety systems. The second area reviews pertinent aspects of communication protocol design and makes recommendations for newly designed protocols or the selection of existing protocols for safety system, information display, and non-safety control system use. The third area covers communication media selection, which differs significantly from traditional wire and cable. The recommendations for communication media extend or enhance the concerns of published IEEE standards about three subjects: data rate, imported hazards and maintainability.

  9. Satellite communication subsystem design for the Indonesian Archipelago

    NASA Astrophysics Data System (ADS)

    Gaspari, R. A.; Neuman, M. E.; Asturi, H.

    To meet the requirements of the Indonesian Archipelago, an advanced communication subsystem was designed which incorporated many key system advances. Orthogonally polarized grid reflectors, offset feed with displaced foci, provide shaped beam coverage of orthogonal polarizations with maximum reflector area for each. The 24 channels of 36 MHz each are implemented by functionally separate horizontal and vertical repeaters. High efficiency traveling wave tubes with triply depressed collectors provide downlink power amplification, while a 5 for 4 redundancy implementation insures reliability. Channel selectivity is established by elliptic function input and output multiplexers utilizing circulator dropping techniques on the input and common manifold combining on the output. As a result of this system implementation, it has been possible to achieve 34 dBW downlink EIRP and -5 dB K uplink G/T with a much smaller spacecraft than previously achieved.

  10. DOE Integrated Security System (DISS) preliminary communication security analysis

    SciTech Connect

    Sweeney, D.J.

    1993-10-01

    The purpose of this analysis is to document a technical approach to improve DOE Integrated Security System (DISS) dial-up communications security and the requirements to address them. This document is not intended as a comprehensive analysis of the security aspects of the DISS computer system but rather as an analysis of the dial-up communications security as it pertains to the use of the DISS database in the new DOE Automated Visitors Access Control System (DAVACS) procedures. Current access controls into the DISS will be discussed with emphasis on the DAVACS procedures. Recommendations will be provided for increasing the dial-up communications security into DISS as it relates to the automated visit procedures. Finally a design for an encrypted dial-up communication link to DISS will be given.

  11. Design Requirements for Communication-Intensive Interactive Applications

    NASA Astrophysics Data System (ADS)

    Bolchini, Davide; Garzotto, Franca; Paolini, Paolo

    Online interactive applications call for new requirements paradigms to capture the growing complexity of computer-mediated communication. Crafting successful interactive applications (such as websites and multimedia) involves modeling the requirements for the user experience, including those leading to content design, usable information architecture and interaction, in profound coordination with the communication goals of all stakeholders involved, ranging from persuasion to social engagement, to call for action. To face this grand challenge, we propose a methodology for modeling communication requirements and provide a set of operational conceptual tools to be used in complex projects with multiple stakeholders. Through examples from real-life projects and lessons-learned from direct experience, we draw on the concepts of brand, value, communication goals, information and persuasion requirements to systematically guide analysts to master the multifaceted connections of these elements as drivers to inform successful communication designs.

  12. ASIC Design and Data Communications for the Boston Retinal Prosthesis

    PubMed Central

    Shire, Douglas B.; Ellersick, William; Kelly, Shawn K.; Doyle, Patrick; Priplata, Attila; Drohan, William; Mendoza, Oscar; Gingerich, Marcus; McKee, Bruce; Wyatt, John L.; Rizzo, Joseph F.

    2016-01-01

    We report on the design and testing of a custom application-specific integrated circuit (ASIC) that has been developed as a key component of the Boston retinal prosthesis. This device has been designed for patients who are blind due to age-related macular degeneration or retinitis pigmentosa. Key safety and communication features of the low-power ASIC are described, as are the highly configurable neural stimulation current waveforms that are delivered to its greater than 256 output electrodes. The ASIC was created using an 0.18 micron Si fabrication process utilizing standard 1.8 volt CMOS transistors as well as 20 volt lightly doped drain FETs. The communication system receives frequency-shift keyed inputs at 6.78 MHz from an implanted secondary coil, and transmits data back to the control unit through a lower-bandwidth channel that employs load-shift keying. The design’s safety is ensured by on-board electrode voltage monitoring, stimulus charge limits, error checking of data transmitted to the implant, and comprehensive self-test and performance monitoring features. Each stimulus cycle is initiated by a transmitted word with a full 32-bit error check code. Taken together, these features allow researchers to safely and wirelessly tailor retinal stimulation and vision recovery for each patient. PMID:23365888

  13. Tags, wireless communication systems, tag communication methods, and wireless communications methods

    DOEpatents

    Scott; Jeff W. , Pratt; Richard M.

    2006-09-12

    Tags, wireless communication systems, tag communication methods, and wireless communications methods are described. In one aspect, a tag includes a plurality of antennas configured to receive a plurality of first wireless communication signals comprising data from a reader, a plurality of rectifying circuits coupled with. respective individual ones of the antennas and configured to provide rectified signals corresponding to the first wireless communication signals, wherein the rectified signals are combined to produce a composite signal, an adaptive reference circuit configured to vary a reference signal responsive to the composite signal, a comparator coupled with the adaptive reference circuit and the rectifying circuits and configured to compare the composite signal with respect to the reference signal and to output the data responsive to the comparison, and processing circuitry configured to receive the data from the comparator and to process the data.

  14. Designing Better Preschools: Improving Communication between Designers and Child Development Professionals

    ERIC Educational Resources Information Center

    Beacham, Cindy V.

    2006-01-01

    This exploratory study examined communications between designers and child development professionals during the preschool design process. Qualitative interviews and focus groups were conducted to investigate the need for communication support between child development professionals, parents, and design professionals (n = 20) during the process of…

  15. The potential of dyslexic individuals in communication design education.

    PubMed

    Corlu, Muzaffer; Ozcan, Oğuzhan; Korkmazlar, Umran

    2007-01-01

    If dyslexic individuals have the ability to express themselves in different ways, particularly in the field of modern graphic design, would they be a favoured group in creating the extraordinary and outstanding ideas that are required in communication design? The study group consisted of 20 primary school dyslexics between ages of 7-12 and 20 non-dyslexics serving as a control group. A jury with four specialists evaluated the drawings gathered from the 40 participants. Even though we might not say surely that the dyslexics are the best possible candidates for communication design education, based on the statistical results we have concluded that they should be among the potential candidates for both general communication design education and for more specific minor study areas such as icon design. PMID:18430979

  16. Designing Simulation Systems

    ERIC Educational Resources Information Center

    Twelker, Paul A.

    1969-01-01

    "The purpose of this paper is to outline the approach to designing instructional simulation systems developed at Teaching Research. The 13 phases of simulation design will be summarized, and an effort will be made to expose the vital decision points that confront the designer as he develops simulation experiences. (Author)

  17. The Effectiveness of the "Picture Exchange Communication System" with Nonspeaking Adults

    ERIC Educational Resources Information Center

    Stoner, Julia B.; Beck, Ann R.; Bock, Stacey Jones; Hickey, Katherine; Kosuwan, Kullaya; Thompson, James R.

    2006-01-01

    "Picture Exchange Communication System" (PECS) training was implemented with 5 nonspeaking adults with mental retardation who were not currently using any type of functional communication system. A modified ABAB, single-subject design was used to assess the effectiveness of PECS in enhancing the functional communication skills of these…

  18. Full-duplex optical communication system

    NASA Technical Reports Server (NTRS)

    Shay, Thomas M. (Inventor); Hazzard, David A. (Inventor); Horan, Stephen (Inventor); Payne, Jason A. (Inventor)

    2004-01-01

    A method of full-duplex electromagnetic communication wherein a pair of data modulation formats are selected for the forward and return data links respectively such that the forward data electro-magnetic beam serves as a carrier for the return data. A method of encoding optical information is used wherein right-hand and left-hand circular polarizations are assigned to optical information to represent binary states. An application for an earth to low earth orbit optical communications system is presented which implements the full-duplex communication and circular polarization keying modulation format.

  19. 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.

  20. Parametric analysis of RF communications and tracking systems for manned space stations

    NASA Technical Reports Server (NTRS)

    1972-01-01

    System performance, system interface compatibility, and system management and operations are analyzed for external and internal communications provided by the modular space station. Mathematical models are utilized to evaluate performances of the various communication links between the MSS and the tracking and data relay satellites, the shuttle, and the ground stations. Communication control design requirements are determined from overall MSS control design and checkout requirements are developed in a related systems study. Parallel design efforts consider equipment configurations for the external communication assembly baseband and the internal communication assembly to accommodate signal transfer and control. The recommended baseline design considers also interfaces between equipment groups and the critical functional and signal characteristics of these interfaces. The data processing assembly has direct communication circuits to the external communication assembly and the control interface is provided via a digital data bus and a remote acquisition and control unit.

  1. Laser Communication Demonstration System (LCDS) and future mobile satellite services

    NASA Technical Reports Server (NTRS)

    Chen, Chien-Chung; Wilhelm, Michael D.; Lesh, James R.

    1995-01-01

    The Laser Communications Demonstration System (LCDS) is a proposed in-orbit demonstration of high data rate laser communications technology conceived jointly by NASA and U.S. industry. The program objectives are to stimulate industry development and to demonstrate the readiness of high data rate optical communications in Earth orbit. For future global satellite communication systems using intersatellite links, laser communications technology can offer reduced mass and power requirements and higher channel bandwidths without regulatory constraints. As currently envisioned, LCDS will consist of one or two orbiting laser communications terminals capable of demonstrating high data rate (greater than 750Mbps) transmission in a dynamic space environment. Two study teams led by Motorola and Ball Aerospace are currently in the process of conducting a Phase A/B mission definition study of LCDS under contracts with JPL/NASA. The studies consist of future application survey, concept and requirements definition, and a point design of the laser communications flight demonstration. It is planned that a single demonstration system will be developed based on the study results. The Phase A/B study is expected to be completed by the coming June, and the current results of the study are presented in this paper.

  2. System 80+ D-RAP, a communication tool

    SciTech Connect

    Siegmann, E.R.; Mody, A.A.

    1994-12-31

    The purpose of {open_quotes}RAP{close_quotes} music is to communicate, and the purpose of D-RAP is to foster communication between the probabilistic risk assessment (PRA) group, designers, and the future combined operating license (COL) applicant. This is to ensure that the design is self-consistent and integrated with the procurement process. The designer reliability assurance program (D-RAP) is the first part of the RAP. The goals of the D-RAP are to have risk-significant systems, structures, and components (SSCs) identified and considered in the detail design and procurement phases and to maintain consistency between PRA and design. Plant safety is maintained throughout the design phase, and pertinent information is passed on to the COL applicant. The operations RAP (O-RAP) covers the plant operation and maintenance.

  3. A native IP satellite communications system

    NASA Astrophysics Data System (ADS)

    Koudelka, O.; Schmidt, M.; Ebert, J.; Schlemmer, H.; Kastner-Puschl, S.; Riedler, W.

    2004-08-01

    ≪ In the framework of ESA's ARTES-5 program the Institute of Applied Systems Technology (Joanneum Research) in cooperation with the Department of Communications and Wave Propagation has developed a novel meshed satellite communications system which is optimised for Internet traffic and applications (L*IP—Local Network Interconnection via Satellite Systems Using the IP Protocol Suite). Both symmetrical and asymmetrical connections are supported. Bandwidth on demand and guaranteed quality of service are key features of the system. A novel multi-frequency TDMA access scheme utilises efficient methods of IP encapsulation. In contrast to other solutions it avoids legacy transport network techniques. While the DVB-RCS standard is based on ATM or MPEG transport cells, the solution of the L*IP system uses variable-length cells which reduces the overhead significantly. A flexible and programmable platform based on Linux machines was chosen to allow the easy implementation and adaptation to different standards. This offers the possibility to apply the system not only to satellite communications, but provides seamless integration with terrestrial fixed broadcast wireless access systems. The platform is also an ideal test-bed for a variety of interactive broadband communications systems. The paper describes the system architecture and the key features of the system.

  4. Reactive system verification case study: Fault-tolerant transputer communication

    NASA Technical Reports Server (NTRS)

    Crane, D. Francis; Hamory, Philip J.

    1993-01-01

    A reactive program is one which engages in an ongoing interaction with its environment. A system which is controlled by an embedded reactive program is called a reactive system. Examples of reactive systems are aircraft flight management systems, bank automatic teller machine (ATM) networks, airline reservation systems, and computer operating systems. Reactive systems are often naturally modeled (for logical design purposes) as a composition of autonomous processes which progress concurrently and which communicate to share information and/or to coordinate activities. Formal (i.e., mathematical) frameworks for system verification are tools used to increase the users' confidence that a system design satisfies its specification. A framework for reactive system verification includes formal languages for system modeling and for behavior specification and decision procedures and/or proof-systems for verifying that the system model satisfies the system specifications. Using the Ostroff framework for reactive system verification, an approach to achieving fault-tolerant communication between transputers was shown to be effective. The key components of the design, the decoupler processes, may be viewed as discrete-event-controllers introduced to constrain system behavior such that system specifications are satisfied. The Ostroff framework was also effective. The expressiveness of the modeling language permitted construction of a faithful model of the transputer network. The relevant specifications were readily expressed in the specification language. The set of decision procedures provided was adequate to verify the specifications of interest. The need for improved support for system behavior visualization is emphasized.

  5. S-band antenna phased array communications system

    NASA Technical Reports Server (NTRS)

    Delzer, D. R.; Chapman, J. E.; Griffin, R. A.

    1975-01-01

    The development of an S-band antenna phased array for spacecraft to spacecraft communication is discussed. The system requirements, antenna array subsystem design, and hardware implementation are examined. It is stated that the phased array approach offers the greatest simplicity and lowest cost. The objectives of the development contract are defined as: (1) design of a medium gain active phased array S-band communications antenna, (2) development and test of a model of a seven element planar array of radiating elements mounted in the appropriate cavity matrix, and (3) development and test of a breadboard transmit/receive microelectronics module.

  6. Application and design of solar photovoltaic system

    NASA Astrophysics Data System (ADS)

    Tianze, Li; Hengwei, Lu; Chuan, Jiang; Luan, Hou; Xia, Zhang

    2011-02-01

    Solar modules, power electronic equipments which include the charge-discharge controller, the inverter, the test instrumentation and the computer monitoring, and the storage battery or the other energy storage and auxiliary generating plant make up of the photovoltaic system which is shown in the thesis. PV system design should follow to meet the load supply requirements, make system low cost, seriously consider the design of software and hardware, and make general software design prior to hardware design in the paper. To take the design of PV system for an example, the paper gives the analysis of the design of system software and system hardware, economic benefit, and basic ideas and steps of the installation and the connection of the system. It elaborates on the information acquisition, the software and hardware design of the system, the evaluation and optimization of the system. Finally, it shows the analysis and prospect of the application of photovoltaic technology in outer space, solar lamps, freeways and communications.

  7. Tri-band microstrip antenna design for wireless communication applications

    NASA Astrophysics Data System (ADS)

    Sami, Gehan; Mohanna, Mahmoud; Rabeh, Mohamed L.

    2013-06-01

    This paper introduces a novel rectangular tri-band patch antenna that is fabricated and measured for wireless communication systems. The introduced antenna is designed for WLAN and WiMAX applications. The desired tri-band operation was obtained by proper loading for a rectangular patch antenna using slots and shorting pins. The optimal location and dimension for the loaded elements were obtained with the aid of interfacing a Genetic Algorithm (GA) model with an Ansoft High Frequency Structural Simulator (HFSS). The results obtained from our simulated antenna show 5.8% impedance matching band width at 2.4 GHz, 3.7% at 3.5 GHz and 1.57% at 5.7 GHz. In addition, an equivalent circuit of the proposed antenna is introduced using the least square curve fitting optimization technique.

  8. Communicating Qualitative Research Study Designs to Research Ethics Review Boards

    ERIC Educational Resources Information Center

    Ells, Carolyn

    2011-01-01

    Researchers using qualitative methodologies appear to be particularly prone to having their study designs called into question by research ethics or funding agency review committees. In this paper, the author considers the issue of communicating qualitative research study designs in the context of institutional research ethics review and offers…

  9. A Comprehensive Learning Event Design Using a Communication Framework

    ERIC Educational Resources Information Center

    Bower, Robert L.

    1975-01-01

    A learning event design for accountability uses a communications framework. The example given is a slide presentation on the invasion of Cuba during the Spanish-American War. Design components include introduction, objectives, media, involvement plans, motivation, bibliography, recapitulation, involvement sheets, evaluation, stimulus-response…

  10. Communication Resource Use in a Networked Collaborative Design Environment.

    ERIC Educational Resources Information Center

    Gay, Geri; Lentini, Marc

    The purpose of this exploratory study was to examine student use of a prototype networked collaborative design environment to support or augment learning about engineering design. The theoretical framework is based primarily on Vygotsky's social construction of knowledge and the belief that collaboration and communication are critical components…

  11. Communication Design Education: Could Nine Reflections Be Sufficient?

    ERIC Educational Resources Information Center

    van der Waarde, Karel; Vroombout, Maurits

    2012-01-01

    Situation: Graphic design education is subject to substantial changes. Changes in professional practice and higher education aggravate insecurities about the contents and structure of courses, assessment criteria, relations between practice, research and theory and teaching methods. Assumption: Graphic design education (visual communication design…

  12. Principles and Concepts for Information and Communication Technology Design.

    ERIC Educational Resources Information Center

    Adams, Ray; Langdon, Patrick

    2003-01-01

    This article presents a theory for evaluating information and communication technology design for individuals with disabilities. Simplex 1 evaluates designs in five zones: sensory and input zone; output zone; abstract working memory; long-term memory; and central executive functioning. Simplex 2 evaluates feedback, emotional responses, cognitive…

  13. Role of Communication Networks in Behavioral Systems Analysis

    ERIC Educational Resources Information Center

    Houmanfar, Ramona; Rodrigues, Nischal Joseph; Smith, Gregory S.

    2009-01-01

    This article provides an overview of communication networks and the role of verbal behavior in behavioral systems analysis. Our discussion highlights styles of leadership in the design and implementation of effective organizational contingencies that affect ways by which coordinated work practices are managed. We draw upon literature pertaining to…

  14. Underwater Wireless Optical Communication System Using Blue LEDs

    NASA Astrophysics Data System (ADS)

    Lin, Aobo; Tong, Zheng; Song, Yuhang; Kong, Meiwei; Xu, Jing

    2016-02-01

    We demonstrate a self-designed underwater wireless optical communication system using blue LEDs. The performance of the transmitter and receiver was experimentally investigated. Four different square wave signals (10 KHz, 100 KHz, 500 KHz and 1 MHz) were successfully transmitted via a short water channel at the first phase.

  15. Communication Systems Simulator with Error Correcting Codes Using MATLAB

    ERIC Educational Resources Information Center

    Gomez, C.; Gonzalez, J. E.; Pardo, J. M.

    2003-01-01

    In this work, the characteristics of a simulator for channel coding techniques used in communication systems, are described. This software has been designed for engineering students in order to facilitate the understanding of how the error correcting codes work. To help students understand easily the concepts related to these kinds of codes, a…

  16. A Prototype HTML Training System for Graphic Communication Majors

    ERIC Educational Resources Information Center

    Runquist, Roger L.

    2010-01-01

    This design research demonstrates a prototype content management system capable of training graphic communication students in the creation of basic HTML web pages. The prototype serve as a method of helping students learn basic HTML structure and commands earlier in their academic careers. Exposure to the concepts of web page creation early in…

  17. Training Paraprofessionals to Implement the Picture Exchange Communication System (PECS)

    ERIC Educational Resources Information Center

    Sloman, Glenn Matthew

    2010-01-01

    Based on Skinner's "Verbal Behavior" (1957), the picture exchange communication system (PECS) was designed to teach children with autism functional verbal behavior. Much research has demonstrated the effectiveness and efficiency of PECS in building verbal behavior. However, because PECS training is typically presented in a group format and later…

  18. Effects of Implementing the Picture Exchange Communication System (PECS) with Adults with Developmental Disabilities and Severe Communication Deficits

    ERIC Educational Resources Information Center

    Conklin, Carl G.; Mayer, G. Roy

    2011-01-01

    The purpose of this study is to evaluate the effects of "Picture Exchange Communication System" (PECS) training, using a multiple baseline design on the independent initiations of three adults with developmental disabilities and severe communication deficits. All participants increased their independent initiations, although at different levels of…

  19. Communicating Physics and the Design of Textbooks.

    ERIC Educational Resources Information Center

    Barojas, Jorge; Trigueros, Maria

    1991-01-01

    The planning of an introductory calculus textbook in classical mechanics is shown as an example of an approach to textbook design that uses four main cognitive categories: sources of learning, instruments of learning, processes of knowing, and mechanisms of knowing. The aspects, domains, description, and elements of each section of the textbook…

  20. Pacs: Part Of An Integrated Communications System

    NASA Astrophysics Data System (ADS)

    Thompson, B. G.; Brenton, Bradley C.; Staab, Edward V.; Perry, J. Randolph; Parrish, Denise; Johnston, R. Eugene; Creasy, Jeffrey L.

    1985-09-01

    The Department of Radiology at the University of North Carolina-Chapel Hill (UNC) has developed the concept for an integrated picture archiving and communications system. A communications network has been installed, and computer facilities are being interfaced within radiology areas. Other projects include the establishment of a computer simulation model of departmental operations and assembly of a limited picture archival and communication system (PACS) beginning with the CT and NMR Modalities. While this approach may provide immediate clinical benefits, the initial thrust has been towards evaluation of prototype systems with flexibility for modifications. PACS operational parameters are being studied for their acceptability in support of radiology clinical services. The goal is to provide objective operational data as a basis for planning system improvements.

  1. Architectural Design for a Mars Communications and Navigation Orbital Infrastructure

    NASA Technical Reports Server (NTRS)

    Ceasrone R. J.; Hastrup, R. C.; Bell, D. J.; Roncoli, R. B.; Nelson, K.

    1999-01-01

    The planet Mars has become the focus of an intensive series of missions that span decades of time, a wide array of international agencies and an evolution from robotics to humans. The number of missions to Mars at any one time, and over a period of time, is unprecedented in the annals of space exploration. To meet the operational needs of this exploratory fleet will require the implementation of new architectural concepts for communications and navigation. To this end, NASA's Jet Propulsion Laboratory has begun to define and develop a Mars communications and navigation orbital infrastructure. This architecture will make extensive use of assets at Mars, as well as use of traditional Earth-based assets, such as the Deep Space Network, DSN. Indeed, the total system can be thought of as an extension of DSN nodes and services to the Mars in-situ region. The concept has been likened to the beginnings of an interplanetary Internet that will bring the exploration of Mars right into our living rooms. The paper will begin with a high-level overview of the concept for the Mars communications and navigation infrastructure. Next, the mission requirements will be presented. These will include the relatively near-term needs of robotic landers, rovers, ascent vehicles, balloons, airplanes, and possibly orbiting, arriving and departing spacecraft. Requirements envisioned for the human exploration of Mars will also be described. The important Mars orbit design trades on telecommunications and navigation capabilities will be summarized, and the baseline infrastructure will be described. A roadmap of NASA's plan to evolve this infrastructure over time will be shown. Finally, launch considerations and delivery to Mars will be briefly treated.

  2. Influence: The Organizer in Communication Systems

    ERIC Educational Resources Information Center

    Browning, Larry; And Others

    1976-01-01

    This paper outlines an array of categories that denote kinds of influence variables operative in organizational systems--including structures, relationships, and technology. This allows us to synthesize literature from a variety of system levels and sources by addressing the question: What variables influence a communicator's behavior at any given…

  3. School Planning, Evaluation and Communication System (SPECS).

    ERIC Educational Resources Information Center

    Flocco, Edward C.

    A comprehensive school planning tool is available from General Learning Corporation and the Center for the Advanced Study of Educational Administration at the University of Oregon. This School Planning, Evaluation and Communication System (SPECS) provides a deliverable system of training, implementation strategies and materials and technical…

  4. Name Authority Control in a Communication System.

    ERIC Educational Resources Information Center

    Elias, Cathy Ann; Fair, C. James

    1983-01-01

    Examines use of Electronic Office System by Corporate Media Relations, a division of Communication Services, Standard Oil Company, focusing on the problem of name authority control. The media query file, variant entry problems, problems resulting from ineffective name authority control, and developing a control system are covered. Four sources are…

  5. A Systemic Perspective of Communication and Sexism.

    ERIC Educational Resources Information Center

    Drecksel, Debra

    Communication and sexism are analyzed from a systemic perspective, illustrating how sexism is perpetuated through sexist interaction and symbol systems. Sexism is shown to be a disease in our society, which creates a societal situation with double-binding sex-role symbols which limit our adaptability. A remedy for sexism is suggested which…

  6. Communications satellite systems operations with the space station, volume 2

    NASA Technical Reports Server (NTRS)

    Price, K.; Dixon, J.; Weyandt, C.

    1987-01-01

    A financial model was developed which described quantitatively the economics of the space segment of communication satellite systems. The model describes the economics of the space system throughout the lifetime of the satellite. The expected state-of-the-art status of communications satellite systems and operations beginning service in 1995 were assessed and described. New or enhanced space-based activities and associated satellite system designs that have the potential to achieve future communications satellite operations in geostationary orbit with improved economic performance were postulated and defined. Three scenarios using combinations of space-based activities were analyzed: a spin stabilized satellite, a three axis satellite, and assembly at the Space Station and GEO servicing. Functional and technical requirements placed on the Space Station by the scenarios were detailed. Requirements on the satellite were also listed.

  7. An all digital low data rate communication system

    NASA Technical Reports Server (NTRS)

    Chen, C.-H.; Fan, M.

    1973-01-01

    The advent of digital hardwares has made it feasible to implement many communication system components digitally. With the exception of frequency down conversion, the proposed low data rate communication system uses digital hardware completely. Although the system is designed primarily for deep space communications with large frequency uncertainty and low signal-to-noise ratio, it is also suitable for other low data rate applications with time-shared operation among a number of channels. Emphasis is placed on the fast Fourier transform receiver and the automatic frequency control via digital filtering. The speed available from the digital system allows sophisticated signal processing to reduce frequency uncertainty and to increase the signal-to-noise ratio.

  8. High speed laser communication network for satellite systems

    NASA Astrophysics Data System (ADS)

    Panahi, Allen; Kazemi, Alex A.

    2011-06-01

    Using optical links in space and building high speed laser communications network has proven to be an extremely complicated task and many such schemes were tried without success in the past. However, in the last few years, there has been impressive progress made to bring the concept to fruition in civilian and government-non classified projects. In this paper we will focus on the requirements of the space-based lasers and optics used for beam forming, as well as receiver antenna gain and detectors used in free space communications. High data rate, small antenna size, narrow beam divergence, and a narrow field of view are characteristics of laser communications that offer a number of potential advantages for system design. Space-based optical communications using satellites in low earth orbit (LEO) and Geo-synchronous orbits (GEO) hold great promise for the proposed Internet in the Sky network of the future. Also discussed are the critical parameters in the transmitter, channel, receiver, and link budget that are employed in successful inter-satellite communications system. We cover that Laser Communications offer a viable alternative to established RF communications for inter-satellite links and other applications where high performance links are a necessity.

  9. Hydrological Monitoring System Design and Implementation Based on IOT

    NASA Astrophysics Data System (ADS)

    Han, Kun; Zhang, Dacheng; Bo, Jingyi; Zhang, Zhiguang

    In this article, an embedded system development platform based on GSM communication is proposed. Through its application in hydrology monitoring management, the author makes discussion about communication reliability and lightning protection, suggests detail solutions, and also analyzes design and realization of upper computer software. Finally, communication program is given. Hydrology monitoring system from wireless communication network is a typical practical application of embedded system, which has realized intelligence, modernization, high-efficiency and networking of hydrology monitoring management.

  10. Fast massive preventive security and information communication systems

    NASA Astrophysics Data System (ADS)

    Akopian, David; Chen, Philip; Miryakar, Susheel; Kumar, Abhinav

    2008-04-01

    We present a fast massive information communication system for data collection from distributive sources such as cell phone users. As a very important application one can mention preventive notification systems when timely notification and evidence communication may help to improve safety and security through wide public involvement by ensuring easy-to-access and easy-to-communicate information systems. The technology significantly simplifies the response to the events and will help e.g. special agencies to gather crucial information in time and respond as quickly as possible. Cellular phones are nowadays affordable for most of the residents and became a common personal accessory. The paper describes several ways to design such systems including existing internet access capabilities of cell phones or downloadable specialized software. We provide examples of such designs. The main idea is in structuring information in predetermined way and communicating data through a centralized gate-server which will automatically process information and forward it to a proper destination. The gate-server eliminates a need in knowing contact data and specific local community infrastructure. All the cell phones will have self-localizing capability according to FCC E911 mandate, thus the communicated information can be further tagged automatically by location and time information.

  11. Communication Simulations for Power System Applications

    SciTech Connect

    Fuller, Jason C.; Ciraci, Selim; Daily, Jeffrey A.; Fisher, Andrew R.; Hauer, Matthew L.

    2013-05-29

    New smart grid technologies and concepts, such as dynamic pricing, demand response, dynamic state estimation, and wide area monitoring, protection, and control, are expected to require considerable communication resources. As the cost of retrofit can be high, future power grids will require the integration of high-speed, secure connections with legacy communication systems, while still providing adequate system control and security. While considerable work has been performed to create co-simulators for the power domain with load models and market operations, limited work has been performed in integrating communications directly into a power domain solver. The simulation of communication and power systems will become more important as the two systems become more inter-related. This paper will discuss ongoing work at Pacific Northwest National Laboratory to create a flexible, high-speed power and communication system co-simulator for smart grid applications. The framework for the software will be described, including architecture considerations for modular, high performance computing and large-scale scalability (serialization, load balancing, partitioning, cross-platform support, etc.). The current simulator supports the ns-3 (telecommunications) and GridLAB-D (distribution systems) simulators. Ongoing and future work will be described, including planned future expansions for a traditional transmission solver. A test case using the co-simulator, utilizing a transactive demand response system created for the Olympic Peninsula and AEP gridSMART demonstrations, requiring two-way communication between distributed and centralized market devices, will be used to demonstrate the value and intended purpose of the co-simulation environment.

  12. RDS-SL VS Communication System

    Energy Science and Technology Software Center (ESTSC)

    2012-09-12

    The RDS-SL VS Communication System is a component of the Radiation Detection System for Strategic, Low-Volume Seaports. Its purpose is to acquire real-time data from radiation portal monitors and cameras, record that data in a database, and make it available to system operators and administrators via a web interface. The software system contains two components: a standalone data acquisition and storage component and an ASP.NETweb application that implements the web interface.

  13. Residential photovoltaic system designs

    SciTech Connect

    Russell, M. C.

    1981-01-01

    A project to develop Residential Photovoltaic Systems has begun at Massachusetts Institute of Technology Lincoln Laboratory with the construction and testing of five Prototype Systems. All of these systems utilize a roof-mounted photovoltaic array and allow excess solar-generated electric energy to be fed back to the local utility grid, eliminating the need for on-site storage. Residential photovoltaic system design issues are discussed and specific features of the five Prototype Systems now under test are presented.

  14. Control system design method

    DOEpatents

    Wilson, David G.; Robinett, III, Rush D.

    2012-02-21

    A control system design method and concomitant control system comprising representing a physical apparatus to be controlled as a Hamiltonian system, determining elements of the Hamiltonian system representation which are power generators, power dissipators, and power storage devices, analyzing stability and performance of the Hamiltonian system based on the results of the determining step and determining necessary and sufficient conditions for stability of the Hamiltonian system, creating a stable control system based on the results of the analyzing step, and employing the resulting control system to control the physical apparatus.

  15. Secure optical communication system utilizing deformable MEMS mirrors

    NASA Astrophysics Data System (ADS)

    Ziph-Schatzberg, Leah; Bifano, Thomas; Cornelissen, Steven; Stewart, Jason; Bleier, Zvi

    2009-02-01

    An optical communication system suitable for voice, data retrieval from remote sensors and identification is described. The system design allows operation at ranges of several hundred meters. The heart of the system is a modulated MEMS mirror that is electrostatically actuated and changes between a flat reflective state and a corrugated diffractive state. A process for mass producing these mirrors at low cost was developed and is described. The mirror was incorporated as a facet in a hollow retro-reflector, allowing temporal modulation of an interrogating beam and the return of the modulated beam to the interrogator. This system thus consists of a low power, small and light communication node with large (about 60°) angular extent. The system's range and pointing are determined by the interrogator /detector/demodulator (Transceiver) unit. The transceiver is comprised of an optical channel to establish line of sight communication, an interrogating laser at 1550nm, an avalanche photo diode to detect the return signal and electronics to drive the laser and demodulate the detected signal and convert it to an audio signal. A functional prototype system was built using a modified compact optical sight as the transceiver. Voice communication in free space was demonstrated. The design and test of major components and the complete system are discussed.

  16. 0.3THz wireless communication systems for space applications

    NASA Astrophysics Data System (ADS)

    Yuan, Weiwen; Wang, Hanqing; Li, Huiyuan; Zhang, Zhuo; Yang, Xiaojie; Shi, Weixun

    2015-11-01

    Contrary to the terahertz (THz) applications on the ground, the space applications in the atmosphere free environment do not suffer the atmosphere attenuation. In this study, a 0.3 THz wireless communication systems designed for potential space applications has been set up. It consists of transmitter and detector units based on Schottky diode mixers technology. The system performance is shown including the received signal levels and Eb/N0. For demonstration of THz communications, HD video signals have been transmitted over a distance of 14 m at the data rate of 1.5Gbps.

  17. Economic-Analysis Program for a Communication System

    NASA Technical Reports Server (NTRS)

    Chamberlain, R. G.

    1986-01-01

    Prices and profits of alternative designs compared. Objective of Land Mobile Satellite Service Finance Report (LMSS) program is to provide means for comparing alternative designs of LMSS systems. Program is Multiplan worksheet program. Labels used in worksheet chosen for satellite-based cellular communication service, but analysis not restricted to such cases. LMSS written for interactive execution with Multiplan (version 1.2) and implemented on IBM PC series computer operating under DOS (version 2.11).

  18. Intelligent fault isolation and diagnosis for communication satellite systems

    NASA Technical Reports Server (NTRS)

    Tallo, Donald P.; Durkin, John; Petrik, Edward J.

    1992-01-01

    Discussed here is a prototype diagnosis expert system to provide the Advanced Communication Technology Satellite (ACTS) System with autonomous diagnosis capability. The system, the Fault Isolation and Diagnosis EXpert (FIDEX) system, is a frame-based system that uses hierarchical structures to represent such items as the satellite's subsystems, components, sensors, and fault states. This overall frame architecture integrates the hierarchical structures into a lattice that provides a flexible representation scheme and facilitates system maintenance. FIDEX uses an inexact reasoning technique based on the incrementally acquired evidence approach developed by Shortliffe. The system is designed with a primitive learning ability through which it maintains a record of past diagnosis studies.

  19. Picture archiving and communications systems (PACS).

    PubMed

    Honeyman, J C; Frost, M M; Huda, W; Loeffler, W; Ott, M; Staab, E V

    1994-01-01

    Although there has been a recent increase in interest in picture archiving and communications systems (PACS) topics, little has been published to assist the non-technical person in understanding the complexities of the technologies required for a PACS implementation. This issue of Current Problems in Radiology defines each PACS component and explains why each is important in a system design. PACS installations at the University of Florida are used as examples to tie the concepts together. The infrastructure required for PACS consists of the information system interfaces, networks, and databases. Information system interfaces guarantee consistent patient data across all platforms and reduce labor requirements by eliminating duplicate data entry. Data networks move information from the originating location to users around the hospital, clinic, campus, city, or world. In the PACS environment, the data consist of patient and study information as well as images and information about these images. Databases organize the data from multiple sources into a coherent package that can be queried for many different purposes, such as retrieving images, reviewing patient and study information, studying practice statistics, and performing outcomes analysis. PACS components consist of acquisition nodes, archives, and output devices. Acquisition nodes may include "digital modalities" such as CT, MRI, nuclear medicine, and computed radiography (CR), along with devices to convert from analog to digital, such as digitizers and frame grabbers. Options for archives are discussed along with configuration schemes. Output devices include both hard copy (film and paper prints) and soft copy (workstations for display and diagnosis). Finally, a description of the PACS installations at the University of Florida is presented, with comments on some of the difficulties and complexities encountered. A discussion of the cost and benefits of PACS is included, along with a forecast of the future of

  20. Evolution of a radio communication relay system

    NASA Astrophysics Data System (ADS)

    Nguyen, Hoa G.; Pezeshkian, Narek; Hart, Abraham; Burmeister, Aaron; Holz, Kevin; Neff, Joseph; Roth, Leif

    2013-05-01

    Providing long-distance non-line-of-sight control for unmanned ground robots has long been recognized as a problem, considering the nature of the required high-bandwidth radio links. In the early 2000s, the DARPA Mobile Autonomous Robot Software (MARS) program funded the Space and Naval Warfare Systems Center (SSC) Pacific to demonstrate a capability for autonomous mobile communication relaying on a number of Pioneer laboratory robots. This effort also resulted in the development of ad hoc networking radios and software that were later leveraged in the development of a more practical and logistically simpler system, the Automatically Deployed Communication Relays (ADCR). Funded by the Joint Ground Robotics Enterprise and internally by SSC Pacific, several generations of ADCR systems introduced increasingly more capable hardware and software for automatic maintenance of communication links through deployment of static relay nodes from mobile robots. This capability was finally tapped in 2010 to fulfill an urgent need from theater. 243 kits of ruggedized, robot-deployable communication relays were produced and sent to Afghanistan to extend the range of EOD and tactical ground robots in 2012. This paper provides a summary of the evolution of the radio relay technology at SSC Pacific, and then focuses on the latest two stages, the Manually-Deployed Communication Relays and the latest effort to automate the deployment of these ruggedized and fielded relay nodes.

  1. Instructional Design: System Strategies.

    ERIC Educational Resources Information Center

    Ledford, Bruce R.; Sleeman, Phillip J.

    This book is intended as a source for those who desire to apply a coherent system of instructional design, thereby insuring accountability. Chapter 1 covers the instructional design process, including: instructional technology; the role of evaluation; goal setting; the psychology of teaching and learning; task analysis; operational objectives;…

  2. Using a semi distributed model to enhance communication with stakeholders and participation for designing nitrogen-efficient cropping systems in a catchment

    NASA Astrophysics Data System (ADS)

    Dupas, Rémi; Parnaudeau, Virginie; Reau, Raymond; Gascuel-Odoux, Chantal; Durand, Patrick

    2013-04-01

    Context Catchment scale fully distributed agro-hydrological models are often advocated to evaluate the effect of N mitigation plans on water quality. This type of model is well suited to predict nitrate concentration in rivers under different scenarios, thanks to the variety of processes considered (e.g. groundwater table fluctuations, retention by landscape structures). The role of stakeholders is often limited to providing input data for the modeling; participation only takes place when defining the scenarios to be tested (e.g. implementation of a regulation). In most cases, characterization of the cropping systems and their evolution is carried out by scientists alone based on data from surveys and external expert knowledge. For instance, crop succession on each field plot is determined using complex statistical methods or remote sensing data, generating a complex system description that is not always adapted to the stakeholder's issues. However, modeling with stakeholders at local scale enables increasing and sharing knowledge by collaborative learning. We assume that involving stakeholders in the characterization of the cropping systems to be modeled, and simplifying system description, helps performing modeling studies that answer their questions on design of N efficient cropping systems. The model Syst'N is a tool designed to increase knowledge on nitrogen losses in cropping systems, at the plot scale. This tool, beyond a mere simulation model, was developed in order to meet requirements and constraints of non scientific users such as local stakeholders involved in water quality actions. They are referred to as 'stakeholders' hereafter. In this simulation study, N losses at the outlet of the catchment result from an aggregation of losses simulated in 63 homogenous simulation units (HSU), representing cropping systems present in the catchment. Learnings from field experience with stakeholders The field experience described here is from a 80km² catchment

  3. System for synchronizing synthesizers of communication systems

    NASA Technical Reports Server (NTRS)

    Enriquez, E. A. (Inventor); Gookin, R. E.

    1979-01-01

    Frequency synthesizers at first and second stations that communicate with each other via a transmission link having a constant propagation delay time are started and synchronized by transmitting a tone from the first station to the second station via the link. The frequencies derived from the synthesizer at the second station are received at the first station and are combined with the frequencies derived from the synthesizer at the first station to derive a constant beat frequency as the two synthesizers are stepped.

  4. Patients’ Perspective of the Design of Provider-Patients Electronic Communication Services

    PubMed Central

    Silhavy, Petr; Silhavy, Radek; Prokopova, Zdenka

    2014-01-01

    Information Delivery is one the most important tasks in healthcare practice. This article discusses patient’s tasks and perspectives, which are then used to design a new Effective Electronic Methodology. The system design methods applicable to electronic communication in the healthcare sector are also described. The architecture and the methodology for the healthcare service portal are set out in the proposed system design. PMID:24927038

  5. Remote Systems Design & Deployment

    SciTech Connect

    Bailey, Sharon A.; Baker, Carl P.; Valdez, Patrick LJ

    2009-08-28

    The Pacific Northwest National Laboratory (PNNL) was tasked by Washington River Protection Solutions, LLC (WRPS) to provide information and lessons learned relating to the design, development and deployment of remote systems, particularly remote arm/manipulator systems. This report reflects PNNL’s experience with remote systems and lays out the most important activities that need to be completed to successfully design, build, deploy and operate remote systems in radioactive and chemically contaminated environments. It also contains lessons learned from PNNL’s work experiences, and the work of others in the national laboratory complex.

  6. Communicating from the edge of the solar system

    NASA Technical Reports Server (NTRS)

    Posner, E. C.; Horttor, R. L.; Grant, T. L.

    1986-01-01

    Communication technology for deep-space scientific missions is surveyed, with a focus on systems being developed for Galileo, a NASA orbiter/probe mission to Jupiter. The problems faced in designing the links from the probe (descending into the Jovian atmosphere) to the orbiter and from the orbiter to earth are examined; the technological solutions adopted for Galileo are discussed; the expansion of the Deep Space Network for the mission is described; the advantages and limitations of cm-band communication systems being considered to meet the data-rate requirements of future deep-space missions are outlined; and the potential of optical communication for the 21st century is indicated. Also included are tables listing past and planned deep-space missions and a brief description of the use of spacecraft radio signals by radio and planetary scientists to probe solar-system plasmas and gravitational fields.

  7. Wireless communication system via nanoscale plasmonic antennas.

    PubMed

    Merlo, Juan M; Nesbitt, Nathan T; Calm, Yitzi M; Rose, Aaron H; D'Imperio, Luke; Yang, Chaobin; Naughton, Jeffrey R; Burns, Michael J; Kempa, Krzysztof; Naughton, Michael J

    2016-01-01

    Present on-chip optical communication technology uses near-infrared light, but visible wavelengths would allow system miniaturization and higher energy confinement. Towards this end, we report a nanoscale wireless communication system that operates at visible wavelengths via in-plane information transmission. Here, plasmonic antenna radiation mediates a three-step conversion process (surface plasmon → photon → surface plasmon) with in-plane efficiency (plasmon → plasmon) of 38% for antenna separation 4λ0 (with λ0 the free-space excitation wavelength). Information transmission is demonstrated at bandwidths in the Hz and MHz ranges. This work opens the possibility of optical conveyance of information using plasmonic antennas for on-chip communication technology. PMID:27555451

  8. Domestic satellite communications systems - Background and projections

    NASA Astrophysics Data System (ADS)

    Bargellini, P. L.

    Planned and existing national and international communications satellites are reviewed, along with comparative costs for leasing or owning a satellite and the basic capabilities of communications spacecraft. Eleven different satellite communications systems existed in 1982, including Intelsat, Marisat/Inmarsat, and Intersputnik as the international segments, and the Molniya, Telesat, Palapa, Westar, Satcom, Comstar, Amersat, and the SBS national systems. Seven of the twenty countries leasing Intelsat services are planning their own satellites. Leasing permits full capabilities withno development costs and ensures the lessor of full use of the satellite capacities. Developing countries can then gain hands-on experience with space technologies. Future demands are discussed, noting the broadening of the available bandwidths, better orbit utilization, and increases in transponder numbers to handle increased loads in future spacecraft.

  9. Wireless communication system via nanoscale plasmonic antennas

    PubMed Central

    Merlo, Juan M.; Nesbitt, Nathan T.; Calm, Yitzi M.; Rose, Aaron H.; D’Imperio, Luke; Yang, Chaobin; Naughton, Jeffrey R.; Burns, Michael J.; Kempa, Krzysztof; Naughton, Michael J.

    2016-01-01

    Present on-chip optical communication technology uses near-infrared light, but visible wavelengths would allow system miniaturization and higher energy confinement. Towards this end, we report a nanoscale wireless communication system that operates at visible wavelengths via in-plane information transmission. Here, plasmonic antenna radiation mediates a three-step conversion process (surface plasmon → photon → surface plasmon) with in-plane efficiency (plasmon → plasmon) of 38% for antenna separation 4λ0 (with λ0 the free-space excitation wavelength). Information transmission is demonstrated at bandwidths in the Hz and MHz ranges. This work opens the possibility of optical conveyance of information using plasmonic antennas for on-chip communication technology. PMID:27555451

  10. Introduction to Communication Science and Systems

    NASA Astrophysics Data System (ADS)

    Russell, C. T.

    This book is designed to serve as a textbook for a three quarter or two semester upper division or graduate course for beginners interested in the wide range of topics essential to communication systems. It covers antennas and transmission, thermal noise and its consequences, Fourier transforms, modulation and noise, sample and pulse code modulation, autocorrelation and power spectrum, optimum filtering, gaussian noise and errors in digital transmission, data transmission limits on data rate, and source encoding.The book is divided into 13 chapters, each of which is divided into about 10 sections, and each section is followed by a list of about three problems on the material in that section. A list of further reading is included for each chapter as is a comprehensive index. The book is written for students of electrical engineering, but the authors state in their introduction that physicists, earth scientists, and astronomers who must detect signals in their work can use this book to learn about the limits of detectability of signals. I would agree with the authors and say there is more than that. I found many examples of techniques that I had heard of over the years and wondered at how they worked but had never delved into, such as convolutional coding (and decoding), which is used to reduce the number of bit errors in satellite transmissions.

  11. Designing future photovoltaic systems

    SciTech Connect

    Jones, G.J.

    1984-01-01

    The large scale use of photovoltaic systems to generate our electricity is a dream for the future; but if this dream is to be realized, we must understand these systems today. As a result, there has been extensive research into the design and economic tradeoffs of utility interconnected photovoltaic applications. The understanding gained in this process has shown that photovoltaic system design can be a very simple and straight-forward endeavor. This paper reviews those past studies and shows how we have reached the present state of system design evolution. The concept of the utility interactive PV system with energy value determined by the utility's avoided cost will be explored. This concept simplifies the screening of potential applications for economic viability, and we will present several rules-of-thumb for this purpose.

  12. Electronics systems test laboratory testing of shuttle communications systems

    NASA Technical Reports Server (NTRS)

    Stoker, C. J.; Bromley, L. K.

    1985-01-01

    Shuttle communications and tracking systems space to space and space to ground compatibility and performance evaluations are conducted in the NASA Johnson Space Center Electronics Systems Test Laboratory (ESTL). This evaluation is accomplished through systems verification/certification tests using orbiter communications hardware in conjunction with other shuttle communications and tracking external elements to evaluate end to end system compatibility and to verify/certify that overall system performance meets program requirements before manned flight usage. In this role, the ESTL serves as a multielement major ground test facility. The ESTL capability and program concept are discussed. The system test philosophy for the complex communications channels is described in terms of the major phases. Results of space to space and space to ground systems tests are presented. Several examples of the ESTL's unique capabilities to locate and help resolve potential problems are discussed in detail.

  13. Parallel processing spacecraft communication system

    NASA Technical Reports Server (NTRS)

    Bolotin, Gary S. (Inventor); Donaldson, James A. (Inventor); Luong, Huy H. (Inventor); Wood, Steven H. (Inventor)

    1998-01-01

    An uplink controlling assembly speeds data processing using a special parallel codeblock technique. A correct start sequence initiates processing of a frame. Two possible start sequences can be used; and the one which is used determines whether data polarity is inverted or non-inverted. Processing continues until uncorrectable errors are found. The frame ends by intentionally sending a block with an uncorrectable error. Each of the codeblocks in the frame has a channel ID. Each channel ID can be separately processed in parallel. This obviates the problem of waiting for error correction processing. If that channel number is zero, however, it indicates that the frame of data represents a critical command only. That data is handled in a special way, independent of the software. Otherwise, the processed data further handled using special double buffering techniques to avoid problems from overrun. When overrun does occur, the system takes action to lose only the oldest data.

  14. Communications and control for electric power systems: The 1992 progress report. [AbNET communications system for power systems

    SciTech Connect

    Kirkham, H.

    1992-12-01

    In this report, progress in developing the ABNET communication system is described. ABNET is a set of protocols designed to facilitate highly reliable communications in the power system, developed at JPL with DOE funding over the last few years. Rather than attempt to accomplish technology transfer by publishing the details of AbNET, it was decided to try to interest a company in the private sector in obtaining a license to develop the system commercially. This effort was successful, and late in 1992 Licom, a company in Herndon, VA, obtained a license to develop products based on the ABNET protocols. The technical details of the communication system as it was originally conceived can be found in earlier reports. This report deals with the work of licensing the system, and of developing it beyond the original concept. A demonstration of the technology is planned to take place in Columbus, OH at the facilities of American Electric Power, a major investor-owned utility. Plans for this demonstration are also described.

  15. A packet switched communications system for GRO

    NASA Astrophysics Data System (ADS)

    Husain, Shabu; Yang, Wen-Hsing; Vadlamudi, Rani; Valenti, Joseph

    1993-11-01

    This paper describes the packet switched Instrumenters Communication System (ICS) that was developed for the Command Management Facility at GSFC to support the Gamma Ray Observatory (GRO) spacecraft. The GRO ICS serves as a vital science data acquisition link to the GRO scientists to initiate commands for their spacecraft instruments. The system is ready to send and receive messages at any time, 24 hours a day and seven days a week. The system is based on X.25 and the International Standard Organization's (ISO) 7-layer Open Systems Interconnection (OSI) protocol model and has client and server components. The components of the GRO ICS are discussed along with how the Communications Subsystem for Interconnection (CSFI) and Network Control Program Packet Switching Interface (NPSI) software are used in the system.

  16. A packet switched communications system for GRO

    NASA Technical Reports Server (NTRS)

    Husain, Shabu; Yang, Wen-Hsing; Vadlamudi, Rani; Valenti, Joseph

    1993-01-01

    This paper describes the packet switched Instrumenters Communication System (ICS) that was developed for the Command Management Facility at GSFC to support the Gamma Ray Observatory (GRO) spacecraft. The GRO ICS serves as a vital science data acquisition link to the GRO scientists to initiate commands for their spacecraft instruments. The system is ready to send and receive messages at any time, 24 hours a day and seven days a week. The system is based on X.25 and the International Standard Organization's (ISO) 7-layer Open Systems Interconnection (OSI) protocol model and has client and server components. The components of the GRO ICS are discussed along with how the Communications Subsystem for Interconnection (CSFI) and Network Control Program Packet Switching Interface (NPSI) software are used in the system.

  17. The Globalstar mobile satellite system for worldwide personal communications

    NASA Technical Reports Server (NTRS)

    Wiedeman, Robert A.; Viterbi, Andrew J.

    1993-01-01

    Loral Aerospace Corporation along with Qualcomm Inc. have developed a satellite system which offers global mobile voice and data services to and from handheld and mobile user terminals with omni-directional antennas. By combining the use of low-earth orbit (LEO) satellites with existing terrestrial communications systems and innovative, highly efficient spread spectrum techniques, the Globalstar system provides users with low-cost, reliable communications throughout the world. The Globalstar space segment consists of a constellation of 48 LEO satellites in circular orbits with 750 NM (1389 km) altitude. Each satellite communicates with the mobile users via the satellite-user links and with gateway stations. The gateway stations handle the interface between the Globalstar network and the OSTN/PLMN systems. Globalstar transceivers are similar to currently proposed digital cellular telephones in size and have a serial number that will allow the end user to make and receive calls from or to that device anywhere in the world. The Globalstar system is designed to operate as a complement to existing local, long-distance, public, private and specialized telecommunications networks. Service is primarily designed to serve the rural and thin route communications needs of consumers, government users, and private networks.

  18. Performance analysis of Integrated Communication and Control System networks

    NASA Technical Reports Server (NTRS)

    Halevi, Y.; Ray, A.

    1990-01-01

    This paper presents statistical analysis of delays in Integrated Communication and Control System (ICCS) networks that are based on asynchronous time-division multiplexing. The models are obtained in closed form for analyzing control systems with randomly varying delays. The results of this research are applicable to ICCS design for complex dynamical processes like advanced aircraft and spacecraft, autonomous manufacturing plants, and chemical and processing plants.

  19. Designing automatic resupply systems.

    PubMed

    Harding, M L

    1999-02-01

    This article outlines the process for designing and implementing autoresupply systems. The planning process includes determination of goals and appropriate participation. Different types of autoresupply mechanisms include kanban, breadman, consignment, systems contracts, and direct shipping from an MRP schedule. PMID:10345630

  20. Digital systems design language

    NASA Technical Reports Server (NTRS)

    Shiva, S. G.

    1979-01-01

    Digital Systems Design Language (DDL) is implemented on the SEL-32 Computer Systems. The detaileds of the language, the translator, and the simulator, and the smulator programs are given. Several example descriptions and a tutorial on hardware description languages are provided, to guide the user.

  1. MMIC technology for advanced space communications systems

    NASA Technical Reports Server (NTRS)

    Downey, A. N.; Connolly, D. J.; Anzic, G.

    1984-01-01

    The current NASA program for 20 and 30 GHz monolithic microwave integrated circuit (MMIC) technology is reviewed. The advantages of MMIC are discussed. Millimeter wavelength MMIC applications and technology for communications systems are discussed. Passive and active MMIC compatible components for millimeter wavelength applications are investigated. The cost of a millimeter wavelength MMIC's is projected.

  2. 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.

  3. Strategic Choices for Data Communications Systems.

    ERIC Educational Resources Information Center

    Arns, Robert G.; Urban, Patricia A.

    1984-01-01

    Issues in determining how to develop a data communications system at colleges and universities are discussed including; technical requirements; cost; implications for coordination and (de)centralization of hardware/software; deciding when to create a data network; data security, information integrity, and organizational development. (Author/MLW)

  4. Designing Synthetic Microcapsules That Undergo Biomimetic Communication and Autonomous Motion.

    PubMed

    Yashin, Victor V; Kolmakov, German V; Shum, Henry; Balazs, Anna C

    2015-11-10

    Inspired by the collective behavior of slime molds and amoebas, we designed synthetic cell-like objects that move and self-organize in response to self-generated chemical gradients, thereby exhibiting autochemotaxis. Using computational modeling, we specifically focused on microcapsules that encompass a permeable shell and are localized on an adhesive surface in solution. Lacking any internal machinery, these spherical, fluid-filled shells might resemble the earliest protocells. Our microcapsules do, however, encase particles that can diffuse through the outer shell and into the surrounding fluid. The released particles play two important, physically realizable roles: (1) they affect the permeability of neighboring capsules and (2) they generate adhesion gradients on the underlying surface. Due to feedback mechanisms provided by the released particles, the self-generated adhesion gradients, and hydrodynamic interactions, the capsules undergo collective, self-sustained motion and even exhibit antlike tracking behavior. With the introduction of a chemically patterned stripe on the surface, a triad of capsules can be driven to pick up four-capsule cargo, transport this cargo, and drop off this payload at a designated site. We also modeled a system where the released particles give rise to a particular cycle of negative feedback loops (mimicking the "repressilator" network), which regulates the production of chemicals within the capsules and hence their release into the solution. By altering the system parameters, three capsules could be controllably driven to self-organize into a stable, close-packed triad that would either translate as a group or remain stationary. Moreover, the stationary triads could be made to switch off after assembly and thus produce minimal quantities of chemicals. Taken together, our models allow us to design a rich variety of self-propelled structures that achieve complex, cooperative behavior through fundamental physicochemical phenomena

  5. Comprehensive testing of a defense systems communications satellite

    NASA Technical Reports Server (NTRS)

    Shirk, N. K.; Keer, S. J.

    1980-01-01

    The system level testing of the defense satellite communications system (DSCS) 3 program is reviewed. Concentration is on the results of the systems tests of the DSCS 3 development test model (DTM). The DSCS 3DTM consisted of engineering components interconnected in an open bench layout. The DTM tests were performed to demonstrate satellite electrical performance characteristics and to uncover design deficiencies and interface problems. The availability of the DTM test results prior to the fabrication of the flight model hardware permited the incorporation of necessary design changes with a minimum impact on program costs and schedules.

  6. Collaborative Design in a Networked Multimedia Environment: Emerging Communication Patterns.

    ERIC Educational Resources Information Center

    Gay, Geri; Grosz-Ngate, Maria

    1994-01-01

    Describes a study that investigated the activities of engineering students working on a collaborative design project in a distributed multimedia environment. Topics discussed include learning as a social process; face-to-face and video communication; problem-solving techniques; use of interactive media; the construction of knowledge; and group…

  7. Visible Light Communication Physical Layer Design for Jist Simulation

    NASA Astrophysics Data System (ADS)

    Tomaš, Boris

    2014-12-01

    Current advances in computer networking consider using visible light spectrum to encode and decode digital data. This approach is relatively non expensive. However, designing appropriate MAC or any other upper layer protocol for Visible Light Communication (VLC) requires appropriate hardware. This paper proposes and implements such hardware simulation (physical layer) that is compatible with existing network stack.

  8. Visual Communication for Medicines: Malignant Assumptions and Benign Design?

    ERIC Educational Resources Information Center

    van der Waarde, Karel

    2010-01-01

    An area of visual communication that might be classified as a "design failure" is the visual presentation of information about "prescription-only medicines" for patients. This information is provided on packaging, leaflets, brochures, labels and websites. The practical issue is that there are problems in convincing patients to take medicines…

  9. Communications network design and costing model users manual

    NASA Technical Reports Server (NTRS)

    Logan, K. P.; Somes, S. S.; Clark, C. A.

    1983-01-01

    The information and procedures needed to exercise the communications network design and costing model for performing network analysis are presented. Specific procedures are included for executing the model on the NASA Lewis Research Center IBM 3033 computer. The concepts, functions, and data bases relating to the model are described. Model parameters and their format specifications for running the model are detailed.

  10. Energy efficiency in wireless communication systems

    DOEpatents

    Caffrey, Michael Paul; Palmer, Joseph McRae

    2012-12-11

    Wireless communication systems and methods utilize one or more remote terminals, one or more base terminals, and a communication channel between the remote terminal(s) and base terminal(s). The remote terminal applies a direct sequence spreading code to a data signal at a spreading factor to provide a direct sequence spread spectrum (DSSS) signal. The DSSS signal is transmitted over the communication channel to the base terminal which can be configured to despread the received DSSS signal by a spreading factor matching the spreading factor utilized to spread the data signal. The remote terminal and base terminal can dynamically vary the matching spreading factors to adjust the data rate based on an estimation of operating quality over time between the remote terminal and base terminal such that the amount of data being transmitted is substantially maximized while providing a specified quality of service.

  11. Land-mobile satellite communication system

    NASA Technical Reports Server (NTRS)

    Yan, Tsun-Yee (Inventor); Rafferty, William (Inventor); Dessouky, Khaled I. (Inventor); Wang, Charles C. (Inventor); Cheng, Unjeng (Inventor)

    1993-01-01

    A satellite communications system includes an orbiting communications satellite for relaying communications to and from a plurality of ground stations, and a network management center for making connections via the satellite between the ground stations in response to connection requests received via the satellite from the ground stations, the network management center being configured to provide both open-end service and closed-end service. The network management center of one embodiment is configured to provides both types of service according to a predefined channel access protocol that enables the ground stations to request the type of service desired. The channel access protocol may be configured to adaptively allocate channels to open-end service and closed-end service according to changes in the traffic pattern and include a free-access tree algorithm that coordinates collision resolution among the ground stations.

  12. CLASSIFICATION OF THE MGR SITE COMMUNICATIONS SYSTEM

    SciTech Connect

    J. Ziegler

    1999-08-31

    The purpose of this analysis is to document the Quality Assurance (QA) classification of the Monitored Geologic Repository (MGR) site communications system structures, systems and components (SSCs) performed by the MGR Safety Assurance Department. This analysis also provides the basis for revision of YMP/90-55Q, Q-List (YMP 1998). The Q-List identifies those MGR SSCs subject to the requirements of DOE/RW-0333P, ''Quality Assurance Requirements and Description'' (QARD) (DOE 1998).

  13. Communication and tracking system 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 were used in the analysis 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 the future growth. Technology transparency and impact of growth on other systems are also addressed.

  14. On the stability of robotic systems with random communication rates

    NASA Technical Reports Server (NTRS)

    Kobayashi, H.; Yun, X.; Paul, R. P.

    1989-01-01

    Control problems of sampled data systems which are subject to random sample rate variations and delays are studied. Due to the rapid growth of the use of computers more and more systems are controlled digitally. Complex systems such as space telerobotic systems require the integration of a number of subsystems at different hierarchical levels. While many subsystems may run on a single processor, some subsystems require their own processor or processors. The subsystems are integrated into functioning systems through communications. Communications between processes sharing a single processor are also subject to random delays due to memory management and interrupt latency. Communications between processors involve random delays due to network access and to data collisions. Furthermore, all control processes involve delays due to casual factors in measuring devices and to signal processing. Traditionally, sampling rates are chosen to meet the worst case communication delay. Such a strategy is wasteful as the processors are then idle a great proportion of the time; sample rates are not as high as possible resulting in poor performance or in the over specification of control processors; there is the possibility of missing data no matter how low the sample rate is picked. Asymptotical stability with probability one for randomly sampled multi-dimensional linear systems is studied. A sufficient condition for the stability is obtained. This condition is so simple that it can be applied to practical systems. A design procedure is also shown.

  15. A unique multi-access laser communications transceiver system

    NASA Technical Reports Server (NTRS)

    Ross, Monte

    1990-01-01

    A 'many points in one point' multiaccess laser system has been examined, and results are reported which indicating the feasibility of optical communications multiaccess communications is feasible and that the resultant terminal size and with savings are very substantial compared to the dedicated optical terminals or RF multiaccess approaches. A preliminary design has been accomplished of a package that can weigh less than 150 pounds and which uses a 10-in. effective diameter fixed telescope and requires less than 100 W of regulated power and less than 8 cu ft of space.

  16. When Mind, Heart, and Hands Meet: Communication Design and Designers

    ERIC Educational Resources Information Center

    Cheung, Ming

    2012-01-01

    Hong Kong's transformation from a manufacturing to a knowledge-based economy has prompted the local government to promote the city as a regional design center. The 2008 Policy Address delivered by Hong Kong's Chief Executive calls for the creation of a large pool of creative and knowledgeable talent. The government recognizes that, in addition to…

  17. Field study of communication and workload in police helicopters - Implications for AI cockpit design

    NASA Technical Reports Server (NTRS)

    Linde, Charlotte; Shively, Robert J.

    1988-01-01

    This paper reports on the work performed by civilian helicopter crews, using audio and video recordings and a variety of workload measures (heart rate and subjective ratings) obtained in a field study of public service helicopter missions. The number and frequency of communications provided a significant source of workload. This is relevant to the design of automated cockpit systems, since many designs presuppose the use of voice I/O systems. Fluency of communications (including pauses, hesitation markers, repetitions, and false starts) furnished an early indication of the effects of fatigue. Three workload measures were correlated to identify high workload segments of flight, and to suggest alternate task allocations between crew members.

  18. Integrated system design report

    SciTech Connect

    Not Available

    1989-07-01

    The primary objective of the integrated system test phase is to demonstrate the commercial potential of a coal fueled diesel engine in its actual operating environment. The integrated system in this project is defined as a coal fueled diesel locomotive. This locomotive, shown on drawing 41D715542, is described in the separate Concept Design Report. The test locomotive will be converted from an existing oil fueled diesel locomotive in three stages, until it nearly emulates the concept locomotive. Design drawings of locomotive components (diesel engine, locomotive, flatcar, etc.) are included.

  19. Space systems computer-aided design technology

    NASA Technical Reports Server (NTRS)

    Garrett, L. B.

    1984-01-01

    The interactive Design and Evaluation of Advanced Spacecraft (IDEAS) system is described, together with planned capability increases in the IDEAS system. The system's disciplines consist of interactive graphics and interactive computing. A single user at an interactive terminal can create, design, analyze, and conduct parametric studies of earth-orbiting satellites, which represents a timely and cost-effective method during the conceptual design phase where various missions and spacecraft options require evaluation. Spacecraft concepts evaluated include microwave radiometer satellites, communication satellite systems, solar-powered lasers, power platforms, and orbiting space stations.

  20. Acoustic system for communication in pipelines

    DOEpatents

    Martin, II, Louis Peter; Cooper, John F.

    2008-09-09

    A system for communication in a pipe, or pipeline, or network of pipes containing a fluid. The system includes an encoding and transmitting sub-system connected to the pipe, or pipeline, or network of pipes that transmits a signal in the frequency range of 3-100 kHz into the pipe, or pipeline, or network of pipes containing a fluid, and a receiver and processor sub-system connected to the pipe, or pipeline, or network of pipes containing a fluid that receives said signal and uses said signal for a desired application.

  1. Communications and tracking expert systems study

    NASA Technical Reports Server (NTRS)

    Leibfried, T. F.; Feagin, Terry; Overland, David

    1987-01-01

    The original objectives of the study consisted of five broad areas of investigation: criteria and issues for explanation of communication and tracking system anomaly detection, isolation, and recovery; data storage simplification issues for fault detection expert systems; data selection procedures for decision tree pruning and optimization to enhance the abstraction of pertinent information for clear explanation; criteria for establishing levels of explanation suited to needs; and analysis of expert system interaction and modularization. Progress was made in all areas, but to a lesser extent in the criteria for establishing levels of explanation suited to needs. Among the types of expert systems studied were those related to anomaly or fault detection, isolation, and recovery.

  2. Security aspects of RFID communication systems

    NASA Astrophysics Data System (ADS)

    Bîndar, Valericǎ; Popescu, Mircea; Bǎrtuşicǎ, Rǎzvan; Craciunescu, Razvan; Halunga, Simona

    2015-02-01

    The objective of this study is to provide an overview of basic technical elements and security risks of RFID communication systems and to analyze the possible threats arising from the use of RFID systems. A number of measurements are performed on a communication system including RFID transponder and the tag reader, and it has been determined that the uplink signal level is 62 dB larger than the average value of the noise at the distance of 1m from the tag, therefore the shielding effectiveness has to exceed this threshold. Next, the card has been covered with several shielding materials and measurements were carried, under similar conditions to test the recovery of compromising signals. A very simple protection measure to prevent unauthorized reading of the data stored on the card has been proposed, and some electromagnetic shielding materials have been proposed and tested.

  3. Automatic gisting systems for voice communications

    NASA Astrophysics Data System (ADS)

    Maksymowicz, A. T.

    It is pointed out that the detection of a limited number of key words in voice communications, combined with nonlinguistic cues and situation knowledge, holds out the promise for automatic extraction of the general content or gist of the transmitted messages. A systems-level description of an end-to-end automatic gisting system for screening voice communications is presented. The emphasis is on identifying information which can usefully supplement the detected key words in the gisting process. Principal subsystems are identified, and their functions are discussed in the context of an overall system architecture. The example of automatic determination of aircraft takeoffs and landings at an airport, based on monitoring conversations between pilots and air traffic controllers, is used for illustrative purposes.

  4. SYSTID - A flexible tool for the analysis of communication systems.

    NASA Technical Reports Server (NTRS)

    Dawson, C. T.; Tranter, W. H.

    1972-01-01

    Description of the System Time Domain Simulation (SYSTID) computer-aided analysis program which is specifically structured for communication systems analysis. The SYSTID program is user oriented so that very little knowledge of computer techniques and very little programming ability are required for proper application. The program is designed so that the user can go from a system block diagram to an accurate simulation by simply programming a single English language statement for each block in the system. The mathematical and functional models available in the SYSTID library are presented. An example problem is given which illustrates the ease of modeling communication systems. Examples of the outputs available are presented, and proposed improvements are summarized.

  5. Designing for Designing: Information and Communication Technologies (ICTs) and Professional Education

    ERIC Educational Resources Information Center

    Wang, Tsungjuang

    2011-01-01

    Information and Communication Technologies (ICTs) appear to be well fitted to the education of design professionals, such as architectural and engineering students, mainly because of the unique culture of these professional schools, where the emphasis is on creativity, collaboration, social relevance and rapid communication of ideas. Attention is…

  6. Distributed System Design Checklist

    NASA Technical Reports Server (NTRS)

    Hall, Brendan; Driscoll, Kevin

    2014-01-01

    This report describes a design checklist targeted to fault-tolerant distributed electronic systems. Many of the questions and discussions in this checklist may be generally applicable to the development of any safety-critical system. However, the primary focus of this report covers the issues relating to distributed electronic system design. The questions that comprise this design checklist were created with the intent to stimulate system designers' thought processes in a way that hopefully helps them to establish a broader perspective from which they can assess the system's dependability and fault-tolerance mechanisms. While best effort was expended to make this checklist as comprehensive as possible, it is not (and cannot be) complete. Instead, we expect that this list of questions and the associated rationale for the questions will continue to evolve as lessons are learned and further knowledge is established. In this regard, it is our intent to post the questions of this checklist on a suitable public web-forum, such as the NASA DASHLink AFCS repository. From there, we hope that it can be updated, extended, and maintained after our initial research has been completed.

  7. ROBUS-2: A Fault-Tolerant Broadcast Communication System

    NASA Technical Reports Server (NTRS)

    Torres-Pomales, Wilfredo; Malekpour, Mahyar R.; Miner, Paul S.

    2005-01-01

    The Reliable Optical Bus (ROBUS) is the core communication system of the Scalable Processor-Independent Design for Enhanced Reliability (SPIDER), a general-purpose fault-tolerant integrated modular architecture currently under development at NASA Langley Research Center. The ROBUS is a time-division multiple access (TDMA) broadcast communication system with medium access control by means of time-indexed communication schedule. ROBUS-2 is a developmental version of the ROBUS providing guaranteed fault-tolerant services to the attached processing elements (PEs), in the presence of a bounded number of faults. These services include message broadcast (Byzantine Agreement), dynamic communication schedule update, clock synchronization, and distributed diagnosis (group membership). The ROBUS also features fault-tolerant startup and restart capabilities. ROBUS-2 is tolerant to internal as well as PE faults, and incorporates a dynamic self-reconfiguration capability driven by the internal diagnostic system. This version of the ROBUS is intended for laboratory experimentation and demonstrations of the capability to reintegrate failed nodes, dynamically update the communication schedule, and tolerate and recover from correlated transient faults.

  8. Experimental millimeter-wave personal satellite communications system

    NASA Technical Reports Server (NTRS)

    Suzuki, Yoshiaki; Kimura, Shigeru; Shimada, Masaaki; Tanaka, Masato; Takahashi, Yasuhiro

    1991-01-01

    Communications Research Laboratory (CRL) has investigated an advanced millimeter (mm)-wave satellite communications system for personal use. Experiments in mm-wave personal satellite communication are to be conducted for 3 years using Japan's Engineering Test Satellite VI (ETS-VI). This paper describes an experimental mm-wave (43/38 GHz) personal satellite communication system, including an onboard transponder and an earth terminal. The on-board transponder is almost completed, and the ground experiment system is still in the design stage. The transponder employs advanced mm-wave solid state technology. It uses 38 GHz high power solid state amplifiers to accelerate the development of mm-wave solid state devices which are indispensable to personal earth terminals. The transponder consists of a 43 GHz receiver with a built-in low noise amplifier, an IF filter section with very narrow bandwidth to improve the carrier-to-noise power ratio of the weak personal communication signal, and two high power amplifiers using newly developed high power Gallium Arsenide (GaAs) metal-semiconductor field effect transistors (MESFETs).

  9. Experimental millimeter-wave personal satellite communications system

    NASA Astrophysics Data System (ADS)

    Suzuki, Yoshiaki; Kimura, Shigeru; Shimada, Masaaki; Tanaka, Masato; Takahashi, Yasuhiro

    1991-09-01

    Communications Research Laboratory (CRL) has investigated an advanced millimeter (mm)-wave satellite communications system for personal use. Experiments in mm-wave personal satellite communication are to be conducted for 3 years using Japan's Engineering Test Satellite VI (ETS-VI). This paper describes an experimental mm-wave (43/38 GHz) personal satellite communication system, including an onboard transponder and an earth terminal. The on-board transponder is almost completed, and the ground experiment system is still in the design stage. The transponder employs advanced mm-wave solid state technology. It uses 38 GHz high power solid state amplifiers to accelerate the development of mm-wave solid state devices which are indispensable to personal earth terminals. The transponder consists of a 43 GHz receiver with a built-in low noise amplifier, an IF filter section with very narrow bandwidth to improve the carrier-to-noise power ratio of the weak personal communication signal, and two high power amplifiers using newly developed high power Gallium Arsenide (GaAs) metal-semiconductor field effect transistors (MESFETs).

  10. Design and performance of a repeater for optical satellite communication

    NASA Astrophysics Data System (ADS)

    Ohm, G.; Wiesmann, Th.; Hieber, E.

    General design aspects of optical inter-satellite and inter-orbit links and the choice of technology for data relay applications are described. A first step toward optical links is the ESA in-orbit experiment SILEX which is briefly reviewed with emphasis on the communication subsystem. All relevant equipments of the communication subsystem, which is based on 0.85-micron laser diodes, QPPM data format, and direct detection, have been developed and tested. Using the equipment developed, an experimental repeater was assembled and investigated. Measured and simulated results are in close agreement, and no major critical events occurred during the development and test activities.

  11. System issues related to satellite communications in a nuclear environment

    SciTech Connect

    Kullstam, P.A.

    1990-05-03

    Nuclear induced signal scintillation effects are of great importance in design and deployment of military satellite systems that must provide survivable and enduring communications service. The induced scintillation will result in Rayleigh signal fading with limited signal decorrelation time and coherent bandwidth of the transmission channel as well as reduced signal power due to terminal antenna scattering loss. In this environment the coherent bandwidth and signal decorrelation time are most important design parameters for modulation subsystem design. The antenna scattering loss is important for link power budgets and satellite network loading.

  12. Design of Low-power Wake-up Circuits in Underwater Acoustic Communication

    NASA Astrophysics Data System (ADS)

    Cuixia, Zhang; Jiaxin, Wu; Yuanxuan, Li

    In underwater acoustic communication, the power consumption of the underwater communication equipments at harsh conditions of marine environment is an important problem. Under that scenario, we propose a design of low-power wake-up circuits based on SCM C8051F020 system. Compare to traditional wake-up circuits which directly judge the energy of received signals, our approach can greatly reduce the misjudgment caused by the environmental disturbance, and the performance of energy conservation is effective. The low-power wake-up circuits possess a promising application prospect in the long-distance wireless underwater communication.

  13. Advanced Communications Technology Satellite (ACTS): Design and on-orbit performance measurements

    NASA Technical Reports Server (NTRS)

    Gargione, F.; Acosta, R.; Coney, T.; Krawczyk, R.

    1995-01-01

    The Advanced Communications Technology Satellite (ACTS), developed and built by Lockheed Martin Astro space for the NASA Lewis Research Center, was launched in September 1993 on the shuttle STS 51 mission. ACTS is a digital experimental communications test bed that incorporates gigahertz bandwidth transponders operating at Ka band, hopping spot beams, on-board storage and switching, and dynamic rain fade compensation. This paper describes the ACTS enabling technologies, the design of the communications payload, the constraints imposed on the spacecraft bus, and the measurements conducted to verify the performance of the system in orbit.

  14. Spectrally Efficient Underwater Acoustic Communications: Channel Characterization and Design Aspects for OFDM

    NASA Astrophysics Data System (ADS)

    Radosevic, Andreja

    In this dissertation, we consider design aspects of spectrally efficient underwater acoustic (UWA) communications. In particular, we first focus on statistical characterization and capacity evaluation of shallow water acoustic communications channels. Wideband single-carrier and multi-carrier probe signals are employed during the Kauai Acoustic Communications MURI 2008 (KAM08) and 2011 (KAM11) experiments, to measure the time-varying channel response, and to estimate its statistical properties and capacity that play an important role in the design of spectrally efficient communication systems. Besides the capacity analysis for unconstrained inputs, we determine new bounds on the achievable information rate for discrete-time Gaussian channels with inter-symbol interference and independent and uniformly distributed channel input symbols drawn from finite-order modulation alphabets. Specifically, we derived new bounds on the achievable rates for sparse channels with long memory. Furthermore, we explore design aspects of adaptive modulation based on orthogonal frequency division multiplexing (OFDM) for UWA communications, and study its performance using real-time at-sea experiments. Lastly, we investigate a channel estimation (CE) method for improving the spectral efficiency of UWA communications. Specifically, we determine the performance of a selective decision directed (DD) CE method for UWA OFDM-based communications.

  15. Health systems, communicable diseases and integration.

    PubMed

    Shigayeva, Altynay; Atun, Rifat; McKee, Martin; Coker, Richard

    2010-11-01

    The HIV/AIDS, tuberculosis and malaria pandemics pose substantial challenges globally and to health systems in the countries they affect. This demands an institutional approach that can integrate disease control programmes within health and social care systems. Whilst integration is intuitively appealing, evidence of its benefits remains uncertain and evaluation is beset by lack of a common understanding of what it involves. The aim of this paper is to better define integration in health systems relevant to communicable disease control. We conducted a critical review of published literature on concepts, definitions, and analytical and methodological approaches to integration as applied to health system responses to communicable disease. We found that integration is understood and pursued in many ways in different health systems. We identified a variety of typologies that relate to three fundamental questions associated with integration: (1) why is integration a goal (that is, what are the driving forces for integration); (2) what structures and/or functions at different levels of health system are affected by integration (or the lack of); and (3) how does integration influence interactions between health system components or stakeholders. The frameworks identified were evaluated in terms of these questions, as well as the extent to which they took account of health system characteristics, the wider contextual environment in which health systems sit, and the roles of key stakeholders. We did not find any one framework that explicitly addressed all of these three questions and therefore propose an analytical framework to help address these questions, building upon existing frameworks and extending our conceptualization of the 'how' of integration to identify a continuum of interactions that extends from no interactions, to partial integration that includes linkage and coordination, and ultimately to integration. We hope that our framework may provide a basis for

  16. Instructional Design to Develop Communication Ability for Students in the Electrical Engineering Majors

    NASA Astrophysics Data System (ADS)

    Nakano, Mika; Takahara, Kenji; Kajiwara, Toshinori

    This paper describes the instructional design to develop communication ability for students in the electrical engineering majors. It is based on the case of Fukuoka Institute of Technology which started new courses for communication skills in 2007. A series of communication education from the freshman year to the third grade is systematized, considering the developmental process of students' argumentation. In the classes, students continually learn dialogue and cooperation through various styles of discussion, debate, presentation and so on. The first introductory class of all is “Communication Theory I”, which is aimed at developing self-awareness and improving discussion skills for interpersonal relationship. In this course, students acquire skills to construct their arguments about the given issues and to evaluate others' presentation performances each other. To cultivate students' communication ability, education should not be closed in a class, but support system from departmental level is essential.

  17. Maglev system design considerations

    SciTech Connect

    Coffey, H.T.

    1991-01-01

    Although efforts are now being made to develop magnetic levitation technologies in the United States, they have been underway for two decades in Germany and Japan. The characteristics of maglev systems being considered for implementation in the United States are speculative. A conference was held at Argonne National Laboratory on November 28--29, 1990, to discuss these characteristics and their implications for the design requirements of operational systems. This paper reviews some of the factors considered during that conference.

  18. Utilization of commercial communications systems for space based research applications

    NASA Astrophysics Data System (ADS)

    Overmyer, Carolyn; Thompson, Clark

    1998-01-01

    With the increase in utilization of space for research and development activities, the need for a communication system which improves the availability of payload uplink and downlink with the ground becomes increasingly more critical. At the same time, experiment developers are experiencing a tightening of their budgets for space based research. They don't have the capability to develop a unique communication interface that requires unique software and hardware packages. They would prefer to use commercial protocols and standards available through off-the-shelf components. Also, the need for secure communication is critical to keep proprietary data from being distributed to competing organizations. In order to meet the user community needs, SPACEHAB is currently in the process of developing and testing a system designed specifically for the user community called the SPACEHAB Universal Communication System (SHUCS). The purpose of this paper is to present customer requirements, the SHUCS design approach and top level operations, terrestrial test results, and flight testing scheduled for STS-91 and -95.

  19. LACOMA- OPTICAL ANALYSIS FOR LASER HETERODYNE COMMUNICATION SYSTEM

    NASA Technical Reports Server (NTRS)

    Cohen, S.

    1994-01-01

    LACOMA (Laser Communicator Analysis Program) was developed to predict the effects of optical aberrations on transmitters and receivers used in heterodyne communication systems. Combining the proven techniques of a previous optical program with a new approach designed to evaluate heterodyne performance, the program is a general purpose package to be used by optical and communication engineers. Two independent optical trains for the received signal and the local oscillator are specified and evaluated. A comprehensive ray trace subroutine and Fourier transform compute complex amplitude spread functions in a specified detector plane. The two functions are combined and integrated over a specific detector to determine heterodyne signal power. This power is normalized with respect to an ideal value to provide a quantitative value for receiver degradation. Values of local oscillator illumination efficiency, optical transmission, detection efficiency and phase match efficiency are also evaluated to isolate the cause of any unexpected degradations. The program has been used for a tolerance analysis of a selected system designed for space communications, and for evaluation of several other systems. This program was implemented on an IBM 360/91 and an IBM 360/95 and needs approximately 103K bytes of core.

  20. Proceedings of the Military Communications System Control Symposium

    NASA Astrophysics Data System (ADS)

    Harris, S.; Heller, J.

    1980-11-01

    Contents: Perspective on Communications System Control, Navy Force Coordination and the Requirements for Communications Network Management, On the Functions of a Network Management Agency, Improved Control and Technical Management of DCS Theater Assets Under Crisis and Wartime Conditions, Survivability Performance of MX Communication System, System Control for the Tactical/Strategic Interface, Tactical Circuit-Switched Network Control, Systems Control in Tactical Digital Communications Systems - a Study in Distributed Control, the NATO III Satellite Communications Control System, Network Control in NATO Integrated Communications Systems - Stage I, Evolution of Control in the Defense Satellite Communication System, System Control Considerations for Next Generation DCS Switches, Evolving Approaches to System control in the Defense Communications Systems(DCS), and Network control and the CRM Make Possible Automated Digital Patching.

  1. Network design tool for EHF satellite communications networks

    NASA Astrophysics Data System (ADS)

    Norvell, S.; Brown, G. J.

    1983-06-01

    This document describes the design concept of the network design tool. The network design tool (NDT) is a collection of analytical techniques, algorithms and simulation methods that may be used to characterize the performance of a computer communication network. Much work has been done over the past several years in network performance analysis and many techniques have been developed or proposed. Each of these methods applies to a particular aspect of the network design and is based on a particular modeling point of view. We define the computer communication network and then describe the different ways the network may be modeled. Each network model is related to the particular design problem being addressed. The various analytical approaches are briefly described and their relationship to the network models discussed. Chapter 2 is a survey of the major approaches to specific network design problems while chapters 3 and 4 discuss two fairly well defined areas of network analysis: topological design/optimization and protocol validation. Chapter 5 is a survey of network design tools presently available locally or on the advanced research projects agency network (ARPANET). Finally, chapter 6 presents an outline of the NDT specification.

  2. 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

  3. 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.; Prendergast, Kelly M.; Siekierski, James D.; Wade, Randall S.; Weisskopf, George A.; Yim, Hester J.; Adkins, Antha A.; Carl, James R..; Loh, Y. C.; Roberts, Charles; Steele, Douglas J.; DeSilva, Buveneka Kanishka; Killenb, Harold B.; Williams, Robert M.

    2004-01-01

    This report describes the Orbiter Interface Unit (OIU) and the Early Communication System (ECOMM), which are systems of electronic hardware and software that serve as the primary communication links for the International Space Station (ISS). When a space shuttle is at or near the ISS during assembly and resupply missions, the OIU sends groundor crew-initiated commands from the space shuttle to the ISS and relays telemetry from the ISS to the space shuttle s payload data systems. The shuttle then forwards the telemetry to the ground. In the absence of a space shuttle, the ECOMM handles communications between the ISS and Johnson Space Center via the Tracking and Data Relay Satellite System (TDRSS). Innovative features described in the report include (1) a "smart data-buffering algorithm that helps to preserve synchronization (and thereby minimize loss) of telemetric data between the OIU and the space-shuttle payload data interleaver; (2) an ECOMM antenna-autotracking algorithm that selects whichever of two phased-array antennas gives the best TDRSS signal and electronically steers that antenna to track the TDRSS source; and (3) an ECOMM radiation-latchup controller, which detects an abrupt increase in current indicative of radiation-induced latchup and temporarily turns off power to clear the latchup, restoring power after the charge dissipates.

  4. Integrated communications and optical navigation system

    NASA Astrophysics Data System (ADS)

    Mueller, J.; Pajer, G.; Paluszek, M.

    2013-12-01

    The Integrated Communications and Optical Navigation System (ICONS) is a flexible navigation system for spacecraft that does not require global positioning system (GPS) measurements. The navigation solution is computed using an Unscented Kalman Filter (UKF) that can accept any combination of range, range-rate, planet chord width, landmark, and angle measurements using any celestial object. Both absolute and relative orbit determination is supported. The UKF employs a full nonlinear dynamical model of the orbit including gravity models and disturbance models. The ICONS package also includes attitude determination algorithms using the UKF algorithm with the Inertial Measurement Unit (IMU). The IMU is used as the dynamical base for the attitude determination algorithms. This makes the sensor a more capable plug-in replacement for a star tracker, thus reducing the integration and test cost of adding this sensor to a spacecraft. Recent additions include an integrated optical communications system which adds communications, and integrated range and range rate measurement and timing. The paper includes test results from trajectories based on the NASA New Horizons spacecraft.

  5. Communication by Design: A Collaborative Project for Student Choreographers and Costume Designers

    ERIC Educational Resources Information Center

    McLaine, Gretchen; McCabe, Janine

    2013-01-01

    This article describes Communication by Design, a year-long project developed to foster an important dialogue between emerging student costume designers and student choreographers. Two university professors, one teaching costume design and one teaching dance, collaborated to help their students gain an understanding of how these two disciplines…

  6. A digital communications system for manned spaceflight applications.

    NASA Technical Reports Server (NTRS)

    Batson, B. H.; Moorehead, R. W.

    1973-01-01

    A highly efficient, all-digital communications signal design employing convolutional coding and PN spectrum spreading is described for two-way transmission of voice and data between a manned spacecraft and ground. Variable-slope delta modulation is selected for analog/digital conversion of the voice signal, and a convolutional decoder utilizing the Viterbi decoding algorithm is selected for use at each receiving terminal. A PN spread spectrum technique is implemented to protect against multipath effects and to reduce the energy density (per unit bandwidth) impinging on the earth's surface to a value within the guidelines adopted by international agreement. Performance predictions are presented for transmission via a TDRS (tracking and data relay satellite) system and for direct transmission between the spacecraft and earth. Hardware estimates are provided for a flight-qualified communications system employing the coded digital signal design.

  7. Space Station Information System integrated communications concept

    NASA Technical Reports Server (NTRS)

    Muratore, J.; Bigham, J.; Whitelaw, V.; Marker, W.

    1987-01-01

    This paper presents a model for integrated communications within the Space Station Information System (SSIS). The SSIS is generally defined as the integrated set of space and ground information systems and networks which will provide required data services to the Space Station flight crew, ground operations personnel, and customer communities. This model is based on the International Standards Organization (ISO) layered model for Open Systems Interconnection (OSI). The requirements used to develop the model are presented, and the various elements of the model described.

  8. Multi-access laser communications transceiver system

    NASA Technical Reports Server (NTRS)

    Ross, Monte (Inventor); Lokerson, Donald C. (Inventor); Fitzmaurice, Michael W. (Inventor); Meyer, Daniel D. (Inventor)

    1993-01-01

    A satellite system for optical communications such as a multi-access laser transceiver system. Up to six low Earth orbiting satellites send satellite data to a geosynchronous satellite. The data is relayed to a ground station at the Earth's surface. The earth pointing geosynchronous satellite terminal has no gimbal but has a separate tracking mechanism for tracking each low Earth orbiting satellite. The tracking mechanism has a ring assembly rotatable about an axis coaxial with the axis of the field of view of the geosynchronous satellite and a pivotable arm mounted for pivotal movement on the ring assembly. An optical pickup mechanism at the end of each arm is positioned for optical communication with one of the orbiting satellites by rotation of the ring.

  9. Experimental demonstration of next-generation FSO communication system

    NASA Astrophysics Data System (ADS)

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

    2006-10-01

    Free-space optical communication has emerged as a competitive and viable technology for offering high data rates, improved capacity, cost-effective and an easy to deploy solution for providing connectivity between two points which are up to a few kilometers apart. In this paper we present experimental work which demonstrates the practicality of next generation free-space optical (FSO) communication systems suitable for short-haul, high-speed and robust data links. This experimental system is placed between two buildings in the Waseda University campus area for a communication link spanning a distance of 1 km. We outline the design of the optical antenna which uses 1550 nm wavelength and directly coupling a freespace optical beam to a single-mode fiber without the need for OE/EO conversion, to offer a communication link with data rates from 2.5 Gbps to 10 Gbps. The antenna is capable of overcoming most common limitations inherent in FSO communication systems, such as atmospheric induced beam wander and scintillation effects. A high-speed tracking mechanism which utilizes a fine positioning mirror (FPM) capable of tracking and controlling the received beam and focusing/steering most of beam power into the fiber is presented. This FPM is capable of suppressing the frequent power fluctuations caused by beam angle-of-arrival (AOA) variations. This paper presents experimental results of the FSO communication system capable offering stable performance in terms of measured bit-error-rate (BER). Performance results showing increasing the systems data rate from 2.5 Gbps to 10 Gpbs are also presented.

  10. System-Level Planning, Coordination, and Communication

    PubMed Central

    Kanter, Robert K.; Dries, David; Luyckx, Valerie; Lim, Matthew L.; Wilgis, John; Anderson, Michael R.; Sarani, Babak; Hupert, Nathaniel; Mutter, Ryan; Devereaux, Asha V.; Christian, Michael D.; Kissoon, Niranjan; Christian, Michael D.; Devereaux, Asha V.; Dichter, Jeffrey R.; Kissoon, Niranjan; Rubinson, Lewis; Amundson, Dennis; Anderson, Michael R.; Balk, Robert; Barfield, Wanda D.; Bartz, Martha; Benditt, Josh; Beninati, William; Berkowitz, Kenneth A.; Daugherty Biddison, Lee; Braner, Dana; Branson, Richard D; Burkle, Frederick M.; Cairns, Bruce A.; Carr, Brendan G.; Courtney, Brooke; DeDecker, Lisa D.; De Jong, Marla J.; Dominguez-Cherit, Guillermo; Dries, David; Einav, Sharon; Erstad, Brian L.; Etienne, Mill; Fagbuyi, Daniel B.; Fang, Ray; Feldman, Henry; Garzon, Hernando; Geiling, James; Gomersall, Charles D.; Grissom, Colin K.; Hanfling, Dan; Hick, John L.; Hodge, James G.; Hupert, Nathaniel; Ingbar, David; Kanter, Robert K.; King, Mary A.; Kuhnley, Robert N.; Lawler, James; Leung, Sharon; Levy, Deborah A.; Lim, Matthew L.; Livinski, Alicia; Luyckx, Valerie; Marcozzi, David; Medina, Justine; Miramontes, David A.; Mutter, Ryan; Niven, Alexander S.; Penn, Matthew S.; Pepe, Paul E.; Powell, Tia; Prezant, David; Reed, Mary Jane; Rich, Preston; Rodriquez, Dario; Roxland, Beth E.; Sarani, Babak; Shah, Umair A.; Skippen, Peter; Sprung, Charles L.; Subbarao, Italo; Talmor, Daniel; Toner, Eric S.; Tosh, Pritish K.; Upperman, Jeffrey S.; Uyeki, Timothy M.; Weireter, Leonard J.; West, T. Eoin; Wilgis, John; Ornelas, Joe; McBride, Deborah; Reid, David; Baez, Amado; Baldisseri, Marie; Blumenstock, James S.; Cooper, Art; Ellender, Tim; Helminiak, Clare; Jimenez, Edgar; Krug, Steve; Lamana, Joe; Masur, Henry; Mathivha, L. Rudo; Osterholm, Michael T.; Reynolds, H. Neal; Sandrock, Christian; Sprecher, Armand; Tillyard, Andrew; White, Douglas; Wise, Robert; Yeskey, Kevin

    2014-01-01

    BACKGROUND: System-level planning involves uniting hospitals and health systems, local/regional government agencies, emergency medical services, and other health-care entities involved in coordinating and enabling care in a major disaster. We reviewed the literature and sought expert opinions concerning system-level planning and engagement for mass critical care due to disasters or pandemics and offer suggestions for system-planning, coordination, communication, and response. The suggestions in this chapter are important for all of those involved in a pandemic or disaster with multiple critically ill or injured patients, including front-line clinicians, hospital administrators, and public health or government officials. METHODS: The American College of Chest Physicians (CHEST) consensus statement development process was followed in developing suggestions. Task Force members met in person to develop nine key questions believed to be most relevant for system-planning, coordination, and communication. A systematic literature review was then performed for relevant articles and documents, reports, and other publications reported since 1993. No studies of sufficient quality were identified upon which to make evidence-based recommendations. Therefore, the panel developed expert opinion-based suggestions using a modified Delphi process. RESULTS: Suggestions were developed and grouped according to the following thematic elements: (1) national government support of health-care coalitions/regional health authorities (HC/RHAs), (2) teamwork within HC/RHAs, (3) system-level communication, (4) system-level surge capacity and capability, (5) pediatric patients and special populations, (6) HC/RHAs and networks, (7) models of advanced regional care systems, and (8) the use of simulation for preparedness and planning. CONCLUSIONS: System-level planning is essential to provide care for large numbers of critically ill patients because of disaster or pandemic. It also entails a

  11. Advanced technology for space communications and tracking systems

    NASA Technical Reports Server (NTRS)

    Krishen, Kumar

    1988-01-01

    Technological advances in the communications and tracking areas being developed by NASA and applicable to future missions and associated space operations are discussed. The applications scenarios considered include the Space Shuttle, Space Station, lunar base, and Mars missions. Performance goals and conceptual designs are discussed, and the relevance of optical, laser, and millimeter wave-based implementations to the various applications are examined. Recommendations for future systems developments are addressed.

  12. 46 CFR 184.602 - Internal communications systems.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... TONS) VESSEL CONTROL AND MISCELLANEOUS SYSTEMS AND EQUIPMENT Control and Internal Communications Systems § 184.602 Internal communications systems. (a) A vessel equipped with pilothouse control must have... 46 Shipping 7 2010-10-01 2010-10-01 false Internal communications systems. 184.602 Section...

  13. Solid state laser communications in space (SOLACOS) high data rate satellite communication system verification program

    NASA Astrophysics Data System (ADS)

    Pribil, Klaus; Flemmig, Joerg

    1994-09-01

    This paper gives an overview on the current development status of the SOLACOS program and presents the highlights of the program. SOLACOS (Solid State Laser Communications in Space) is the national German program to develop a high performance laser communication system for high data rate transmission between LEO and GEO satellites (Inter Orbit Link, IOL). Two experimental demonstrator terminals are designed and developed in the SOLACOS program. The main development objectives are the Pointing Acquisition and Tracking subsystem (PAT) and the high data rate communication system. All key subsystems and components are straightway developed to be upgraded in follow- on projects to full space qualification. The main design objective for the system is a high degree of modularity which allows to easily upgrade the system with new upcoming technologies. Therefore, all main subsystems are interconnected via fibers to ease replacement of subsystems. The system implements an asymmetric data link with a 650 MBit/s return channel and a 10 MBit/s forward channel. The 650 MBit/s channel is based on a diode pumped Nd:YAG, Integrated Optics Modulator and uses the syncbit transmission scheme. In the syncbit system synchronization information which is necessary to maintain phase lock of the local oscillator of the coherent receiver is transmitted time multiplexed into the data stream. The PAT system comprises two beam detection sensors and three beam steering elements. For initial acquisition and tracking of the remote satellite a high speed CCD camera with an integrated image processing unit, the Acquisition and Tracking Sensor (ATS) is used. In the tacking mode the beam position is sensed via the Fibernutator sensor which is also used to couple the incoming signal into the receiver fiber. Incoming and outgoing beams are routed through the telescopes which are positioned with a 2 axis gimbal mechanism and a high speed beam steering mirror. The PAT system is controlled by a digital

  14. DEVELOPMENT OF A COMPREHENSIVE WIRELESS COMMUNICATIONS SYSTEM FOR THE UNDERGROUND MINING INDUSTRY

    SciTech Connect

    Zvi H. Meiksin

    2001-04-01

    Progress continued along both subsystems towards an integrated comprehensive wireless communications system for the underground mining industry. Designing an automated continuous self-tuning mechanism that optimizes signal transmission intensity for a given power input enhanced through-the-earth communications. In-mine communications was enhanced through the design of a circuit that eliminates multi-antenna interference, cleaning-up the received signal.

  15. BWID System Design Study

    SciTech Connect

    O`Brien, M.C.; Rudin, M.J.; Morrison, J.L.; Richardson, J.G.

    1991-12-31

    The mission of the Buried Waste Integrated Demonstration (BWID) System Design Study is to identify and evaluate technology process options for the cradle-to-grave remediation of Transuranic (TRU)-Contaminated Waste Pits and Trenches buried at the Idaho National Engineering Laboratory (INEL). Emphasis is placed upon evaluating system configuration options and associated functional and operational requirements for retrieving and treating the buried wastes. A Performance-Based Technology Selection Filter was developed to evaluate the identified remediation systems and their enabling technologies based upon system requirements and quantification of technical Comprehensive Environmental Response, Compensation, and Liability (CERCLA) balancing criteria. Remediation systems will also be evaluated with respect to regulatory and institutional acceptance and cost-effectiveness.

  16. BWID System Design Study

    SciTech Connect

    O'Brien, M.C.; Rudin, M.J.; Morrison, J.L.; Richardson, J.G.

    1991-01-01

    The mission of the Buried Waste Integrated Demonstration (BWID) System Design Study is to identify and evaluate technology process options for the cradle-to-grave remediation of Transuranic (TRU)-Contaminated Waste Pits and Trenches buried at the Idaho National Engineering Laboratory (INEL). Emphasis is placed upon evaluating system configuration options and associated functional and operational requirements for retrieving and treating the buried wastes. A Performance-Based Technology Selection Filter was developed to evaluate the identified remediation systems and their enabling technologies based upon system requirements and quantification of technical Comprehensive Environmental Response, Compensation, and Liability (CERCLA) balancing criteria. Remediation systems will also be evaluated with respect to regulatory and institutional acceptance and cost-effectiveness.

  17. SUBSURFACE REPOSITORY INTEGRATED CONTROL SYSTEM DESIGN

    SciTech Connect

    C.J. Fernado

    1998-09-17

    The purpose of this document is to develop preliminary high-level functional and physical control system architectures for the proposed subsurface repository at Yucca Mountain. This document outlines overall control system concepts that encompass and integrate the many diverse systems being considered for use within the subsurface repository. This document presents integrated design concepts for monitoring and controlling the diverse set of subsurface operations. The subsurface repository design will be composed of a series of diverse systems that will be integrated to accomplish a set of overall functions and objectives. The subsurface repository contains several Instrumentation and Control (I&C) related systems including: waste emplacement systems, ventilation systems, communication systems, radiation monitoring systems, rail transportation systems, ground control monitoring systems, utility monitoring systems (electrical, lighting, water, compressed air, etc.), fire detection and protection systems, retrieval systems, and performance confirmation systems. Each of these systems involve some level of I&C and will typically be integrated over a data communication network. The subsurface I&C systems will also integrate with multiple surface-based site-wide systems such as emergency response, health physics, security and safeguards, communications, utilities and others. The scope and primary objectives of this analysis are to: (1) Identify preliminary system level functions and interface needs (Presented in the functional diagrams in Section 7.2). (2) Examine the overall system complexity and determine how and on what levels these control systems will be controlled and integrated (Presented in Section 7.2). (3) Develop a preliminary subsurface facility-wide design for an overall control system architecture, and depict this design by a series of control system functional block diagrams (Presented in Section 7.2). (4) Develop a series of physical architectures that

  18. Intelligent design system for design automation

    NASA Astrophysics Data System (ADS)

    Shakeri, Cirrus; Deif, Ismail; Katragadda, Prasanna; Knutson, Stanley

    2000-10-01

    In order to succeed in today's global, competitive market, companies need continuous improvements in their product development processes. These improvements should result in expending fewer resources on the design process while achieving better quality. Automating the design process reduces resources needed and allows designers to spend more time on creative aspects that improve the quality of design. For the last three decades, engineers and designers have been searching for better ways to automate the product development process. For certain classes of design problems, which cover a large portion of real world design situations, the process can be automated using knowledge-based systems. These are design problems in which the knowledge sources are known in advance. Using techniques from Knowledge-Based Engineering, knowledge is codified and inserted into a knowledge-based system. The system activates the design knowledge, automatically generating designs that satisfy the design constraints. To increase the return on investment of building automated design systems, Knowledge management methodologies and techniques are required for capturing, formalizing, storing, and searching design knowledge.

  19. Multiple IMU system hardware interface design, volume 2

    NASA Technical Reports Server (NTRS)

    Landey, M.; Brown, D.

    1975-01-01

    The design of each system component is described. Emphasis is placed on functional requirements unique in this system, including data bus communication, data bus transmitters and receivers, and ternary-to-binary torquing decision logic. Mechanization drawings are presented.

  20. Communication

    NASA Technical Reports Server (NTRS)

    Griner, James

    2010-01-01

    NASA s communication work for the UAS Command and Control area will build upon work currently being conducted under NASA Recovery Act funds. Communication portions of UAS NextGen ConOps, Stateof- the-Art assessment, and Gap Analysis. Preliminary simulations for UAS CNPC link scalability assessment. Surrogate UAS aircraft upgrades. This work will also leverage FY10 in-guide funding for communication link model development. UAS are currently managed through exceptions and are operating using DoD frequencies for line-of-sight (LOS) and satellite-based communications links, low-power LOS links in amateur bands, or unlicensed Instrument/Scientific/Medical (ISM) frequencies. None of these frequency bands are designated for Safety and Regularity of Flight. No radio-frequency (RF) spectrum has been allocated by the International Telecommunications Union (ITU) specifically for UAS command and control links, for either LOS or Beyond LOS (BLOS) communication.

  1. A Design Framework for Awareness Systems

    NASA Astrophysics Data System (ADS)

    Markopoulos, Panos

    This chapter discusses the design of awareness systems, whose main function is a social one, namely, to support social communication, mediated social interactions and eventually relationships of the individuals they connect. We focus especially on connecting friends and family rather than on systems used in the context of collaborative work. Readers interested in this latter kind of applications are referred to the design frameworks by Ginelle and Gutwin (2005) and Gutwin and Greenberg (2002). Below, we outline the relevant design space and the corresponding challenges for the design of awareness systems. The challenges pertain to social aspects of interaction design rather than the technological challenges relating to such systems. As such, they are inspired by Jonathan Grudin’s exposition of design challenges for the domain of groupware applications (Grudin, 1994).

  2. Multi-frequency communication system and method

    DOEpatents

    Carrender, Curtis Lee; Gilbert, Ronald W.

    2004-06-01

    A multi-frequency RFID remote communication system is provided that includes a plurality of RFID tags configured to receive a first signal and to return a second signal, the second signal having a first frequency component and a second frequency component, the second frequency component including data unique to each remote RFID tag. The system further includes a reader configured to transmit an interrogation signal and to receive remote signals from the tags. A first signal processor, preferably a mixer, removes an intermediate frequency component from the received signal, and a second processor, preferably a second mixer, analyzes the IF frequency component to output data that is unique to each remote tag.

  3. Satellite communications systems and technology. Executive Summary

    NASA Technical Reports Server (NTRS)

    Edelson, Burton I.; Pelton, Joseph N.; Bostian, Charles W.; Brandon, William T.; Chan, Vincent W. S.; Hager, E. Paul; Helm, Neil R.; Jennings, Raymond D.; Kwan, Robert; Mahle, Christoph E.

    1993-01-01

    NASA and the National Science Foundation (NSF) commissioned a panel of US experts to study the international status of satellite communications systems and technology. The study covers emerging systems concepts, applications, services, and the attendant technologies. The panel members travelled to Europe, Japan, and Russia to gather information first-hand. They visited 17 sites in Europe, 20 sites in Japan, and four in Russia. These included major manufacturers, government organizations, service providers, and associated R&D facilities. The panel's report was reviewed by the sites visited, by the panel, and by representatives of US industry. The report details the information collected and compares it to US activities.

  4. Evolution of the Defense Satellite Communications System

    NASA Astrophysics Data System (ADS)

    Brandon, W. T.

    Concepts for the next generation of the Defense Satellite Communications System (DSCS) are outlined. The approach is to improve the 7/8 GHz capability rather than evolve directly to extremely high frequency (EHF) (either 30/20 or 44/20 GHz). This approach eases transition problems, extends the useful life of the super high frequency (SHF) ground segment, and simultaneously improves system endurance and connectivity. The basic approach is to introduce dual polarization and extend frequency coverage of military terminals to the commercial Ku band.

  5. Pilot-Tone System for Mobile Communications

    NASA Technical Reports Server (NTRS)

    Davarian, F.

    1986-01-01

    In mobile communication system called tone-calibrated technique, pilot tone provides phase- and amplitude-calibration reference to enable coherent demodulation of signal at receiver despite fading. Signal received by or from mobile terminal faded due to motion of terminal and propagation of signal along multiple paths. Fading introduces random amplitude modulation and phase modulation with bandwidth of twice Doppler frequency shift. Degrading effects of multipath fading reduced. Tonecalibrated technique for use with phase-modulated data or telephony systems using Manchester digital pulse-code modulation.

  6. Space systems design at Utah State University - A total approach

    NASA Technical Reports Server (NTRS)

    Redd, Frank J.

    1992-01-01

    An account is given of an Advanced Design Program, developed under the auspices of NASA/USRA, which uses a six quarter-hour multidisciplinary systems-design course to teach spacecraft design. The course integrates engineering skills with system-design principles, while emphasizing written and oral communications. The setting for such student efforts is patterned after existing high-tech spacecraft-design organizations. The classes address design tradeoff decisions, parametric studies, and design reviews, as well as project-continuations.

  7. Radiation-Hardened Electronics for Advanced Communications Systems

    NASA Technical Reports Server (NTRS)

    Whitaker, Sterling

    2015-01-01

    Novel approach enables high-speed special-purpose processors Advanced reconfigurable and reprogrammable communication systems will require sub-130-nanometer electronics. Legacy single event upset (SEU) radiation-tolerant circuits are ineffective at speeds greater than 125 megahertz. In Phase I of this project, ICs, LLC, demonstrated new base-level logic circuits that provide SEU immunity for sub-130-nanometer high-speed circuits. In Phase II, the company developed an innovative self-restoring logic (SRL) circuit and a system approach that provides high-speed, SEU-tolerant solutions that are effective for sub-130-nanometer electronics scalable to at least 22-nanometer processes. The SRL system can be used in the design of NASA's next-generation special-purpose processors, especially reconfigurable communication processors.

  8. SUBSURFACE REPOSITORY INTEGRATED CONTROL SYSTEM DESIGN

    SciTech Connect

    D.C. Randle

    2000-01-07

    The primary purpose of this document is to develop a preliminary high-level functional and physical control system architecture for the potential repository at Yucca Mountain. This document outlines an overall control system concept that encompasses and integrates the many diverse process and communication systems being developed for the subsurface repository design. This document presents integrated design concepts for monitoring and controlling the diverse set of subsurface operations. The Subsurface Repository Integrated Control System design will be composed of a series of diverse process systems and communication networks. The subsurface repository design contains many systems related to instrumentation and control (I&C) for both repository development and waste emplacement operations. These systems include waste emplacement, waste retrieval, ventilation, radiological and air monitoring, rail transportation, construction development, utility systems (electrical, lighting, water, compressed air, etc.), fire protection, backfill emplacement, and performance confirmation. Each of these systems involves some level of I&C and will typically be integrated over a data communications network throughout the subsurface facility. The subsurface I&C systems will also interface with multiple surface-based systems such as site operations, rail transportation, security and safeguards, and electrical/piped utilities. In addition to the I&C systems, the subsurface repository design also contains systems related to voice and video communications. The components for each of these systems will be distributed and linked over voice and video communication networks throughout the subsurface facility. The scope and primary objectives of this design analysis are to: (1) Identify preliminary system-level functions and interfaces (Section 6.2). (2) Examine the overall system complexity and determine how and on what levels the engineered process systems will be monitored, controlled, and

  9. The design of a linear L-band high power amplifier for mobile communication satellites

    NASA Technical Reports Server (NTRS)

    Whittaker, N.; Brassard, G.; Li, E.; Goux, P.

    1990-01-01

    A linear L-band solid state high power amplifier designed for the space segment of the Mobile Satellite (MSAT) mobile communication system is described. The amplifier is capable of producing 35 watts of RF power with multitone signal at an efficiency of 25 percent and with intermodulation products better than 16 dB below carrier.

  10. Design of Hybrid Mobile Communication Networks for Planetary Exploration

    NASA Technical Reports Server (NTRS)

    Alena, Richard L.; Ossenfort, John; Lee, Charles; Walker, Edward; Stone, Thom

    2004-01-01

    The Mobile Exploration System Project (MEX) at NASA Ames Research Center has been conducting studies into hybrid communication networks for future planetary missions. These networks consist of space-based communication assets connected to ground-based Internets and planetary surface-based mobile wireless networks. These hybrid mobile networks have been deployed in rugged field locations in the American desert and the Canadian arctic for support of science and simulation activities on at least six occasions. This work has been conducted over the past five years resulting in evolving architectural complexity, improved component characteristics and better analysis and test methods. A rich set of data and techniques have resulted from the development and field testing of the communication network during field expeditions such as the Haughton Mars Project and NASA Mobile Agents Project.

  11. Performance study for indoor visible light communication systems

    NASA Astrophysics Data System (ADS)

    Gao, Shuo

    The field of Optical Wireless Communications (OWC) has seen rapid development during the recent years. This growing popularity is due to several characteristics of considerable importance to consumer electronics products, such as large bandwidth that is also not having spectrum regulations imposed, low cost, and license free operation. As a branch of OWC, visible light communication (VLC) systems have their own unique advantages, with several new technologies, products and patents having been developed during since the end of last century. In this research, a VLC system for indoor application is proposed. In this work, we focus on reducing cost, and for that, we had to make appropriate selection of system's components, e.g. modulation, coding, filtering. Our objective was to achieve acceptable bit error rate (BER) performance for indoor use, with a low cost system. Through our research we met this objective. Our designs were evaluated through computer simulations. The acquired results proved the suitability of the proposed schemes and the performance's degree of dependency on several parameters such as distance, incidence angle and irradiance angle. A software tool was created allowing easy assessment of the communication system. It is using a user friendly GUI through which the user enters the system's parameters and the system outputs the corresponding BER value.

  12. The Effects of Behavioral Skills Training on Implementation of the Picture Exchange Communication System

    ERIC Educational Resources Information Center

    Rosales, Rocio; Stone, Karen; Rehfeldt, Ruth Anne

    2009-01-01

    The effectiveness of a behavioral skills training (BST) package to teach the implementation of the first three phases of the picture exchange communication system (PECS) was evaluated with 3 adults who had no history teaching any functional communication system. A multiple baseline design across participants was used to evaluate the effectiveness…

  13. A long range transmission system communication plan for ComEd of Chicago 1995 to 2000

    SciTech Connect

    Casanova, R.; Gerleve, F.J.

    1995-10-01

    The design of a telecommunication fiber optical network serving ComEd`s commercial centers and generation stations is described. A long range communication plan is presented describing a migration of transmission substation protection, monitoring and control from an analog system over power line carrier, microwave, and leased phone lines to a digital system using an optimum mix of communication channels including fiber.

  14. Communications and control for electric power systems: Final report

    SciTech Connect

    Kirkham, H.

    1998-04-01

    This report is a summary of some of the work done on the Communications and Control project, with particular emphasis on the achievements during the years 1986--1996. During those years, the project moved away from concern with dispersed storage and generation and its impact on power system operation (the team was responsible for studies in this area, and for making a power system simulator that included DSG), and became involved in more concrete work aimed at applying high-tech solutions to problems of power system communications and control. This report covers work done at JPL on the following topics: (1) the measurement of electric and magnetic fields, both ac and dc; (2) the use of optical power to supply low-power electronics; (3) the design of a fault-tolerant communication system designed for distribution automation; and (4) a digital phase locked loop that allows the use of low-power transmitting electronics to recreate a good-quality signal at the receiver. In a report of this kind, only the results and highlights of the work are described.

  15. Digital design and communication tools for sustainable development

    SciTech Connect

    Totten, M.

    1995-12-31

    Within the computer and communications industry there is a strong sentiment that the speed and power of mainframe computers will be available at personal computer sizes and prices in the next few years. Coinciding with this is the expectation that large data/information/knowledge resource pools will be available online for download. This paper summarizes what is available now and what is coming in the future in computer technologies. Then the author talks the opportunities in `green` building design for energy efficiency and conservation and the type of design tools which will be coming in the future.

  16. Multipoint free-space optics system for short-range communications between flight platforms.

    PubMed

    Heng, Kiang Huat; Zhong, Wen-De; Cheng, Tee Hiang

    2010-01-10

    The problems associated with using typical free-space optics (FSO) transceivers for multipoint communications on flight platforms, such as satellites and unmanned aerial vehicles, in a cluster are discussed and the transceivers are found to be unsuitable for concurrent multipoint communications in those platforms. To overcome the problems, a multipoint FSO system design is proposed. The design of the multipoint system is described and the performance of the multipoint receiver is evaluated in terms of receive gain under different conditions. The proposed multipoint system design offers a promising way to implement concurrent multipoint communications on flight platforms with power, weight, and size advantages compared to the use of multiple transceivers. PMID:20062513

  17. A Light-Weight Instrumentation System Design

    SciTech Connect

    Kidner, Ronald

    1999-06-02

    To meet challenging constraints on telemetry system weight and volume, a custom Light-Weight Instrumentation System was developed to collect vehicle environment and dynamics on a short-duration exo-atmospheric flight test vehicle. The total telemetry system, including electronics, sensors, batteries, and a 1 watt transmitter weighs about 1 kg. Over 80 channels of measurement, housekeeping, and telemetry system diagnostic data are transmitted at 128 kbps. The microcontroller-based design uses the automotive industry standard Controller Area Network to interface with and support in-flight control fimctions. Operational parameters are downloaded via a standard asynchronous serial communications intefiace. The basic design philosophy and functionality is described here.

  18. High Capacity Communications From Martian Distances. Part 1; Spacecraft Link Design Analysis

    NASA Technical Reports Server (NTRS)

    Vyas, Hemali N.; Schuchman, Leonard; Orr, Richard; Williams, Wallace Dan; Collins, Michael; Noreen, Gary

    2006-01-01

    High capacity space communications has been a desire for Human Exploration and Science missions. Current Mars missions operate at data rates of 120 kbps for telemetry downlink and it is desirable to study high rate communication links in the range of 100 Mbps to 1 Gbps data rates from Martian distances. This paper will present some assumed scenarios along with link design assumptions and link analysis for high capacity communications from Mars. The paper will focus on RF subsystems namely antenna and power for the downlink communication from a relay orbiter at Mars. The relay orbiter will communicate with the low orbit spacecrafts at Mars or any Martian surface elements such as robots, and relay the data back to the ground networks on Earth. The study will dive into the spacecraft downlink system design and communication link analysis between the relay orbiter and ground network on Earth for data rates ranging from 100 Mbps to 1 Gbps based on the assumed scenarios and link assumptions. With high rate links at larger distances, there will be a significant impact on the antenna and power requirements and the link design will make an attempt to minimize the mass of the RF subsystem on the spacecraft. The results of this study will be presented for three data rates 1 Gbps, 500 Mbps and 100 Mbps at maximum Mars to Earth distance of 2.67AU. The design will use a Ka-band downlink with 90% link availability, along with various ground network G/T assumptions and possible bandwidth efficient modulations. The paper will conclude with what types of high rate communication links are feasible from Martian distances and also identify a range of requirements for antenna and power technologies for these high capacity communications from Mars.

  19. Propagation issues for emerging mobile and portable communications: A systems perspective

    NASA Technical Reports Server (NTRS)

    Golshan, Nasser

    1993-01-01

    The viewpoint of a system engineer regarding the format of propagation information and models suitable for the design of mobile and portable satellite communications systems for the following services: audio broadcast, two way voice, and packet data is presented. Topics covered include: propagation impairments for portable indoor reception in satellite communications systems; propagation impairments and mitigation techniques for mobile satellite communications systems; characterization of mobile satellite communications channels in the presence of roadside blockage when interleaving and FEC coding are implemented; characterization of short-term mobile satellite signal variations; and characterization of long-term signal variations.

  20. A fault tolerant design for autonomous attitude control of the DSCS-III communication satellite

    NASA Technical Reports Server (NTRS)

    Matijevic, J.; Mettler, E.

    1983-01-01

    The first of a new series of satellites, which will provide the principal elements in the Defense Space Communications System (DSCS), was launched on Oct. 31, 1982. This satellite, DSCS-III, is part of a system which will consist of super-high frequency communications satellites in synchronous, equatorial orbits, continuously operating in four widely separate geographic regions. The DSCS-III is designed both to maintain critical communications in the presence of an electronic jamming threat and to survive nuclear radiation exposure. The results of the present investigation are to provide a basis for the design of a spacecraft tolerant of on-board failures, survivable against external threats, and capable of performing its mission autonomously for periods as long as six months.

  1. 30 CFR 57.18013 - Emergency communications system.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... Programs Surface and Underground § 57.18013 Emergency communications system. A suitable communication system shall be provided at the mine to obtain assistance in the event of an emergency. ... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Emergency communications system....

  2. 30 CFR 56.18013 - Emergency communications system.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... Programs § 56.18013 Emergency communications system. A suitable communication system shall be provided at... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Emergency communications system. 56.18013 Section 56.18013 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR METAL...

  3. 29 CFR 1915.85 - Vessel radar and communication systems.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... Working Conditions § 1915.85 Vessel radar and communication systems. (a) The employer shall service each vessel's radar and communication systems in accordance with 29 CFR 1915.89, Control of Hazardous Energy... 29 Labor 7 2013-07-01 2013-07-01 false Vessel radar and communication systems. 1915.85...

  4. 29 CFR 1915.85 - Vessel radar and communication systems.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... Working Conditions § 1915.85 Vessel radar and communication systems. (a) The employer shall service each vessel's radar and communication systems in accordance with 29 CFR 1915.89, Control of Hazardous Energy... 29 Labor 7 2014-07-01 2014-07-01 false Vessel radar and communication systems. 1915.85...

  5. 29 CFR 1915.85 - Vessel radar and communication systems.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... Working Conditions § 1915.85 Vessel radar and communication systems. (a) The employer shall service each vessel's radar and communication systems in accordance with 29 CFR 1915.89, Control of Hazardous Energy... 29 Labor 7 2012-07-01 2012-07-01 false Vessel radar and communication systems. 1915.85...

  6. 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.

  7. Progress in Design and Construction of the Optical Communications Laser Laboratory

    NASA Technical Reports Server (NTRS)

    Wilson, K. E.; Britcliffe, M.; Golshan, N.

    1999-01-01

    The deployment of advanced hyperspectral imaging and other Earth sensing instruments on board Earth observing satellites is driving the demand for high-data-rate communications. Optical communications meet the required data rates with small, low mass, and low-power communications packages. JPL, as NASA's lead center in optical communications, plans to construct a 1-m Optical Communications Telescope Laboratory (OCTL) at its Table Mountain Facility (TMF) complex in the San Gabriel Mountains of Southern California. The design of the building has been completed, and the construction contractor has been selected. Ground breaking is expected to start at the beginning of the 1999 TMF construction season. A request for proposal (RFP) has been issued for the procurement of the telescope system. Prior to letting the RFP we conducted a request for information with industry for the telescope system. Several vendors responded favorably and provided information on key elements of the proposed design. These inputs were considered in developing the final requirements in the RFP. Keywords: Free space optical communications, lasercom, telescopes, ground stations, adaptive optics, astrometry, Table Mountain Facility

  8. Design and evaluation of interprofessional cross-cultural communication sessions.

    PubMed

    Liu, Min; Poirier, Therese; Butler, Lakesha; Comrie, Rhonda; Pailden, Junvie

    2015-01-01

    The 2013 National Standards for Culturally and Linguistically Appropriate Services (CLAS) call for healthcare professionals to provide quality care and services that are responsive to diverse cultural health beliefs and practices. Accreditation organizations for health professional programs require their curriculum to adequately prepare future practitioners for serving culturally and linguistically diverse populations. Another common curricular need of health professional programs is interprofessional education (IPE). This study presents data that evaluates two IPE culturally competent communication sessions designed for pharmacy and nursing students. Teams of nursing and pharmacy students (n = 160) engaged in case studies focused on developing cross-cultural communication skills, using the LEARN model. Quantitative survey data collected pre-test and post-test measured cultural competency (including subscales of perceived skills, perceived knowledge, confidence in encounter, and attitude) and knowledge related to culturally competent communication. Univariate ANOVA results indicate that actual knowledge as measured by the test and all four Clinical Cultural Competency Questionnaire (CCCQ) subscales significantly increased after the IPE sessions. Pharmacy students scored higher than nursing students on the knowledge pre-test, and nursing students had a more positive attitude at pre-test. The IPE sessions effectively addressed all learning outcomes and will continue in future course offerings. Using cross-cultural communication as a thematic area for IPE program development resulted in educational benefits for the students. To further strengthen nursing and pharmacy students' interprofessional practice, additional IPE opportunities are to be explored. PMID:26652635

  9. Human Communication, Semiotics, and General Systems: Personal and Social Communication.

    ERIC Educational Resources Information Center

    Ruben, Brent D.

    Questions as to the nature of sign and symbol processes and the functions and behavioral consequences of human significant phenomena are of central concern in semiotics and communication. These matters continue to be of critical importance and are still largely unresolved. Scholars in both areas of inquiry have sought unification of scientific…

  10. FEC decoder design optimization for mobile satellite communications

    NASA Technical Reports Server (NTRS)

    Roy, Ashim; Lewi, Leng

    1990-01-01

    A new telecommunications service for location determination via satellite is being proposed for the continental USA and Europe, which provides users with the capability to find the location of, and communicate from, a moving vehicle to a central hub and vice versa. This communications system is expected to operate in an extremely noisy channel in the presence of fading. In order to achieve high levels of data integrity, it is essential to employ forward error correcting (FEC) encoding and decoding techniques in such mobile satellite systems. A constraint length k = 7 FEC decoder has been implemented in a single chip for such systems. The single chip implementation of the maximum likelihood decoder helps to minimize the cost, size, and power consumption, and improves the bit error rate (BER) performance of the mobile earth terminal (MET).

  11. FEC decoder design optimization for mobile satellite communications

    NASA Astrophysics Data System (ADS)

    Roy, Ashim; Lewi, Leng

    A new telecommunications service for location determination via satellite is being proposed for the continental USA and Europe, which provides users with the capability to find the location of, and communicate from, a moving vehicle to a central hub and vice versa. This communications system is expected to operate in an extremely noisy channel in the presence of fading. In order to achieve high levels of data integrity, it is essential to employ forward error correcting (FEC) encoding and decoding techniques in such mobile satellite systems. A constraint length k = 7 FEC decoder has been implemented in a single chip for such systems. The single chip implementation of the maximum likelihood decoder helps to minimize the cost, size, and power consumption, and improves the bit error rate (BER) performance of the mobile earth terminal (MET).

  12. The Iridium (tm) system: Personal communications anytime, anyplace

    NASA Technical Reports Server (NTRS)

    Hatlelid, John E.; Casey, Larry

    1993-01-01

    The Iridium system is designed to provide handheld personal communications between diverse locations around the world at any time and without prior knowledge of the location of the personal units. This paper provides an overview of the system, the services it provides, its operation, and an overview of the commercial practices and relatively high volume satellite production techniques which will make the system cost effective. A constellation of 66 satellites will provide an orbiting, spherical-shell, infrastructure for this global calling capability. The satellites act as tall cellular towers and allow convenient operation for portable handheld telephones. The system will provide a full range of services including voice, paging, data, geolocation, and fax capabilities. Motorola is a world leader in the production of high volume, high quality, reliable telecommunications hardware. One of Iridium's goals is to apply these production techniques to high reliability space hardware. Concurrent engineering, high performance work teams, advanced manufacturing technologies, and improved assembly and test methods are some of the techniques that will keep the Iridium system cost effective. Mobile, global, flexible personal communications are coming that will allow anyone to call or receive a call from/to anyplace at anytime. The Iridium system will provide communications where none exist today. This connectivity will allow increased information transfer, open new markets for various business endeavors, and in general increase productivity and development.

  13. The Iridium (tm) system: Personal communications anytime, anyplace

    NASA Astrophysics Data System (ADS)

    Hatlelid, John E.; Casey, Larry

    The Iridium system is designed to provide handheld personal communications between diverse locations around the world at any time and without prior knowledge of the location of the personal units. This paper provides an overview of the system, the services it provides, its operation, and an overview of the commercial practices and relatively high volume satellite production techniques which will make the system cost effective. A constellation of 66 satellites will provide an orbiting, spherical-shell, infrastructure for this global calling capability. The satellites act as tall cellular towers and allow convenient operation for portable handheld telephones. The system will provide a full range of services including voice, paging, data, geolocation, and fax capabilities. Motorola is a world leader in the production of high volume, high quality, reliable telecommunications hardware. One of Iridium's goals is to apply these production techniques to high reliability space hardware. Concurrent engineering, high performance work teams, advanced manufacturing technologies, and improved assembly and test methods are some of the techniques that will keep the Iridium system cost effective. Mobile, global, flexible personal communications are coming that will allow anyone to call or receive a call from/to anyplace at anytime. The Iridium system will provide communications where none exist today. This connectivity will allow increased information transfer, open new markets for various business endeavors, and in general increase productivity and development.

  14. Interactive video audio system: communication server for INDECT portal

    NASA Astrophysics Data System (ADS)

    Mikulec, Martin; Voznak, Miroslav; Safarik, Jakub; Partila, Pavol; Rozhon, Jan; Mehic, Miralem

    2014-05-01

    The paper deals with presentation of the IVAS system within the 7FP EU INDECT project. The INDECT project aims at developing the tools for enhancing the security of citizens and protecting the confidentiality of recorded and stored information. It is a part of the Seventh Framework Programme of European Union. We participate in INDECT portal and the Interactive Video Audio System (IVAS). This IVAS system provides a communication gateway between police officers working in dispatching centre and police officers in terrain. The officers in dispatching centre have capabilities to obtain information about all online police officers in terrain, they can command officers in terrain via text messages, voice or video calls and they are able to manage multimedia files from CCTV cameras or other sources, which can be interesting for officers in terrain. The police officers in terrain are equipped by smartphones or tablets. Besides common communication, they can reach pictures or videos sent by commander in office and they can respond to the command via text or multimedia messages taken by their devices. Our IVAS system is unique because we are developing it according to the special requirements from the Police of the Czech Republic. The IVAS communication system is designed to use modern Voice over Internet Protocol (VoIP) services. The whole solution is based on open source software including linux and android operating systems. The technical details of our solution are presented in the paper.

  15. Rube Goldberg Salad System: Teaching Systems Theory in Communication

    ERIC Educational Resources Information Center

    Linabary, Jasmine R.; Long, Ziyu; Mouton, Ashton; Rao, Ranjani L.; Buzzanell, Patrice M.

    2016-01-01

    Systems theory has been a staple in organizational communication textbooks since the field's inception (Miller, 2015; Poole, 2014). Nevertheless, the authors' classroom experiences have revealed that systems theory may not seem applicable to students due to its complicated nature. While examples and cases can help students make sense of the…

  16. Design and analysis of the satellite laser communications network

    NASA Astrophysics Data System (ADS)

    Ren, Pei-an; Qian, Fengchen; Liu, Qiang; Jin, Linlin

    2015-02-01

    A satellite laser communications network structure with two layers and multiple domains has been proposed, which performance has been simulated by OPENT. To simulation, we design several OPNET models of the network's components based on a satellite constellation with two layers and multiple domains, as network model, node model, MAC layer protocol and optical antenna model. The network model consists of core layer and access layer. The core network consists of four geostationary orbit (GEO) satellites which are uniformly distributed in the geostationary orbit. The access network consists of 6 low Earth orbit (LEO) satellites which is the walker delta (walk-δ) constellation with three orbit planes. In access layer, each plane has two satellites, and the constellation is stably. The satellite constellation presented for space laser network can meet the demand of coverage in the middle and low latitude by a few satellites. Also several terminal device models such as the space laser transmitter, receiver, protocol layer module and optical antenna have been designed according to the inter-satellite links in different orbits t from GEO to LEO or GEO to ground. The influence to network of different transmitting throughput, receiving throughput, network protocol and average time delay are simulated. Simulation results of network coverage, connectivity and traffic load performance in different scenes show that the satellite laser network presented by the paper can be fit for high-speed satellite communications. Such analysis can provide effective reference for the research of satellite laser networking and communication protocol.

  17. 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.

  18. The Design of the Digital Multiplexer based on Power Carrier Communication on Sports Venues

    NASA Astrophysics Data System (ADS)

    Lu, Ming-jing; Liang, Li; Yu, Xiao-yan

    In this paper, one kind of double CPU, the low power loss, the low cost digital multiplexer has been designed in conducted the full research to this communicated way, which is satisfied the need of the electric power correspondence transmission system, especially in sports venues. This article is elaborated the digital multiplexer's hardware and the software principle of design in detail, carries on the simulation using the monolithic integrated circuit simulator, has achieved the satisfactory effect through the debug.

  19. Photodiodes for ten micrometer laser communication systems

    NASA Technical Reports Server (NTRS)

    Cohen, S. C.

    1972-01-01

    The performance is discussed of 10-micron mercury-cadmiumtelluride and lead-tin-telluride photodiodes in laser heterodyne communication systems. The dependence of detector quantum efficiency, resistance, frequency response, and signal-to-noise ratio on temperature, bias, and local oscillator power are examined. Included in the discussion is an analysis of the feasibility of high temperature operation, and ability of the detector to dissipate power to a heat sink is explored. Some aspects of direct detection response are considered and figures showing flux levels from a blackbody presented.

  20. Antenna technology for advanced mobile communication systems

    NASA Technical Reports Server (NTRS)

    Rammos, Emmanuel; Roederer, Antoine; Rogard, Roger

    1988-01-01

    The onboard antenna front end is the key subsystem conditioning configuration and performance of mobile communication satellites. The objectives of this paper are to demonstrate this key role and to review L-band satellite antenna technology for earth coverage and regional applications. Multibeam arrays are first discussed, then unfurlable and inflatable reflector antennas are described. These technologies are now qualified in Europe for future mobile systems, for which the optimum choice of antenna technology has been found to be the key to efficient use of spectrum and power resources.

  1. Social-Communicative Effects of the Picture Exchange Communication System (PECS) in Autism Spectrum Disorders

    ERIC Educational Resources Information Center

    Lerna, Anna; Esposito, Dalila; Conson, Massimiliano; Russo, Luigi; Massagli, Angelo

    2012-01-01

    Background: The Picture Exchange Communication System (PECS) is a common treatment choice for non-verbal children with autism. However, little empirical evidence is available on the usefulness of PECS in treating social-communication impairments in autism. Aims: To test the effects of PECS on social-communicative skills in children with autism,…

  2. GAS MAIN SENSOR AND COMMUNICATIONS NETWORK SYSTEM

    SciTech Connect

    Hagen Schempf, Ph.D.

    2003-02-27

    Automatika, Inc. was contracted by the Department of Energy (DOE) and with co-funding from the New York Gas Group (NYGAS), to develop an in-pipe natural gas prototype measurement and wireless communications system for assessing and monitoring distribution networks. A prototype system was built for low-pressure cast-iron mains and tested in a spider- and serial-network configuration in a live network in Long Island with the support of Keyspan Energy, Inc. The prototype unit combined sensors capable of monitoring pressure, flow, humidity, temperature and vibration, which were sampled and combined in data-packages in an in-pipe master-slave architecture to collect data from a distributed spider-arrangement, and in a master-repeater-slave configuration in serial or ladder-network arrangements. It was found that the system was capable of performing all data-sampling and collection as expected, yielding interesting results as to flow-dynamics and vibration-detection. Wireless in-pipe communications were shown to be feasible and valuable data was collected in order to determine how to improve on range and data-quality in the future.

  3. An asynchronous communication system based on the hyperchaotic system of 6th-order cellular neural network

    NASA Astrophysics Data System (ADS)

    Wang, Xingyuan; Xu, Bing; Luo, Chao

    2012-11-01

    This paper proposes a novel asynchronous communication scheme. Based on this scheme, a model using the hyperchaotic system of 6th-order Cellular Neural Network (CNN) is designed. This scheme enhances the security of asynchronous communication compared to the conventional ones. It is noteworthy that the proposed communication scheme does not depend on synchronization, and almost all chaotic systems can be involved in this scheme. Numerical simulations show the effectiveness of this scheme.

  4. Remote monitoring system research and implementation based on wireless communication

    NASA Astrophysics Data System (ADS)

    Fu, Weizhi; Meng, Xiaofeng

    2013-03-01

    With rapid development of automatic control and network techniques, network-based remote monitoring is becoming an investigating hotspot in the elevator industry. At the same time as the development of wireless communication technology, remote wireless monitoring technology is applied more and more widely in recent years. A variety of wireless detection equipment is entering various industrial enterprises, and has been widely used. At present, there are many defects of the traditional monitoring system, such as poor real-time, low reliability, low intelligence. Based on the analysis of the difficulties to monitor the mobile terminal, this paper firstly analyzes the GSM/GPRS technology, and then discusses a design of the remote monitoring system based on wireless communication. The architecture of the monitoring center is introduced in detail. It is characterized by user-friendly, easy operate, good real-time and easy to extend.

  5. An Orbiting Standards Platform for communication satellite system RF measurements

    NASA Technical Reports Server (NTRS)

    Wallace, R. G.; Woodruff, J. J.

    1978-01-01

    The Orbiting Standards Platform (OSP) is a proposed satellite dedicated to performing RF measurements on space communications systems. It would consist of a quasi-geostationary spacecraft containing an ensemble of calibrated RF sources and field strength meters operating in several microwave bands, and would be capable of accurately and conveniently measuring critical earth station and satellite RF performance parameters, such as EIRP, gain, figure of merit (G/T), crosspolarization, beamwidth, and sidelobe levels. The feasibility and utility of the OSP concept has been under joint study by NASA, NBS, Comsat and NTIA. A survey of potential OSP users was conducted by NTIA as part of this effort. The response to this survey, along with certain trends in satellite communications system design, indicates a growing need for such a measurement service.

  6. An advanced domestic satellite communications system

    NASA Technical Reports Server (NTRS)

    1980-01-01

    An updated traffic projection for U.S. domestic satellite communications service covering a period of 15 years; mid-1980 to mid-1995 was prepared. This model takes into account expected technology advances and reductions in transmission costs, legislative and regulatory changes permitting increased competition, and rising energy costs which will encourage more extensive substitution of telecommunications for travel. The historical development and current status of satellite systems are discussed as well as the characteristics of follow-on systems. Orbital arc utilization, spacecraft configuration for single shuttle launch, Earth station configuration, and system costs are examined. Areas which require technology development include multiple beam frequency reuse antennas, on-board switching, intersatellite links, and ka-band operation. Packing and deployment schemes for enclosing the satellite within the shuttle orbiter bay must also be devised.

  7. ECS - The European Communication Satellite system

    NASA Astrophysics Data System (ADS)

    Wooster, C. B.

    1981-09-01

    The evolution of the European Communication Satellite system (ECS) is traced from feasibility studies in 1970 to the development and launch in 1978 of the Orbital Test Satellite (OTS) by the European Space Agency to prove the new satellite and radio transmission technology being used on ECS. This was followed by the establishment of 'Interim EUTELSAT' in 1979 as the organization to operate ECS. The satellite, which operates at 11/14 GHz, covers all the capitals in Europe via three spot beam antennas, supplemented by a 'Eurobeam' regional coverage antenna which extends the range to cover all of Europe and the Mediterranean basin. Telephony channels are transmitted digitally using time division multiple access (TDMA) with digital speech interpolation (DSI) to optimize satellite capacity. Television transmission is by analog FM over the Eurobeam antenna to North African as well as European capitals. System implications of TDMA operation are discussed, and the EUTELSAT policy for Special Services or satellite business systems is discussed.

  8. An Ontology-Based Collaborative Design System

    NASA Astrophysics Data System (ADS)

    Su, Tieming; Qiu, Xinpeng; Yu, Yunlong

    A collaborative design system architecture based on ontology is proposed. In the architecture, OWL is used to construct global shared ontology and local ontology; both of them are machine-interpretable. The former provides a semantic basis for the communication among designers so as to make the designers share the common understanding of knowledge. The latter which describes knowledge of designer’s own is the basis of design by reasoning. SWRL rule base comprising rules defined based on local ontology is constructed to enhance the reasoning capability of local knowledge base. The designers can complete collaborative design at a higher level based on the local knowledge base and the global shared ontology, which enhances the intelligence of design. Finally, a collaborative design case is presented and analyzed.

  9. Communication Security for Control Systems in Smart Grid

    NASA Astrophysics Data System (ADS)

    Robles, Rosslin John; Kim, Tai-Hoon

    As an example of Control System, Supervisory Control and Data Acquisition systems can be relatively simple, such as one that monitors environmental conditions of a small office building, or incredibly complex, such as a system that monitors all the activity in a nuclear power plant or the activity of a municipal water system. SCADA systems are basically Process Control Systems, designed to automate systems such as traffic control, power grid management, waste processing etc. Connecting SCADA to the Internet can provide a lot of advantages in terms of control, data viewing and generation. SCADA infrastructures like electricity can also be a part of a Smart Grid. Connecting SCADA to a public network can bring a lot of security issues. To answer the security issues, a SCADA communication security solution is proposed.

  10. Passive monitoring for automated MMPP communication systems

    NASA Astrophysics Data System (ADS)

    Riley, N. G.

    1994-07-01

    A recently completed study of passive sensing techniques for hf communication systems has shown that these sensing techniques can yield data which may be of use in the control of adaptive hf communication systems. The aim of this paper is to review work carried out to date on these techniques and to examine the feasibility of applying similar techniques to radio systems utilizing higher carrier frequencies, up to around 200MHz, where many propagation modes other than ionospheric skywave may exist. Whilst inputs for the control of adaptive radio systems may be derived from a number of sources, many techniques, such as pilot-tone soundings and the transmission of training sequences, involve radiation of signals which may be undesirable in a tactical situation. System control information may also be derived by monitoring other signals which are already present in related parts of the radio spectrum, allowing more covert operation and avoiding unnecessary pollution of the radio spectrum. Derivation of such control information for use in hf systems has been studied in some detail, utilizing the following types of radio signals existing in the hf band: swept frequency sounder signals radiated by other uses of the hf spectrum, broadcast signals, standard time signals, meteorological data signals (RTTY), and overall statistical occupancy measurements of the spectrum. Some of these techniques would also be applicable to the multimechanism case, provided that the more complex propagation inversion, which is due to the greater range of propagation mechanisms available, can be taken into account. Additional, higher frequency, sources of RF energy which may provide data through passive monitoring, include aeronautical navigation beacons, amateur beacons and various types of radar signals. Use may also be made of low-orbiting satellite signals, although these present tracking problems in terms of doppler shift and give data mainly related to ionospheric scintillation and hence

  11. GAS MAIN SENSOR AND COMMUNICATIONS NETWORK SYSTEM

    SciTech Connect

    Hagen Schempf

    2004-09-30

    Automatika, Inc. was contracted by the Department of Energy (DOE) and with co-funding from the New York Gas Group (NYGAS), to develop an in-pipe natural gas prototype measurement and wireless communications system for assessing and monitoring distribution networks. In Phase II of this three-phase program, an improved prototype system was built for low-pressure cast-iron and high-pressure steel (including a no-blow installation system) mains and tested in a serial-network configuration in a live network in Long Island with the support of Keyspan Energy, Inc. The experiment was carried out in several open-hole excavations over a multi-day period. The prototype units (3 total) combined sensors capable of monitoring pressure, flow, humidity, temperature and vibration, which were sampled and combined in data-packages in an in-pipe master-repeater-slave configuration in serial or ladder-network arrangements. It was verified that the system was capable of performing all data-sampling, data-storage and collection as expected, yielding interesting results as to flow-dynamics and vibration-detection. Wireless in-pipe communications were shown to be feasible and the system was demonstrated to run off in-ground battery- and above-ground solar power. The remote datalogger access and storage-card features were demonstrated and used to log and post-process system data. Real-time data-display on an updated Phase-I GUI was used for in-field demonstration and troubleshooting.

  12. Communications

    NASA Technical Reports Server (NTRS)

    Hathorn, S.

    1985-01-01

    An overview of NASA's Thin Route satellite telecommunication project is presented. Thin Route employs applications technology satellites (ATS) in place of more costly commercial multi- transponder telecommunications satellites. This system allows remote and underdeveloped areas to communicate with the outside world for purposes of obtaining medical assistance among other things. The system represents a substantial cost saving over commercial systems.

  13. Depolarization effects on free space laser transceiver communication systems

    NASA Astrophysics Data System (ADS)

    Hoeller, Frank Stefan; Juranek, Hans Joachim

    1990-07-01

    A technique developed at ESTEC for the measurement and theoretical estimation of optical polarization in the antenna telescopes of space optical communication systems (e.g., the ESA SILEX intersatellite system using 825-nm semiconductor lasers) is described. The design methods used to achieve high channel separation ratios in the SILEX telescopes are recalled; the failure of straightforward measurement techniques in practical ground-based testing is explained; and a solution based on the mathematical relationship between far-field and near-field intensity distributions is outlined. The primary instrument used in this method is a scanning ellipsometer.

  14. Inter-Vehicle Communication System Utilizing Autonomous Distributed Transmit Power Control

    NASA Astrophysics Data System (ADS)

    Hamada, Yuji; Sawa, Yoshitsugu; Goto, Yukio; Kumazawa, Hiroyuki

    In ad-hoc network such as inter-vehicle communication (IVC) system, safety applications that vehicles broadcast the information such as car velocity, position and so on periodically are considered. In these applications, if there are many vehicles broadcast data in a communication area, congestion incurs a problem decreasing communication reliability. We propose autonomous distributed transmit power control method to keep high communication reliability. In this method, each vehicle controls its transmit power using feed back control. Furthermore, we design a communication protocol to realize the proposed method, and we evaluate the effectiveness of proposed method using computer simulation.

  15. Design Language for Digital Systems

    NASA Technical Reports Server (NTRS)

    Shiva, S. G.

    1985-01-01

    Digital Systems Design Language (DDL) is convenient hardware description language for developing and testing digital designs and for inputting design details into design automation system. Describes digital systems at gate, register transfer, and combinational block levels. DDL-based programs written in FORTRAN IV for batch execution.

  16. 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.

  17. A communication model for interlinking national tsunami early warning systems

    NASA Astrophysics Data System (ADS)

    Lendholt, M.; Hammitzsch, M.; Esbri Palomares, M. A.

    2012-04-01

    The integration of national Tsunami Early Earning Systems (TEWS) to ocean-wide networks is a main objective of the UNESCO Intergovernmental Oceanic Commission (IOC) tsunami programme. The intention is to interlink national TEWSs leveraging warning communication during hazards. For this purpose a communication model has been developed enabling an efficient message exchange within a centre-to-centre (C2C) communication in a system-of-systems environment. The model, designed to be robust and simple, is based on existing interoperability standards from the Open Geospatial Consortium (OGC) and the Organization of the Advancement of Structured Information Standards (OASIS). For the exchange of tsunami warning bulletins the Common Alerting Protocol (CAP) is used. It supports geospatial referencing by addressing geocoded Points of Interests (POIs), Areas of Interest (AOIs) and Coastal Forecast Zones (CFZs). Moreover it supports hazard classification by standardized criticality parameters and the transmission of attachments, e.g. situation maps. The communication model also supports the exchange of sensor observations and measurements such as sea level data or earthquake parameters. For this purpose markup languages of the Sensor Web Enablement (SWE) suite are used. Both communication products, warning bulletins and sensor observations, are embedded in an envelope providing addressing and routing information using the Emergency Data Exchange Language Distribution Element (EDXL-DE). The communication model has been implemented in a first pilot based on Message Oriented Middleware (MOM). Implementation, test and validation was started in the European research project Distant Early Warning System (DEWS) and is continued successively in the project Collaborative, Complex, and Critical Decision Processes in Evolving Crises (TRIDEC). Stimulated by the concepts and results of the German Indonesian Tsunami Early Warning System (GITEWS) and based on its sensor integration platform

  18. Ultrasonic speech translator and communications system

    DOEpatents

    Akerman, M. Alfred; Ayers, Curtis W.; Haynes, Howard D.

    1996-01-01

    A wireless communication system undetectable by radio frequency methods for converting audio signals, including human voice, to electronic signals in the ultrasonic frequency range, transmitting the ultrasonic signal by way of acoustical pressure waves across a carrier medium, including gases, liquids, or solids, and reconverting the ultrasonic acoustical pressure waves back to the original audio signal. The ultrasonic speech translator and communication system (20) includes an ultrasonic transmitting device (100) and an ultrasonic receiving device (200). The ultrasonic transmitting device (100) accepts as input (115) an audio signal such as human voice input from a microphone (114) or tape deck. The ultrasonic transmitting device (100) frequency modulates an ultrasonic carrier signal with the audio signal producing a frequency modulated ultrasonic carrier signal, which is transmitted via acoustical pressure waves across a carrier medium such as gases, liquids or solids. The ultrasonic receiving device (200) converts the frequency modulated ultrasonic acoustical pressure waves to a frequency modulated electronic signal, demodulates the audio signal from the ultrasonic carrier signal, and conditions the demodulated audio signal to reproduce the original audio signal at its output (250).

  19. Ultrasonic speech translator and communications system

    DOEpatents

    Akerman, M.A.; Ayers, C.W.; Haynes, H.D.

    1996-07-23

    A wireless communication system undetectable by radio frequency methods for converting audio signals, including human voice, to electronic signals in the ultrasonic frequency range, transmitting the ultrasonic signal by way of acoustical pressure waves across a carrier medium, including gases, liquids, or solids, and reconverting the ultrasonic acoustical pressure waves back to the original audio signal. The ultrasonic speech translator and communication system includes an ultrasonic transmitting device and an ultrasonic receiving device. The ultrasonic transmitting device accepts as input an audio signal such as human voice input from a microphone or tape deck. The ultrasonic transmitting device frequency modulates an ultrasonic carrier signal with the audio signal producing a frequency modulated ultrasonic carrier signal, which is transmitted via acoustical pressure waves across a carrier medium such as gases, liquids or solids. The ultrasonic receiving device converts the frequency modulated ultrasonic acoustical pressure waves to a frequency modulated electronic signal, demodulates the audio signal from the ultrasonic carrier signal, and conditions the demodulated audio signal to reproduce the original audio signal at its output. 7 figs.

  20. 14 CFR 1221.108 - Establishment of the NASA Unified Visual Communications System.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... forward-looking image through the use of effective design for improved communications. The system provides... spacecraft markings and other items. It creates a unified image which is representative and symbolic of...