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Sample records for satellite communications service

  1. Public service satellite communications

    NASA Technical Reports Server (NTRS)

    Wolff, E. A.

    1978-01-01

    It is suggested that the high effective isotropic radiated power provided by high-power satellite transmitters and high-gain antennas could be used in conjunction with economical ground receivers to furnish public services in remote areas of the U.S. Applications to health care, education and public safety are mentioned. A system concept involving a communications satellite operating in the Ku-band (12-GHz down, 14-GHz up) and either 100/30 watt stationary earth terminals with 1-1.8 m antennas or mobile terminals with omnidirectional antennas is presented.

  2. Public Service Communication Satellite Program

    NASA Technical Reports Server (NTRS)

    Brown, J. P.

    1977-01-01

    The proposed NASA Public Service Communication Satellite Program consists of four different activities designed to fulfill the needs of public service sector. These are: interaction with the users, experimentation with existing satellites, development of a limited capability satellite for the earliest possible launch, and initiation of an R&D program to develop the greatly increased capability that future systems will require. This paper will discuss NASA efforts in each of these areas.

  3. Satellite communication for public services

    NASA Technical Reports Server (NTRS)

    Cooper, R. S.; Redisch, W. N.

    1977-01-01

    Public service programs using NASA's ATS-6 and CTS satellites are discussed. Examples include the ATS-6 Health and Education Telecommunications experimental program and the use of CTS to enable students in one university to take courses presented at another distant university. Possible applications of satellite communication systems to several areas of public service are described, and economic and political obstacles hindering the implementation of these programs are considered. It is suggested that a federally sponsored program demonstrating the utility of satellites accomodating a large number of small terminals is needed to encourage commercial satellite operations.

  4. A public service communications satellite user brochure

    NASA Technical Reports Server (NTRS)

    1977-01-01

    The capabilities of a proposed communications satellite that would be devoted to experiments and demonstrations of various public services is described. A Public Service Communications Satellite study was undertaken at the NASA Goddard Space Flight Center (GSFC) to define the problems and opportunities of a renewed NASA role and the form such NASA involvement should take. The concept that has evolved has resulted from careful consideration of experiments that were already undertaken on existing satellites.

  5. Communication Satellites: Experimental & Operational, Commercial & Public Service.

    ERIC Educational Resources Information Center

    Development Communication Report, 1979

    1979-01-01

    The title reflects the first and major article in an issue of this newsletter devoted entirely to communication satellites. This series of articles on the potential and applications of communication satellites in development projects is concerned with their development for commercial and public service, development in the Pacific region, SPACECOM…

  6. Public Service Communications Satellite User Requirements Workshop

    NASA Technical Reports Server (NTRS)

    Wolff, E. A.

    1977-01-01

    Information on user requirements for public service communications was acquired to provide the basis of a study to determine the optimum satellite system to satisfy user requirements. The concept for such a system is described: Topics discussed included requirements for data and message services, elementary and secondary education, extension and continuing education, environmental communications, library services, medical education, medical services, public broadcasting, public safety, religious applications, state and local communications, and voluntary services. Information was also obtained on procedures to follow to make the transfer to commercial services.

  7. Servicing communication satellites in geostationary orbit

    NASA Technical Reports Server (NTRS)

    Russell, Paul K.; Price, Kent M.

    1990-01-01

    The econmic benefits of a LEO space station are quantified by identifying alternative operating scenarios utilizing the space station's transportation facilities and assembly and repair facilities. Particular consideration is given to the analysis of the impact of on-orbit assembly and servicing on a typical communications satellite is analyzed. The results of this study show that on-orbit servicing can increase the internal rate of return by as much as 30 percent.

  8. 14/12-GHz-band satellite communication services

    NASA Astrophysics Data System (ADS)

    Hayashi, Kunihiro; Nagaki, Kiyoaki; Mori, Yasuo

    1990-01-01

    Three new systems for integrated TV-relay services have been developed: Satellite Video Comunication Service (SVCS) and Satellite Digital Communication Service (SDCS), with Japan's 14/12-GHz-band commercial communication satellites. These systems have been in commercial use since May 1989. Usually SVCS and SDCS have been provided using Ka-band (30/20 GHz-band) of CS-2 and Cs-3. This paper provides an overview of the design, the performance, and the systems of the new 14/12-GHz-band satellite communication services.

  9. USDA Forest Service mobile satellite communications applications

    NASA Technical Reports Server (NTRS)

    Warren, John R.

    1990-01-01

    The airborne IR signal processing system being developed will require the use of mobile satellite communications to achieve its full capability and improvement in delivery timeliness of processed IR data to the Fire Staff. There are numerous other beneficial uses, both during wildland fire management operations or in daily routine tasks, which will also benefit from the availability of reliable communications from remote areas.

  10. Mobile satellite service communications tests using a NASA satellite

    NASA Technical Reports Server (NTRS)

    Chambers, Katherine H.; Koschmeder, Louis A.; Hollansworth, James E.; ONeill, Jack; Jones, Robert E.; Gibbons, Richard C.

    1995-01-01

    Emerging applications of commercial mobile satellite communications include satellite delivery of compact disc (CD) quality radio to car drivers who can select their favorite programming as they drive any distance; transmission of current air traffic data to aircraft; and handheld communication of data and images from any remote corner of the world. Experiments with the enabling technologies and tests and demonstrations of these concepts are being conducted before the first satellite is launched by utilizing an existing NASA spacecraft.

  11. Satellite communications for the next generation telecommunication services and networks

    NASA Technical Reports Server (NTRS)

    Chitre, D. M.

    1991-01-01

    Satellite communications can play an important role in provisioning the next-generation telecommunication services and networks, provided the protocols specifying these services and networks are satellite-compatible and the satellite subnetworks, consisting of earth stations interconnected by the processor and the switch on board the satellite, interwork effectively with the terrestrial networks. The specific parameters and procedures of frame relay and broadband integrated services digital network (B-ISDN) protocols which are impacted by a satellite delay. Congestion and resource management functions for frame relay and B-ISDN are discussed in detail, describing the division of these functions between earth stations and on board the satellite. Specific onboard and ground functions are identified as potential candidates for their implementation via neural network technology.

  12. Satellite Communication.

    ERIC Educational Resources Information Center

    Technology Teacher, 1985

    1985-01-01

    Presents a discussion of communication satellites: explains the principles of satellite communication, describes examples of how governments and industries are currently applying communication satellites, analyzes issues confronting satellite communication, links mathematics and science to the study of satellite communication, and applies…

  13. Emerging markets for satellite data communications in the public service

    NASA Technical Reports Server (NTRS)

    Potter, J. G.

    1978-01-01

    The paper discusses some of the current and potential markets for satellite data communications as projected by the Public Service Satellite Consortium (PSSC). Organizations in the public service sector are divided into three categories, depending on their expected benefits and organizational changes due to increased satellite telecommunications use: A - modest institutional adjustments are necessary and significant productivity gains are likely; B - institutional requirements picture is promising, but more information is needed to assess benefits and risk; and C - major institutional adjustments are needed, risks are high but possible benefits are high. These criteria are applied to the U.S. health care system, continuing education, equipment maintenance, libraries, environmental monitoring, and other potential markets. The potential revenues are seen to be significant, but what is needed is a cooperative effort by common carriers and major public service institutions to aggregate the market.

  14. Planning satellite communication services and spectrum-orbit utilization

    NASA Technical Reports Server (NTRS)

    Sawitz, P. H.

    1982-01-01

    The relationship between approaches to planning satellite communication services and spectrum-orbit utilization is considered, with emphasis on the fixed-satellite and the broadcasting-satellite services. It is noted that there are several possible approaches to planning space services, differing principally in the rigidity with which technical parameters are prescribed, in the time for which a plan remains in force, and in the procedures adopted for implementation and modifications. With some planning approaches, spectrum-orbit utilization is fixed at the time the plan is made. Others provide for greater flexibility by making it possible to postpone some decisions on technical parameters. In addition, the two political questions of what is equitable access and how it can be guaranteed in practice play an important role.

  15. Repeater in the sky. [public service communications satellite program

    NASA Technical Reports Server (NTRS)

    Cote, C. E.; Brown, J. P.

    1977-01-01

    The Public Service Communications Satellite (PSCS) program is intended to develop and demonstrate a space system aimed at stimulating future commercial markets in fixed and mobile applications. The services are envisioned for rural areas, regions beyond access to terrestrial systems, or for continuous cross-country applications. The system incorporates a UHF repeater for mobile voice and data experiments; 8 MHz of spectrum is specified for serving 70 channels. This paper describes the PSCS program and discusses some demonstration experiments. A future concept based on large structure multibeam antennas is also discussed.

  16. Developing satellite communications for public service: Prospects in four service areas

    NASA Technical Reports Server (NTRS)

    1977-01-01

    The Public Service Satellite Consortium evaluated prospects for satellite telecommunications in four areas of the public service: the U.S. health care system, elementary and secondary education, American libraries, and that sector of the public service which is concerned with the provision of continuing education to health professionals. Three important conclusions were reached. First, throughout the public service there are three recurring needs: improved access, cost containment, and maintenance of quality. Appropriate application of communication satellite systems could ameliorate each of these concerns. Second, there appears to be an enormous latent demand for data communication services throughout the public service. The potential demand in 1982 to support requirements in hospital administration, library services and other information-retrieval activities, equipment maintenance, and environmental monitoring may be in excess of $300 million a year. Third, administrative applications of data communication networks show particular promise, especially in rural areas.

  17. Estimation of the demand for public services communications. [market research and economic analysis for a communications satellite system

    NASA Technical Reports Server (NTRS)

    1976-01-01

    Market analyses and economic studies are presented to support NASA planning for a communications satellite system to provide public services in health, education, mobile communications, data transfer, and teleconferencing.

  18. Public service communications satellite. [health, education, safety and information transfer applications

    NASA Technical Reports Server (NTRS)

    Wolff, E. A.

    1978-01-01

    Health, education, public safety, and information transfer applications of public service communications satellites are discussed with particular attention to the use of communications satellites to improve rural health delivery. Health-care communications requirements are summarized. The communications system concept involves small inexpensive stationary, portable, and moving ground terminals which will provide communications between any two points in the U.S. with both fixed and moving terminals on a continuous 24-hour basis. User requirements, wavebands, and privacy techniques are surveyed.

  19. Satellite provided fixed communications services: A forecast of potential domestic demand through the year 2000: Volume 2: Main text

    NASA Technical Reports Server (NTRS)

    Kratochvil, D.; Bowyer, J.; Bhushan, C.; Steinnagel, K.; Kaushal, D.; Al-Kinani, G.

    1983-01-01

    Potential satellite-provided fixed communications services, baseline forecasts, net long haul forecasts, cost analysis, net addressable forecasts, capacity requirements, and satellite system market development are considered.

  20. Satellite communications experiment for the Ontario air ambulance service

    NASA Technical Reports Server (NTRS)

    Butterworth, John S.

    1988-01-01

    A satellite communications experiment was conducted to develop a reliable voice communications system between paramedics and doctors at certain larger medical centers. The experiment used INMARSAT's Atlantic Ocean Region satellite which provides coverage to the western border of Ontario. Forward downlink power from the satellite is in great demand, so two highly power-efficient modulation schemes were chosen for evaluation during the experiment. These were amplitude-companded single-sideband (ACSSB) and linear predictive coding in conjunction with DMSK modulation. Good performance with a signal to noise ratio of about 10 dB was demonstrated from many parts of the province with the evevation angle to the satellite ranging from five to twenty degrees and with the aircraft both in-flight and on the runway.

  1. Satellite applications to electric-utility communications needs. [land mobile satellite service

    NASA Technical Reports Server (NTRS)

    Horstein, M.; Barnett, R.

    1981-01-01

    Significant changes in the Nation's electric power systems are expected to result from the integration of new technology, possible during the next decade. Digital communications for monitor and control, exclusive of protective relaying, are expected to double or triple current traffic. A nationwide estimate of 13 Mb/s traffic is projected. Of this total, 8 Mb/s is attributed to the bulk-power system as it is now being operated (4 Mb/s). This traffic could be accommodated by current communications satellites using 3- to 4.5-m-diameter ground terminals costing $35,000 to $70,000 each. The remaining 5-Mb/s traffic is attributed to new technology concepts integrated into the distribution system. Such traffic is not compatible with current satellite technology because it requires small, low-cost ground terminals. Therefore, a high effective isotropic radiated power satellite, such as the one being planned by NASA for the Land Mobile Satellite Service, is required.

  2. The application of mobile satellite services to emergency response communications

    NASA Technical Reports Server (NTRS)

    Freibaum, J.

    1980-01-01

    The application of an integrated satellite/terrestrial emergency response communications system in disaster relief operations is discussed. Large area coverage communications capability, full-time availability, a high degree of mobility, plus reliability, are pointed out as criteria for an effective emergency communications system. Response time is seen as a major factor determining the possible survival and/or protection of property. These criteria, can not be met by existing communications systems and complete blackouts were experienced during the past decades caused by either interruption or destruction of existing power lines, and overload or inadequacy of remaining lines. Several emergency cases, caused by either hurricanes, tornados, or floods, during which communication via satellite was instrumental to inform rescue and relief teams, are described in detail. Seismic Risk Maps and charts of Major Tectonic Plates Earthquake Epicenters are given, and it is noted that, 35 percent of the U.S. population is living in critical areas. National and international agreements for the implementation of a satellite-aided global Search and Rescue Program is mentioned. Technological and economic breakthroughs are still needed in large multibeam antennas, switching circuits, and low cost mobile ground terminals. A pending plan of NASA to initiate a multiservice program in 1982/83, with a Land Mobile Satellite capability operating in the 806 - 890 MHz band as a major element, may help to accelerate the needed breakthroughs.

  3. Provision of Electronic Healthcare Services via DVB-RCS Satellite Communication Technology

    E-print Network

    Vouyioukas, Demosthenes

    Provision of Electronic Healthcare Services via DVB-RCS Satellite Communication Technology V of Information and Communication Systems Engineering, University of the Aegean, Karlovasi 83200, Samos, Greece, e-mail: dvouyiou@aegean.gr Abstract The advent of broadband communications technologies has paved the way

  4. Use of communications. [satellite communication

    NASA Technical Reports Server (NTRS)

    1975-01-01

    Progress in the field of satellite communications is reviewed, and useful services which may be provided by future satellite communications systems are considered. Recommendations are made with regard to mobile communications for use on land and at sea, position determination, mineral and energy exploration, the possibility of using electronic means to assist in main delivery, education and health-care experiments, and the use of satellite telecommunications to enhance the quality of life in rural areas by making available a full range of educational and entertainment programs. The needs of the amateur radio community are also considered.

  5. Preliminary benefits study for a public service communications satellite system: Task order 2

    NASA Technical Reports Server (NTRS)

    1978-01-01

    The economic and social benefits to accrue from an operational public service communications satellite system are estimated for the following applications: teleradiology, emergency medical services, teleconferencing for both civilian and defense agencies, data transfer, remote cardiac monitoring, teleconsultation, continuing education for professionals, and severe storm warning. The potential impact of improved communication on the cost and quality of services are assessed for various agencies, professions, and industries.

  6. Remarks by Dr. James C. Fletcher at Conference on Satellite Communication and Public Service

    NASA Technical Reports Server (NTRS)

    Fletcher, J. C.

    1976-01-01

    The present status of communications satellites, together with the future goals and technology developments in use of public service, is assessed. Improvements in design during the last decade considerably cut the cost of their development and launching, and the systems carry information to millions of people on earth. The space shuttles will change the rules in design and make it possible for communications satellites to have multiple frequencies operating at high power.

  7. 78 FR 14952 - Earth Stations Aboard Aircraft Communicating with Fixed-Satellite Service Geostationary-Orbit...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-03-08

    ...Fixed-Satellite Service Geostationary-Orbit Space Stations AGENCY: Federal Communications...be authorized to communicate with GSO space stations of the FSS on a primary basis in the 11.7-12.2 GHz band (space-to-Earth), on an unprotected...

  8. Satellite Services for Internet Access in Rural Areas1 McClure School of Communication Systems Management

    E-print Network

    Kruse, Hans

    Satellite Services for Internet Access in Rural Areas1 Hans Kruse McClure School of Communication of direct satellite services for internet access in rural areas. The broad success of direct to home provided an incentive for service providers to put together satellite internet access packages. At the same

  9. Optimization of orbital assignment and specification of service areas in satellite communications

    NASA Technical Reports Server (NTRS)

    Wang, Cou-Way; Levis, Curt A.; Buyukdura, O. Merih

    1987-01-01

    The mathematical nature of the orbital and frequency assignment problem for communications satellites is explored, and it is shown that choosing the correct permutations of the orbit locations and frequency assignments is an important step in arriving at values which satisfy the signal-quality requirements. Two methods are proposed to achieve better spectrum/orbit utilization. The first, called the delta S concept, leads to orbital assignment solutions via either mixed-integer or restricted basis entry linear programming techniques; the method guarantees good single-entry carrier-to-interference ratio results. In the second, a basis for specifying service areas is proposed for the Fixed Satellite Service. It is suggested that service areas should be specified according to the communications-demand density in conjunction with the delta S concept in order to enable the system planner to specify more satellites and provide more communications supply.

  10. Satellite Communications for ATM

    NASA Technical Reports Server (NTRS)

    Shamma, Mohammed A.

    2003-01-01

    This presentation is an overview on Satellite Communication for the Aeronautical Telecommunication Management (ATM) research. Satellite Communications are being considered by the FAA and NASA as a possible alternative to the present and future ground systems supporting Air Traffic Communications. The international Civil Aviation Organization (ICAO) have in place Standards and Recommended Practices (SARPS) for the Aeronautical Mobile Satellite Services (AMSS) which is mainly derived from the pre-existing Inmarsat service that has been in service since the 1980s. The Working Group A of the Aeronautical Mobile Communication Panel of ICAO has also been investigating SARPS for what is called the Next Generation Satellite Service (NGSS) which conforms less to the Inmarsat based architecture and explores wider options in terms of satellite architectures. Several designs are being proposed by Firms such as Boeing, ESA, NASA that are geared toward full or secondary usage of satellite communications for ATM. Satellite communications for ATM can serve several purposes ranging from primary usage where ground services would play a minimal backup role, to an integrated solution where it will be used to cover services, or areas that are less likely to be supported by the proposed and existing ground infrastructure. Such Integrated roles can include usage of satellite communications for oceanic and remote land areas for example. It also can include relieving the capacity of the ground network by providing broadcast based services of Traffic Information Services messages (TIS-B), or Flight Information Services (FIS-B) which can take a significant portion of the ground system capacity. Additionally, satellite communication can play a backup role to support any needs for ground replacement, or additional needed capacity even after the new digital systems are in place. The additional bandwidth that can be provided via satellite communications can also open the door for many new applications that generally will enhance the standard services provided. All of those possibilities were investigated and comments, as well as descriptions of those analyses are put forward, as well as suggestions for future areas of study.

  11. 78 FR 14952 - Earth Stations Aboard Aircraft Communicating with Fixed-Satellite Service Geostationary-Orbit...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-03-08

    ... Electronic Comment Filing System (ECFS). See Electronic Filing of Documents in Rulemaking Proceedings, 63 FR... COMMISSION 47 CFR Part 2 Earth Stations Aboard Aircraft Communicating with Fixed-Satellite Service... of Earth Stations Aboard Aircraft (ESAA) in the 14.0-14.5 GHz band from secondary to primary...

  12. 78 FR 19172 - Earth Stations Aboard Aircraft Communicating with Fixed-Satellite Service Geostationary-Orbit...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-03-29

    ..., FR Doc. 2013-04429, on page 14952, column 1, correct the DATES section to read as follows: DATES... COMMISSION 47 CFR Parts 2 and 25 Earth Stations Aboard Aircraft Communicating with Fixed-Satellite Service... proposed rule that appeared in the Federal Register of March 8, 2013. The document proposed rules for...

  13. Communication satellite studies applicable to mobile telephone services

    NASA Technical Reports Server (NTRS)

    Anderson, R. E.; Milton, R. T.; Brown, J. P.

    1979-01-01

    The potential use of satellites as extensions of existing terrestrial land mobile systems is discussed. Compatibility, particularly with cellular type systems, is considered. Sample technical and cost parameters and market assessments are also presented.

  14. Evolution of the NOAA National Weather Service Satellite Broadcast Network (SBN) to Europe's DVB-S satellite communications technology standard

    NASA Astrophysics Data System (ADS)

    Cragg, Phil; Brockman, William E.

    2006-08-01

    The National Oceanic and Atmospheric Administration's (NOAA) National Weather Service (NWS) uses a commercial Satellite Broadcast Network (SBN) to distribute weather data to the NWS AWIPS workstations and National Centers and to NWS Family of Service Users. Advances in science and technology from NOAA's observing systems, such as remote sensing satellites and NEXRAD radars, and advances in Numeric Weather Prediction have greatly increased the volume of data to be transmitted via the SBN. The NOAA-NWS SBN Evolution Program did a trade study resulting in the selection of Europe's DVB-S communication protocol as the basis for enabling a significant increase in the SBN capacity. The Digital Video Broadcast (DVB) group, started to develop digital TV for Europe through satellite broadcasting, has become the current standard for defining technology for satellite broadcasting of digital data for much of the world. NOAA-NWS implemented the DVB-S with inexpensive, Commercial Off The Shelf receiving equipment. The modernized NOAA-NWS SBN meets current performance goals and provides the basis for continued future expansion with no increase in current communication costs. This paper discusses aspects of the NOAA-NWS decision and the migration to the DVB-S standard for its commercial satellite broadcasts of observations and Numerical Weather Prediction data.

  15. 47 CFR 25.279 - Inter-satellite service.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ...Section 25.279 Telecommunication FEDERAL COMMUNICATIONS COMMISSION (CONTINUED) COMMON CARRIER SERVICES SATELLITE COMMUNICATIONS Technical Operations § 25.279 Inter-satellite service. (a) Any satellite...

  16. 47 CFR 25.279 - Inter-satellite service.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ...Section 25.279 Telecommunication FEDERAL COMMUNICATIONS COMMISSION (CONTINUED) COMMON CARRIER SERVICES SATELLITE COMMUNICATIONS Technical Operations § 25.279 Inter-satellite service. (a) Any satellite...

  17. 47 CFR 25.279 - Inter-satellite service.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ...Section 25.279 Telecommunication FEDERAL COMMUNICATIONS COMMISSION (CONTINUED) COMMON CARRIER SERVICES SATELLITE COMMUNICATIONS Technical Operations § 25.279 Inter-satellite service. (a) Any satellite...

  18. 47 CFR 25.279 - Inter-satellite service.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ...Section 25.279 Telecommunication FEDERAL COMMUNICATIONS COMMISSION (CONTINUED) COMMON CARRIER SERVICES SATELLITE COMMUNICATIONS Technical Operations § 25.279 Inter-satellite service. (a) Any satellite...

  19. An approach to effective UHF (S/L band) data communications for satellite Personal Communication Service (PCS)

    NASA Technical Reports Server (NTRS)

    Hayase, Joshua Y.

    1995-01-01

    Reliable signaling information transfer is fundamental in supporting the needs of data communication PCS via LMS (Land Mobile Service) SSs (satellite systems). The needs of the system designer can be satisfied only through the collection of media information that can be brought to bear on the pertinent design issues. We at ISI hope to continue our dialogue with fading media experts to address the unique data communications needs of PCS via LMS SSs.

  20. The LEASAT communication satellite

    NASA Astrophysics Data System (ADS)

    Dutcher, G. L.; Eakins, T. C.; Rubin, C. P.

    Communication services will be provided to the U.S. Navy by a series of UHF communications satellites known as LEASAT. The communications payload will be carried on a new spacecraft developed as an optimum bus for Space Shuttle launches; the program is the first of its kind to take advantage of the full 4.6 m Shuttle payload bay diameter. The communications payload incorporates transponders in the UHF and SHF regimes. Four distinct types of transponders are employed: wideband, narrowband, relay, and fleet broadcast. The functional characteristics of each type is described in detail.

  1. Study of spread spectrum multiple access systems for satellite communications with overlay on current services

    NASA Technical Reports Server (NTRS)

    Ha, Tri T.; Pratt, Timothy

    1989-01-01

    The feasibility of using spread spectrum techniques to provide a low-cost multiple access system for a very large number of low data terminals was investigated. Two applications of spread spectrum technology to very small aperture terminal (VSAT) satellite communication networks are presented. Two spread spectrum multiple access systems which use a form of noncoherent M-ary FSK (MFSK) as the primary modulation are described and the throughput analyzed. The analysis considers such factors as satellite power constraints and adjacent satellite interference. Also considered is the effect of on-board processing on the multiple access efficiency and the feasibility of overlaying low data rate spread spectrum signals on existing satellite traffic as a form of frequency reuse is investigated. The use of chirp is examined for spread spectrum communications. In a chirp communication system, each data bit is converted into one or more up or down sweeps of frequency, which spread the RF energy across a broad range of frequencies. Several different forms of chirp communication systems are considered, and a multiple-chirp coded system is proposed for overlay service. The mutual interference problem is examined in detail and a performance analysis undertaken for the case of a chirp data channel overlaid on a video channel.

  2. The plan for the economic evaluation of the public service communication satellite system

    NASA Technical Reports Server (NTRS)

    1977-01-01

    A plan for the economic evaluation of the Public Service Communications Satellite (PSCS) within domestic markets is presented. It extends through the planning, performance and evaluation of economic experiments following the launch of the PSCS in 1982, and includes the consideration of how the results of these experiments impact the transfer from demonstration to operations. The implementation of this plan will provide information needed to understand and manage the economic and social impacts of the PSCS program.

  3. The plan for the economic evaluation of the Public Service Communication Satellite system

    NASA Technical Reports Server (NTRS)

    1977-01-01

    A total plan for the economic evaluation of the PSCS public service communication satellite program within domestic markets is presented. It extends from the present through the planning, performance and evaluation of economic experiments following the launch of the PSCS, and includes the consideration of how the results of these experiments impact the transfer from demonstration to operations. The implementation of this plan will provide NASA with information needed to understand and manage the economic and social impacts of the PSCS program.

  4. Telelibrary: Library Services via Satellite.

    ERIC Educational Resources Information Center

    Liu, Rosa

    1979-01-01

    Investigates the provision of library services via satellite, explains briefly the operation and advantages of communication satellites, and discusses the various telecommunications equipment and services which, when coupled with satellite transmission, will enhance library activities. Demand trend projections for telecommunications services

  5. Wide-area technologies and services in the Trans-Pacific High Data Rate (HDR) satellite communications experiments

    NASA Technical Reports Server (NTRS)

    Hsu, E.; Hung, C.; Kadowaki, N.; Yoshimura, N.; Takahashi, T.; Shopbell, P.; Walker, G.; Wellnitz, D.; Gary, P.; Clark, G.; Yoshikawa, M.; desJardins, R.; Gill, M.; Tatsumi, H.

    2000-01-01

    This paper describes the technologies and services used in the experiments and demonstrations using the Trans-Pacific high data rate satellite communications infrastructure, and how the environment tasked protocol adaptability, scalability, efficiency, interoperability, and robustness.

  6. Navy satellite communications

    NASA Astrophysics Data System (ADS)

    Clair, William C.

    1992-03-01

    The history, current status, and future plans of Navy satellite communications are reviewed. Particular attention is given to Fleet Satellites; the Defense Satellite Communications System; the International Maritime Satellite; Core Command and Control (Core C2), General Purpose Communications, and Navy EHF SATCOM program; and the Copernicus architecture.

  7. Communications satellites - The experimental years

    NASA Technical Reports Server (NTRS)

    Edelson, B. I.

    1983-01-01

    Only eight years after the launc of Sputnik-1 by the Soviet Union, the first commercial satellite, 'Early Bird', entered service. In just twelve years commercial satellite service extended around the earth and became profitable. The reasons for the successful development of the communications satellite services in a comparatively short time are considered. These reasons are related to the presence of three ingredients, taking into account technology to create the system, communications requirements to form a market, and a management structure to implement the system. The formation of the concept of using earth orbiting satellites for telecommunications is discussed. It is pointed out that the years from 1958 to 1964 were the true 'experimental years' for satellite communications. The rapid development of technology during this crucial period is described, giving attention to passive satellites, active systems, and development satellites.

  8. 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.

  9. Communications technology satellite

    NASA Technical Reports Server (NTRS)

    1976-01-01

    A description of the Communications Technology Satellite (CTS), its planned orbit, its experiments, and associated ground facilities was given. The communication experiments, to be carried out by a variety of groups in both the United States and Canada, include tele-education, tele-medicine, community interaction, data communications and broadcasting. A historical summary of communications satellite development was also included.

  10. China's satellite communications discussed

    NASA Astrophysics Data System (ADS)

    Ruhou, Z.

    1986-04-01

    In 1972, China began to enter the age of satellite comunications, and it was realized that satellites could play a large role in television transmission in China. The experimental broadcasting of satellite television programs was begun in 1978, and satisfactory results were obtained. The success of the television transmission demonstration has led to important decisions regarding development of a domestic satellite communications system. Before specialized communications satellites are launched, the decision was made to lease an international communications satellite transmitter. The responsibility of the ground stations were discussed.

  11. Advanced Communications Technology Satellite (ACTS)

    NASA Technical Reports Server (NTRS)

    Gedney, Richard T.; Schertler, Ronald J.

    1989-01-01

    The NASA Advanced Communications Technology Satellite (ACTS) was conceived to help maintain U.S. leadership in the world's communications-satellite market. This experimental satellite is expected to be launched by NASA in 1992 and to furnish the technology necessary for establishing very small aperture terminal digital networks which provide on-demand full-mesh connectivity, and 1.544-MBPS services with only a single hop. Utilizing on-board switching and processing, each individual voice or data circuit can be separately routed to any location in the network. This paper provides an overview of the ACTS and discusses the value of the technology for future communications systems.

  12. NTT domestic satellite communications system

    NASA Astrophysics Data System (ADS)

    Suzuki, R.; Hayashizaki, H.

    1984-10-01

    The NTT domestic satellite communications system is described, and its state of operation is discussed based on commercial service experience. The major parameters of the system and system satellites are given, and the transmission circuits between regional centers and between remote islands and the mainland are shown. The characteristics of the NTT earth stations are presented. Performance data are given to show the effect of rain attenuation and of sun transit on the satellite circuits.

  13. 47 CFR 25.279 - Inter-satellite service.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 2010-10-01 false Inter-satellite service. 25.279 Section 25...CONTINUED) COMMON CARRIER SERVICES SATELLITE COMMUNICATIONS Technical Operations § 25.279 Inter-satellite service. (a) Any satellite...

  14. Mobile communications using satellite

    NASA Astrophysics Data System (ADS)

    Farrell, Jerald F.; Agnew, Carson E.

    The development of mobile satellite service (MSS) is examined. MSS is to provide two-way voice and data communications services to users in low population density areas and who require wide area coverage. The need for MSS is discussed and various examples of the services it would provide are presented. The allocation of frequencies (UHF frequencies) and international issues affecting the creation of MSS are analyzed. Consideration is given to the demand assignment multiple access network control, a digital system for mobile units, amplitude companded, single sideband modulation, and mobile unit antennas for the ground portions of MSS. The use of a scanning beam system to achieve high output over a wide coverage area for the space segment, the linearity and efficiency of the output power amplfiers, and antenna size are studied. The six steps for calling with the MSS are diagramatically given.

  15. 47 CFR 25.225 - Geographic Service Requirements for 17/24 GHz Broadcasting Satellite Service.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ...Requirements for 17/24 GHz Broadcasting Satellite Service. 25.225 Section 25.225 Telecommunication FEDERAL COMMUNICATIONS COMMISSION (CONTINUED) COMMON CARRIER SERVICES SATELLITE COMMUNICATIONS Technical Standards §...

  16. 47 CFR 25.225 - Geographic Service Requirements for 17/24 GHz Broadcasting Satellite Service.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ...Requirements for 17/24 GHz Broadcasting Satellite Service. 25.225 Section 25.225 Telecommunication FEDERAL COMMUNICATIONS COMMISSION (CONTINUED) COMMON CARRIER SERVICES SATELLITE COMMUNICATIONS Technical Standards §...

  17. 47 CFR 25.225 - Geographic Service Requirements for 17/24 GHz Broadcasting Satellite Service.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ...Requirements for 17/24 GHz Broadcasting Satellite Service. 25.225 Section 25.225 Telecommunication FEDERAL COMMUNICATIONS COMMISSION (CONTINUED) COMMON CARRIER SERVICES SATELLITE COMMUNICATIONS Technical Standards §...

  18. 47 CFR 25.225 - Geographic Service Requirements for 17/24 GHz Broadcasting Satellite Service.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ...Requirements for 17/24 GHz Broadcasting Satellite Service. 25.225 Section 25.225 Telecommunication FEDERAL COMMUNICATIONS COMMISSION (CONTINUED) COMMON CARRIER SERVICES SATELLITE COMMUNICATIONS Technical Standards §...

  19. Communication satellites in Canada

    NASA Astrophysics Data System (ADS)

    Palmer, J. D.

    A brief history of the Canadian involvement with domestic communications satellites is presented. Canada is the first country to deploy, through Telesat Canada, a geostationary domestic satellite system. This system, ANIK-A, operates within the 6/4 GHz band, and provides both telephony and television distribution. The limitations of the 6/4 GHz band prompted the Canadian government to join NASA and ESA in the design and construction of an experimental satellite operating in the 14/12 GHz band. The resulting spacecraft (CTS/HERMES) was used in 36 different Canadian Communications experiments. The experiments included were: telemedicine; teleeducation; community communications; administration; and satellite television broadcasting.

  20. 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.

  1. Experiment In Aeronautical-Mobile/Satellite Communication

    NASA Technical Reports Server (NTRS)

    Jedrey, Thomas C.; Lay, Norman E.; Dessouky, Khaled

    1992-01-01

    Report describes study of performance of digital mobile/satellite communication terminals of advanced design intended for use in ground stations and airplanes in aeronautical-mobile service. Study was collaboration of NASA, Federal Aviation Administration (FAA), Communications Satellite Corp. (COMSAT), and International Maritime Satellite System (INMARSAT).

  2. Multi-service satellite communication system based on TDMA demand assignment control

    NASA Astrophysics Data System (ADS)

    Iisaku, S.-I.; Matsuo, K.; Ono, K.

    The design concept and architecture of an Integrated Circuit/Packet Switching System based on Demand Assignment Control (ISSDA), offering integrated services via the TDMA satellite link, are described. Modifications to the No. 7 signalling system for the satellite operation are proposed. The relation between ISSDA and ISDN is discussed, and future plans for system extension are addressed.

  3. Domestic Communications Satellites.

    ERIC Educational Resources Information Center

    Network Project Notebook, 1972

    1972-01-01

    The June, 1972 Federal Communications Commission's (FCC) decision allowed an "open skies" policy in regard to domestic communication satellites and raised Liberal opposition to a situation where exclusive and unchecked communications power is now in the hands of private entrepreneurs, primarily the big Defense Department oriented aerospace…

  4. Satellite-Based Educational Services. Technical Memorandum.

    ERIC Educational Resources Information Center

    Operations Research, Inc., Silver Spring, MD.

    This memorandum contains engineering information relevant to the use of communication satellites for educational purposes. Information is provided for ground terminals as well as satellites. Satellite related issues addressed include: (1) expected life of service of various satellites, (2) constraints on the availability of the satellites, (3)…

  5. Domestic Communication Satellites

    ERIC Educational Resources Information Center

    Horowitz, Andrew

    1974-01-01

    A discussion of the Federal Communications Commission's new policy on domestic satellites in light of our 1) military and economic history; 2) corporate interests; 3) citizen surveillance; and 4) media control. (HB)

  6. Signals from Communications Satellites.

    ERIC Educational Resources Information Center

    Thomsen, Volker

    1996-01-01

    Discusses the Doppler effect for relative motion between a source of waves and an observer and the orbital dynamics of communications satellites. Presents preliminary calculations of the satellite's altitude and linear velocity using only the concepts of the Doppler shift and the mechanics of motion in a circular path. (JRH)

  7. Millimeter wave communication satellite concepts

    NASA Technical Reports Server (NTRS)

    Holland, L. D.; Hilsen, N. B.; Wallace, R. W.; Stevens, G.

    1978-01-01

    Methodology has been developed for identifying viable and appropriate technologies for future NASA millimeter wave research as based upon the technical requirements of potential space communication services. Applicability of the methodology has been verified through its use with two conceptual communications systems. The subsystem cost and weight models are the appropriate level of detail for this study. Application of the methodology to the detailed design of a satellite system would require further model refinement.

  8. 78 FR 19172 - Earth Stations Aboard Aircraft Communicating with Fixed-Satellite Service Geostationary-Orbit...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-03-29

    ...CFR Parts 2 and 25 [IB Docket No. 12-376; FCC 12-161] Earth Stations Aboard Aircraft Communicating with Fixed-Satellite...Register of March 8, 2013. The document proposed rules for Earth Stations Aboard Aircraft. FOR FURTHER INFORMATION...

  9. Experimental Satellite Quantum Communications

    E-print Network

    Giuseppe Vallone; Davide Bacco; Daniele Dequal; Simone Gaiarin; Vincenza Luceri; Giuseppe Bianco; Paolo Villoresi

    2014-06-16

    Quantum Communications on planetary scale require complementary channels including ground and satellite links. The former have progressed up to commercial stage using fiber-cables, while for satellite links, the absence of terminals in orbit has impaired theirs development. However, the demonstration of the feasibility of such links is crucial for designing space payloads and to eventually enable the realization of protocols such as quantum-key-distribution (QKD) and quantum teleportation along satellite-to-ground or intersatellite links. We demonstrated the faithful transmission of qubits from space to ground by exploiting satellite corner cube retroreflectors acting as transmitter in orbit, obtaining a low error rate suitable for QKD. We also propose a two-way QKD protocol exploiting modulated retroreflectors that necessitates a minimal payload on satellite, thus facilitating the expansion of Space Quantum Communications.

  10. Satellite Communications Using Commercial Protocols

    NASA Technical Reports Server (NTRS)

    Ivancic, William D.; Griner, James H.; Dimond, Robert; Frantz, Brian D.; Kachmar, Brian; Shell, Dan

    2000-01-01

    NASA Glenn Research Center has been working with industry, academia, and other government agencies in assessing commercial communications protocols for satellite and space-based applications. In addition, NASA Glenn has been developing and advocating new satellite-friendly modifications to existing communications protocol standards. This paper summarizes recent research into the applicability of various commercial standard protocols for use over satellite and space- based communications networks as well as expectations for future protocol development. It serves as a reference point from which the detailed work can be readily accessed. Areas that will be addressed include asynchronous-transfer-mode quality of service; completed and ongoing work of the Internet Engineering Task Force; data-link-layer protocol development for unidirectional link routing; and protocols for aeronautical applications, including mobile Internet protocol routing for wireless/mobile hosts and the aeronautical telecommunications network protocol.

  11. 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.

  12. 47 CFR 25.279 - Inter-satellite service.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 47 Telecommunication 2 2011-10-01 2011-10-01 false Inter-satellite service. 25.279 Section 25.279 Telecommunication FEDERAL COMMUNICATIONS COMMISSION (CONTINUED) COMMON CARRIER SERVICES SATELLITE COMMUNICATIONS Technical Operations § 25.279 Inter-satellite service. (a) Any satellite communicating with other...

  13. 47 CFR 25.279 - Inter-satellite service.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 47 Telecommunication 2 2014-10-01 2014-10-01 false Inter-satellite service. 25.279 Section 25.279 Telecommunication FEDERAL COMMUNICATIONS COMMISSION (CONTINUED) COMMON CARRIER SERVICES SATELLITE COMMUNICATIONS Technical Operations § 25.279 Inter-satellite service. (a) Any satellite communicating with other...

  14. 47 CFR 25.279 - Inter-satellite service.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 47 Telecommunication 2 2013-10-01 2013-10-01 false Inter-satellite service. 25.279 Section 25.279 Telecommunication FEDERAL COMMUNICATIONS COMMISSION (CONTINUED) COMMON CARRIER SERVICES SATELLITE COMMUNICATIONS Technical Operations § 25.279 Inter-satellite service. (a) Any satellite communicating with other...

  15. 47 CFR 25.279 - Inter-satellite service.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 47 Telecommunication 2 2012-10-01 2012-10-01 false Inter-satellite service. 25.279 Section 25.279 Telecommunication FEDERAL COMMUNICATIONS COMMISSION (CONTINUED) COMMON CARRIER SERVICES SATELLITE COMMUNICATIONS Technical Operations § 25.279 Inter-satellite service. (a) Any satellite communicating with other...

  16. 47 CFR 25.279 - Inter-satellite service.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 47 Telecommunication 2 2010-10-01 2010-10-01 false Inter-satellite service. 25.279 Section 25.279 Telecommunication FEDERAL COMMUNICATIONS COMMISSION (CONTINUED) COMMON CARRIER SERVICES SATELLITE COMMUNICATIONS Technical Operations § 25.279 Inter-satellite service. (a) Any satellite communicating with other...

  17. The 18 and 30 GHz fixed service communications satellite system study. [to determine the cost and performance characteristics

    NASA Technical Reports Server (NTRS)

    Bronstein, L. M.

    1979-01-01

    The use of the 18 and 30 GHz bands for fixed service satellite communications is examined. The cost and performance expected of 18 and 30 GHz hardware is assessed, selected trunking and direct to user concepts are optimized, and the cost of these systems are estimated. The effect of rain attenuation on the technical and economic viability of the system and methods circumventing the problem are discussed. Technology developments are investigated and cost estimates of these developments are presented.

  18. International communications via satellite

    NASA Astrophysics Data System (ADS)

    McLucas, J. L.

    The evolution of communications satellite systems is traced in terms of technical capabilities and technological advances. The Communications Act of 1962 led to the establishment of INTELSAT on an international basis in 1964. The original 19 signatory nations has grown to over 100, and over 800 ground relay stations have been built. The INTELSAT system comprises spacecraft over the Atlantic, Pacific, and Indian Oceans and handles 2/3 of the world's international electronic communications and all transoceanic television. The 1965 Early Bird satellite had a 240 two-way telephone link capacity and weighed 38 kg, while the Intelsat V satellites, of which there will be nine, have increased the capacity to 20,000 voice circuits and Intelsat VI will double the number by 1993. Increasing demand for satellite communications links is driving the design and development of space platforms for multiple missions of communications, meteorological studies, and on-board switching and data processing in excess of current multiple satellite systems.

  19. Remote Psychiatric and Psychological Services via the Communications Technology Satellite (CTS).

    ERIC Educational Resources Information Center

    Covvey, H. Dominic; And Others

    To provide remote psychiatric services to a population in Moose Factory, Ontario, via satellite, digital data links will be used to provide 24-hour access to the psychiatric medical file system and the psychiatric patient register at University Hospital, London, Ontario, and to permit scoring and interpretation of standard psychological tests. The…

  20. Demand for satellite-provided domestic communications services up to the year 2000

    NASA Astrophysics Data System (ADS)

    Stevenson, S.; Poley, W.; Lekan, J.; Salzman, J. A.

    1984-11-01

    Three fixed service telecommunications demand assessment studies were completed for NASA by The Western Union Telegraph Company and the U.S. Telephone and Telegraph Corporation. They provided forecasts of the total U.S. domestic demand, from 1980 to the year 2000, for voice, data, and video services. That portion that is technically and economically suitable for transmission by satellite systems, both large trunking systems and customer premises services (CPS) systems was also estimated. In order to provide a single set of forecasts a NASA synthesis of the above studies was conducted. The services, associated forecast techniques, and data bases employed by both contractors were examined, those elements of each judged to be the most appropriate were selected, and new forecasts were made. The demand for voice, data, and video services was first forecast in fundamental units of call-seconds, bits/year, and channels, respectively. Transmission technology characteristics and capabilities were then forecast, and the fundamental demand converted to an equivalent transmission capacity. The potential demand for satellite-provided services was found to grow by a factor of 6, from 400 to 2400 equivalent 36 MHz satellite transponders over the 20-year period. About 80 percent of this was found to be more appropriate for trunking systems and 20 percent CPS.

  1. Demand for satellite-provided domestic communications services up to the year 2000

    NASA Technical Reports Server (NTRS)

    Stevenson, S.; Poley, W.; Lekan, J.; Salzman, J. A.

    1984-01-01

    Three fixed service telecommunications demand assessment studies were completed for NASA by The Western Union Telegraph Company and the U.S. Telephone and Telegraph Corporation. They provided forecasts of the total U.S. domestic demand, from 1980 to the year 2000, for voice, data, and video services. That portion that is technically and economically suitable for transmission by satellite systems, both large trunking systems and customer premises services (CPS) systems was also estimated. In order to provide a single set of forecasts a NASA synthesis of the above studies was conducted. The services, associated forecast techniques, and data bases employed by both contractors were examined, those elements of each judged to be the most appropriate were selected, and new forecasts were made. The demand for voice, data, and video services was first forecast in fundamental units of call-seconds, bits/year, and channels, respectively. Transmission technology characteristics and capabilities were then forecast, and the fundamental demand converted to an equivalent transmission capacity. The potential demand for satellite-provided services was found to grow by a factor of 6, from 400 to 2400 equivalent 36 MHz satellite transponders over the 20-year period. About 80 percent of this was found to be more appropriate for trunking systems and 20 percent CPS.

  2. Overview of commercial satellite communications

    NASA Astrophysics Data System (ADS)

    Beakley, G. W.

    1984-07-01

    A brief history of communications satellites is presented, taking into account the launching of Sputnik 1 in October 1957, the Explorer 1 in January of 1958, the launch of the Score as the world's first active communications satellite in December 1958, the Communications Satellite Act in 1962, and the launch of 'Early Bird' in 1964. The Intelsat satellites are considered along with maritime satellite communications, the U.S. domestic satellite systems, Alaskan satellite communications, cable television, broadcast TV stations, print media, the hotel/motel industry as a large market for satellite communications terminals, the opening of a minicable and satellite master antenna TV market for TV receive-only systems, and business telecommunications earth terminals. Attention is also given to future directions regarding satellite positions, the concept of 'video-plus', and direct broadcast satellites.

  3. Domestic satellite communications overview

    NASA Astrophysics Data System (ADS)

    Nickelson, R. L.

    1984-09-01

    The current status and future planning of satellite systems for intranational communication are examined in a summary of presentations given at the CCIR international seminar on domestic satellite communications held in Shanghai in October 1983. Topics discussed include operational and planned systems in Australia, Japan, the U.S., India, China, France, Brazil, Italy, Thailand, and the European region; development and planning by NASA and Intelsat; systems for rural areas or light traffic; modulation and multiple access; antennas, propagation, and interference; geostationary orbits; and economics, planning, and implementation.

  4. Cost Consideration for Future Communications Satellite

    NASA Astrophysics Data System (ADS)

    Iida, Takashi

    2002-01-01

    This paper discusses the cost driving factors of the future communications satellite rather than discussing its cost itself directly, in terms of development period of time, services, and R&D by government. In the first, a period of time for development of a communications system is discussed in comparison of satellite communications system with a terrestrial communications system. Generally speaking, the terrestrial communications system is developed in a short period. Especially, the recent network related IT technology changes very rapidly, like so-called as "Dog Year". On the other hand, it takes a long time, more than several years, to develop a satellite communications system. This paper will discuss this time period of development is how to influence the system realization in various cases. In the second, the service related cost is discussed. First, a mobile communications satellite system is considered as an example. The tremendous penetration speed of the terrestrial cellular phones prevents from the success of the mobile satellite communications system. The success of the mobile satellite communications system depends on how early and user friendly to develop its user terminals. Second, the broadcasting service is described as a successful example. It is described that the satellite broadcasting has a very competitive advantage to the terrestrial broadcasting service from the cost point of view. Finally, the cost of the technology R&D for the future communication satellite by the government is discussed. A model of the future communications satellite for next 30 years has been proposed(1)(2). As an example, this paper estimates the satellite cost of the 60 Gbps range of capacity which is called as 1.5G satellite, where the capacity of the second generation Internet satellite (2G) is 50-500 Gbps per satellite. In the paper, the R&D plan of the future communications satellite will be discussed as a next R&D project to the first generation Internet satellite from a cost point of view. References (1)T.Iida and Y.Suzuki: "Satellite Communications R&D for Next 30 Years", 19th AIAA (2)T.Iida, Y.Suzuki and A.Akaishi: "Satellite Communications R&D for Next 30 Years:

  5. 75 FR 13085 - Pan-Pacific Education and Communications Experiments by Satellite (PEACESAT): Closing Date

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-03-18

    ...acquisition of satellite communications to service Pacific...Pan-Pacific Education and Communications Experiments by Satellite...acquire satellite communications services to provide...educational, medical, and cultural needs of Pacific...

  6. Satellite services system overview

    NASA Technical Reports Server (NTRS)

    Rysavy, G.

    1982-01-01

    The benefits of a satellite services system and the basic needs of the Space Transportation System to have improved satellite service capability are identified. Specific required servicing equipment are discussed in terms of their technology development status and their operative functions. Concepts include maneuverable television systems, extravehicular maneuvering unit, orbiter exterior lighting, satellite holding and positioning aid, fluid transfer equipment, end effectors for the remote manipulator system, teleoperator maneuvering system, and hand and power tools.

  7. Satellite Services Workshop, Volume 1

    NASA Technical Reports Server (NTRS)

    1982-01-01

    Key issues associated with the orbital servicing of satellites are examined including servicing spacecraft and equipment, servicing operations, economics, satellite design, docking and berthing, and fluid management.

  8. Business Use of Satellite Communications.

    ERIC Educational Resources Information Center

    Edelson, Burton I.; Cooper, Robert S.

    1982-01-01

    Reviews business communications development and discusses business applications of satellite communications, system technology, and prospects for future developments in digital transmission systems. (JN)

  9. Low Earth orbit communications satellite

    NASA Technical Reports Server (NTRS)

    Moroney, D.; Lashbrook, D.; Mckibben, B.; Gardener, N.; Rivers, T.; Nottingham, G.; Golden, B.; Barfield, B.; Bruening, J.; Wood, D.

    1992-01-01

    A current thrust in satellite communication systems considers a low-Earth orbiting constellations of satellites for continuous global coverage. Conceptual design studies have been done at the time of this design project by LORAL Aerospace Corporation under the program name GLOBALSTAR and by Motorola under their IRIDIUM program. This design project concentrates on the spacecraft design of the GLOBALSTAR low-Earth orbiting communication system. Overview information on the program was gained through the Federal Communications Commission licensing request. The GLOBALSTAR system consists of 48 operational satellites positioned in a Walker Delta pattern providing global coverage and redundancy. The operational orbit is 1389 km (750 nmi) altitude with eight planes of six satellites each. The orbital planes are spaced 45 deg., and the spacecraft are separated by 60 deg. within the plane. A Delta 2 launch vehicle is used to carry six spacecraft for orbit establishment. Once in orbit, the spacecraft will utilize code-division multiple access (spread spectrum modulation) for digital relay, voice, and radio determination satellite services (RDSS) yielding position determination with accuracy up to 200 meters.

  10. Public service communications

    NASA Technical Reports Server (NTRS)

    Whalen, A. A.

    1979-01-01

    The purpose of the paper is to construct, for detailed analysis, satellite and terrestrial communications delivery system models. Attention is given to the Public Service Communications Delivery System Architectural Study, that takes advantage of the extensive experience which exists among the public service experimenters. The Application Test Pilot is examined, which is a program designed to help awareness, in a practical sense, of the technology available and by the users innovative talents, adapts the technology to solve their problems.

  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. Future communications satellite applications

    NASA Technical Reports Server (NTRS)

    Bagwell, James W.

    1992-01-01

    The point of view of the research is made through the use of viewgraphs. It is suggested that future communications satellite applications will be made through switched point to point narrowband communications. Some characteristics of which are as follows: small/low cost terminals; single hop communications; voice compatible; full mesh networking; ISDN compatible; and possible limited use of full motion video. Some target applications are as follows: voice/data networks between plants and offices in a corporation; data base networking for commercial and science users; and cellular radio internodal voice/data networking.

  13. 47 CFR 25.225 - Geographic Service Requirements for 17/24 GHz Broadcasting Satellite Service.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ...Requirements for 17/24 GHz Broadcasting Satellite Service. 25.225 Section 25.225...CONTINUED) COMMON CARRIER SERVICES SATELLITE COMMUNICATIONS Technical Standards...Requirements for 17/24 GHz Broadcasting Satellite Service. (a) Each...

  14. Activities of Canadian Satellite Communications, Inc.

    NASA Astrophysics Data System (ADS)

    1992-12-01

    Canadian Satellite Communications (Cancom) has as its core business the provision of television and radio signals to cable systems in Canada, with the objective of making affordable broadcast signals available to remote and/or small communities. Cancom also provides direct-to-home services to backyard receiving dishes, as well as satellite digital data business communications services, satellite business television, and satellite network services. Its business communication services range from satellite links for big-city businesses with small branch operations located far from major centers, to a mobile messaging and tracking system for the trucking industry. Revenues in 1992 totalled $48,212,000 and net income was just over $7 million. Cancom bought 10 percent interest in Leosat Corp. of Washington, DC, who are seeking approval to operate a position locator network from low-orbit satellites. Cancom has also become a partner in SovCan Star Satellite Communications Inc., which will build an international satellite system in partnership with Russia. The first satellite in this east-west business network will be placed in a Russian orbital slot over the Atlantic by 1996, and a second satellite will follow for the Pacific region. This annual report of Cancom's activities for 1992 includes financial statements and a six year financial review.

  15. A potential 21st century satellite communications application - Personal communications

    NASA Astrophysics Data System (ADS)

    Tsang, E. K.; Douville, R.

    1990-03-01

    It has been forecast that not only will the future needs for satellite communications grow, especially in the area of broadcasting and mobile services, but also that the requirements will be diversified. For voice and data traffic, satellite communications started with the requirements of the telephone companies. Over the past few years, with the availability of Ku-band and VSAT systems, private business networks have emerged. Heading into the 21st century, satellite communications will expand into the personal services domain. This paper describes a concept for a satellite-based personal radio system. To realize the personal communications system, the portable terminals have to be inexpensive and small, similar to the present portable or handheld cellular radio-phones in size. The system aspects, such as selection of frequency band, multiple access and payload configuration will be addressed. The advanced technology required for the portable personal satellite communications system will be discussed.

  16. Satellite Services Rate Schedule Effective March 26, 2014

    E-print Network

    Acton, Scott

    Satellite Services Rate Schedule Effective March 26, 2014 SCPS offers satellite communications Satellite Services email satellite@virginia.edu or call 434-982-5268. Services UVa/State Regular* UVa Studio to Vyvx $335 $500 $400 $600 IFB & PL $15 $20 $20 $30 Tape Playback $65 $100 $85 $125 Satellite

  17. Experimental Satellite Quantum Communications

    NASA Astrophysics Data System (ADS)

    Vallone, Giuseppe; Bacco, Davide; Dequal, Daniele; Gaiarin, Simone; Luceri, Vincenza; Bianco, Giuseppe; Villoresi, Paolo

    2015-07-01

    Quantum communication (QC), namely, the faithful transmission of generic quantum states, is a key ingredient of quantum information science. Here we demonstrate QC with polarization encoding from space to ground by exploiting satellite corner cube retroreflectors as quantum transmitters in orbit and the Matera Laser Ranging Observatory of the Italian Space Agency in Matera, Italy, as a quantum receiver. The quantum bit error ratio (QBER) has been kept steadily low to a level suitable for several quantum information protocols, as the violation of Bell inequalities or quantum key distribution (QKD). Indeed, by taking data from different satellites, we demonstrate an average value of QBER =4.6 % for a total link duration of 85 s. The mean photon number per pulse ?sat leaving the satellites was estimated to be of the order of one. In addition, we propose a fully operational satellite QKD system by exploiting our communication scheme with orbiting retroreflectors equipped with a modulator, a very compact payload. Our scheme paves the way toward the implementation of a QC worldwide network leveraging existing receivers.

  18. Experimental Satellite Quantum Communications.

    PubMed

    Vallone, Giuseppe; Bacco, Davide; Dequal, Daniele; Gaiarin, Simone; Luceri, Vincenza; Bianco, Giuseppe; Villoresi, Paolo

    2015-07-24

    Quantum communication (QC), namely, the faithful transmission of generic quantum states, is a key ingredient of quantum information science. Here we demonstrate QC with polarization encoding from space to ground by exploiting satellite corner cube retroreflectors as quantum transmitters in orbit and the Matera Laser Ranging Observatory of the Italian Space Agency in Matera, Italy, as a quantum receiver. The quantum bit error ratio (QBER) has been kept steadily low to a level suitable for several quantum information protocols, as the violation of Bell inequalities or quantum key distribution (QKD). Indeed, by taking data from different satellites, we demonstrate an average value of QBER=4.6% for a total link duration of 85 s. The mean photon number per pulse ?_{sat} leaving the satellites was estimated to be of the order of one. In addition, we propose a fully operational satellite QKD system by exploiting our communication scheme with orbiting retroreflectors equipped with a modulator, a very compact payload. Our scheme paves the way toward the implementation of a QC worldwide network leveraging existing receivers. PMID:26252672

  19. Interim Service ISDN Satellite (ISIS) network model for advanced satellite designs and experiments

    NASA Technical Reports Server (NTRS)

    Pepin, Gerard R.; Hager, E. Paul

    1991-01-01

    The Interim Service Integrated Services Digital Network (ISDN) Satellite (ISIS) Network Model for Advanced Satellite Designs and Experiments describes a model suitable for discrete event simulations. A top-down model design uses the Advanced Communications Technology Satellite (ACTS) as its basis. The ISDN modeling abstractions are added to permit the determination and performance for the NASA Satellite Communications Research (SCAR) Program.

  20. AUSSAT mobile satellite services

    NASA Technical Reports Server (NTRS)

    Nowland, Wayne L.; Wagg, Michael; Simpson, Daniel

    1988-01-01

    An overview of AUSSAT's planned mobile satellite system is given. The development program which is being undertaken to achieve the 1992 service date is described. Both business and technical aspects of the development program are addressed.

  1. Satellite communications for disaster relief operations

    NASA Technical Reports Server (NTRS)

    Sivo, J. N.

    1979-01-01

    The use of existing and planned communication satellite systems to provide assistance in the implementation of disaster relief operations on a global basis was discussed along with satellite communications system implications and their potential impact on field operations in disaster situations. Consideration are given to the utilization of both INTELSAT and MARISAT systems operating at frequencies ranging from 1.5 to 4 GHz and to the size and type of ground terminals necessary for satellite access. Estimates of communication requirements for a global system are given. Some discussion of cost estimates for satellite services to support operations are included. Studies of communication satellites for both pre and post disaster applications conducted for NOAA are included as well as recent experiments conducted in conjunction with the Office of Foreign Disaster Assistance of the Agency for International Development.

  2. Survey: National Environmental Satellite Service

    NASA Technical Reports Server (NTRS)

    1977-01-01

    The national Environmental Satellite Service (NESS) receives data at periodic intervals from satellites of the Synchronous Meteorological Satellite/Geostationary Operational Environmental Satellite series and from the Improved TIROS (Television Infrared Observational Satellite) Operational Satellite. Within the conterminous United States, direct readout and processed products are distributed to users over facsimile networks from a central processing and data distribution facility. In addition, the NESS Satellite Field Stations analyze, interpret, and distribute processed geostationary satellite products to regional weather service activities.

  3. Satellite Applications for Public Service: Project Summaries.

    ERIC Educational Resources Information Center

    Lauffer, Sandra; And Others

    Summaries of 18 different projects involving the use of satellite communications are presented in this report, including PEACESAT Education and Communication Experiments, USP Network Satellite Communication Project, Project Satellite, Satellite Instructional Television Experiment (SITE), Appalachian Education Satellite Program, Alaska Education…

  4. 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.

  5. Mobile satellite service in the United States

    NASA Technical Reports Server (NTRS)

    Agnew, Carson E.; Bhagat, Jai; Hopper, Edwin A.; Kiesling, John D.; Exner, Michael L.; Melillo, Lawrence; Noreen, Gary K.; Parrott, Billy J.

    1988-01-01

    Mobile satellite service (MSS) has been under development in the United States for more than two decades. The service will soon be provided on a commercial basis by a consortium of eight U.S. companies called the American Mobile Satellite Consortium (AMSC). AMSC will build a three-satellite MSS system that will offer superior performance, reliability and cost effectiveness for organizations requiring mobile communications across the U.S. The development and operation of MSS in North America is being coordinated with Telesat Canada and Mexico. AMSC expects NASA to provide launch services in exchange for capacity on the first AMSC satellite for MSAT-X activities and for government demonstrations.

  6. 47 CFR 25.212 - Narrowband analog transmissions and digital transmissions in the GSO Fixed Satellite Service.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ...digital transmissions in the GSO Fixed Satellite Service. 25.212 Section 25.212 Telecommunication FEDERAL COMMUNICATIONS COMMISSION (CONTINUED) COMMON CARRIER SERVICES SATELLITE COMMUNICATIONS Technical Standards §...

  7. 47 CFR 25.225 - Geographic Service Requirements for 17/24 GHz Broadcasting Satellite Service.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... Broadcasting Satellite Service. 25.225 Section 25.225 Telecommunication FEDERAL COMMUNICATIONS COMMISSION (CONTINUED) COMMON CARRIER SERVICES SATELLITE COMMUNICATIONS Technical Standards § 25.225 Geographic Service Requirements for 17/24 GHz Broadcasting Satellite Service. (a) Each operator of a 17/24 GHz BSS space...

  8. 47 CFR 25.225 - Geographic Service Requirements for 17/24 GHz Broadcasting Satellite Service.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... Broadcasting Satellite Service. 25.225 Section 25.225 Telecommunication FEDERAL COMMUNICATIONS COMMISSION (CONTINUED) COMMON CARRIER SERVICES SATELLITE COMMUNICATIONS Technical Standards § 25.225 Geographic Service Requirements for 17/24 GHz Broadcasting Satellite Service. (a) Each operator of a 17/24 GHz BSS space...

  9. 47 CFR 25.225 - Geographic Service Requirements for 17/24 GHz Broadcasting Satellite Service.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... Broadcasting Satellite Service. 25.225 Section 25.225 Telecommunication FEDERAL COMMUNICATIONS COMMISSION (CONTINUED) COMMON CARRIER SERVICES SATELLITE COMMUNICATIONS Technical Standards § 25.225 Geographic Service Requirements for 17/24 GHz Broadcasting Satellite Service. (a) Each operator of a 17/24 GHz BSS space...

  10. 47 CFR 25.225 - Geographic Service Requirements for 17/24 GHz Broadcasting Satellite Service.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... Broadcasting Satellite Service. 25.225 Section 25.225 Telecommunication FEDERAL COMMUNICATIONS COMMISSION (CONTINUED) COMMON CARRIER SERVICES SATELLITE COMMUNICATIONS Technical Standards § 25.225 Geographic Service Requirements for 17/24 GHz Broadcasting Satellite Service. (a) Each operator of a 17/24 GHz BSS space...

  11. 47 CFR 25.225 - Geographic Service Requirements for 17/24 GHz Broadcasting Satellite Service.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... Broadcasting Satellite Service. 25.225 Section 25.225 Telecommunication FEDERAL COMMUNICATIONS COMMISSION (CONTINUED) COMMON CARRIER SERVICES SATELLITE COMMUNICATIONS Technical Standards § 25.225 Geographic Service Requirements for 17/24 GHz Broadcasting Satellite Service. (a) Each operator of a 17/24 GHz BSS space...

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

    NASA Astrophysics Data System (ADS)

    Hornig, Andreas; Homeister, Maren

    2015-03-01

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

  13. Satellite servicing economic study

    NASA Technical Reports Server (NTRS)

    1990-01-01

    Previous studies have shown that satellite servicing is cost effective; however, all of these studies were of different formats, dollar year, learning rates, availability, etc. Therefore, it was difficult to correlate any useful trends from these studies. The reviewed study was initiated to correlate the economic data into a common data base, using a common set of assumptions. A selected set of existed funded programs was then analyzed to provide an independent analysis of the servicing options and potential economic benefits.

  14. Satellite servicing economic study

    NASA Technical Reports Server (NTRS)

    1990-01-01

    Previous studies have shown that satellite servicing is cost effective; however, all of these studies were of different formats, dollar year, learning rates, availability, etc. Threfore, it was difficult to correlate any useful trends from these studies. The reviewed study was initiated to correlate the economic data into a common data base, using a common set of assumptions. A selected set of existed funded programs was then analyzed to provide an independent analysis of the servicing options and potential economic benefits.

  15. Satellites extend communications to remote areas

    SciTech Connect

    Amey, S.

    1996-10-01

    The advent of new communications technologies has played a lead role in building the global village, enabling companies to conduct international business more cost-efficiently, especially when an increasing number of companies are exploring remote parts of the world with minimal or non-existent infrastructure. Both voice and data communications have become significant challenges in these undeveloped areas. To solve this problem, oil and gas companies have begun relying on satellite communications. Recent advances in technology and new satellite systems being developed will enable companies to select from a broader range of services and price options.

  16. Trends in mobile satellite communication

    NASA Technical Reports Server (NTRS)

    Johannsen, Klaus G.; Bowles, Mike W.; Milliken, Samuel; Cherrette, Alan R.; Busche, Gregory C.

    1993-01-01

    Ever since the U.S. Federal Communication Commission opened the discussion on spectrum usage for personal handheld communication, the community of satellite manufacturers has been searching for an economically viable and technically feasible satellite mobile communication system. Hughes Aircraft Company and others have joined in providing proposals for such systems, ranging from low to medium to geosynchronous orbits. These proposals make it clear that the trend in mobile satellite communication is toward more sophisticated satellites with a large number of spot beams and onboard processing, providing worldwide interconnectivity. Recent Hughes studies indicate that from a cost standpoint the geosynchronous satellite (GEOS) is most economical, followed by the medium earth orbit satellite (MEOS) and then by the low earth orbit satellite (LEOS). From a system performance standpoint, this evaluation may be in reverse order, depending on how the public will react to speech delay and collision. This paper discusses the trends and various mobile satellite constellations in satellite communication under investigation. It considers the effect of orbital altitude and modulation/multiple access on the link and spacecraft design.

  17. Modulation and coding used by a major satellite communications company

    NASA Technical Reports Server (NTRS)

    Renshaw, K. H.

    1992-01-01

    Hughes Communications Inc., is a major satellite communications company providing or planning to provide the full spectrum of services available on satellites. All of the current services use conventional modulation and coding techniques that were well known a decade or longer ago. However, the future mobile satellite service will use significantly more advanced techniques. JPL, under NASA sponsorship, has pioneered many of the techniques that will be used.

  18. Coding for reliable satellite communications

    NASA Astrophysics Data System (ADS)

    Gaarder, N. T.; Lin, S.

    1986-07-01

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

  19. Global trade in satellites and launch services

    NASA Astrophysics Data System (ADS)

    Hearing before the Subcommittee on Space of the Committee on Science, Space, and Technology of the House of Representatives is presented. Written testimony, submittals for the record, and responses to written questions are included. Topics concerning the global trade in satellites and launch services include foreign competition, the China and Russia trade agreements, Commerce licensing on international sales and export, trade control, technology transfer, satellite communications and the economy, satellites and the global information infrastructure, commercial space revenues, and enforcement of trade policies.

  20. Navy satellite communications systems in transition

    NASA Astrophysics Data System (ADS)

    Newell, J. W.

    Navy SATCOM programs require advanced system engineering, program management, and long range planning to improve satellite and ground system technology. Solutions are being sought to develop Navy transitional issues within the framework of the total Defense MILSATCOM architecture. Several of the Navy SATCOM transition issues are discussed: the current Navy SATCOM baseline, consisting of three GAPFILLER (MARISAT) satellites and a constellation of geosynchronous FLTSATCOM satellites; a Demand Assignment time-division Multiple Access (DAMA) system, which permits a more efficient use of the 25 kHz FLTSAT hard-limiting transponders. A leased satellite (LEASAT) will provide extended UHF SATCOM service at four geosynchronous orbital locations. The navy also plans to increase connectivity, capacity, and AJ protection of Fleet Satellite Communications by introduction of SHF service.

  1. 78 FR 14920 - Earth Stations Aboard Aircraft Communicating With Fixed-Satellite Service Geostationary-Orbit...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-03-08

    ...Satellite System (TDRSS). (b) In the band 14.47-14.5 GHz, operations within radio line-of- sight of the radio astronomy stations specified in 47 CFR 25.226(d)(2) are subject to coordination with the National Science Foundation in...

  2. 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.

  3. A design of 30/20 GHz flight communications experiment for NASA. [satellite and earth segments for high data rate commercial service

    NASA Technical Reports Server (NTRS)

    Kawamoto, Y.

    1982-01-01

    The objective of the 30/20 GHz Flight Experiment System is to develop the required technology and to experiment with the communication technique for an operational communication satellite system. The system uses polarization, spatial, and frequency isolations to maximize the spectrum utilization. The key spacecraft technologies required for the concept are the scan beam antenna, the baseband processor, the IF switch matrix, TWTA, SSPA, and LNA. The spacecraft communication payload information will be telemetered and monitored closely so that these technologies and performances can be verified. Two types of services, a trunk service and a customer premise service, are demonstrated in the system. Many experiments associated with these services, such as synchronization, demand assignment, link control, and network control will be performed to provide important information on the operational aspect of the system.

  4. Technology requirements for post-1985 communications satellites

    NASA Technical Reports Server (NTRS)

    Burtt, J. E.; Moe, C. R.; Elms, R. V.; Delateur, L. A.; Sedlacek, W. C.; Younger, G. G.

    1973-01-01

    The technical and functional requirements for commercial communication satellites are discussed. The need for providing quality service at an acceptable cost is emphasized. Specialized services are postulated in a needs model which forecasts future demands. This needs model is based upon 322 separately identified needs for long distance communication. It is shown that the 1985 demand for satellite communication service for a domestic region such as the United States, and surrounding sea and air lanes, may require on the order of 100,000 MHz of bandwith. This level of demand can be met by means of the presently allocated bandwidths and developing some key technologies. Suggested improvements include: (1) improving antennas so that high speed switching will be possible; (2) development of solid state transponders for 12 GHz and possibly higher frequencies; (3) development of switched or steered beam antennas with 10 db or higher gain for aircraft; and (4) continued development of improved video channel compression techniques and hardware.

  5. Potential markets for advanced satellite communications

    NASA Technical Reports Server (NTRS)

    Adamson, Steven; Roberts, David; Schubert, Leroy; Smith, Brian; Sogegian, Robert; Walters, Daniel

    1993-01-01

    This report identifies trends in the volume and type of traffic offered to the U.S. domestic communications infrastructure and extrapolates these trends through the year 2011. To describe how telecommunications service providers are adapting to the identified trends, this report assesses the status, plans, and capacity of the domestic communications infrastructure. Cable, satellite, and radio components of the infrastructure are examined separately. The report also assesses the following major applications making use of the infrastructure: (1) Broadband services, including Broadband Integrated Services Digital Network (BISDN), Switched Multimegabit Data Service (SMDS), and frame relay; (2) mobile services, including voice, location, and paging; (3) Very Small Aperture Terminals (VSAT), including mesh VSAT; and (4) Direct Broadcast Satellite (DBS) for audio and video. The report associates satellite implementation of specific applications with market segments appropriate to their features and capabilities. The volume and dollar value of these market segments are estimated. For the satellite applications able to address the needs of significant market segments, the report also examines the potential of each satellite-based application to capture business from alternative technologies.

  6. Interim Service ISDN Satellite (ISIS) simulator development for advanced satellite designs and experiments

    NASA Technical Reports Server (NTRS)

    Pepin, Gerard R.

    1992-01-01

    The simulation development associated with the network models of both the Interim Service Integrated Services Digital Network (ISDN) Satellite (ISIS) and the Full Service ISDN Satellite (FSIS) architectures is documented. The ISIS Network Model design represents satellite systems like the Advanced Communications Technology Satellite (ACTS) orbiting switch. The FSIS architecture, the ultimate aim of this element of the Satellite Communications Applications Research (SCAR) Program, moves all control and switching functions on-board the next generation ISDN communications satellite. The technical and operational parameters for the advanced ISDN communications satellite design will be obtained from the simulation of ISIS and FSIS engineering software models for their major subsystems. Discrete event simulation experiments will be performed with these models using various traffic scenarios, design parameters, and operational procedures. The data from these simulations will be used to determine the engineering parameters for the advanced ISDN communications satellite.

  7. NASA compendium of satellite communications programs

    NASA Technical Reports Server (NTRS)

    1971-01-01

    A comprehensive review of worldwide satellite communication programs is reported that ranges in time from the inception of satellite communications to mid-1971. Particular emphasis is placed on program results, including experiments conducted, communications system operational performance, and technology employed.

  8. 78 FR 14920 - Earth Stations Aboard Aircraft Communicating With Fixed-Satellite Service Geostationary-Orbit...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-03-08

    ... licensing of two-way in-flight broadband services, including Internet access, to passengers and flight crews... Notice of Proposed Rulemaking in IB Docket No. 05-20 (Order) (70 FR 20508-01), recognizing the emergence..., DC 20554. The document is also available for download over the Internet at...

  9. The developments of satellite communications of China

    NASA Astrophysics Data System (ADS)

    Liu, Shen

    1993-03-01

    Present status of satellite communication system development in China is introduced. An overview of the space segment arrangements of international or regional satellites for domestic satellite telecommunication, trunk routes, provincial and regional satellite links, VSAT (Very Small Aperture Terminal) applications for data transmissions, and international satellite communications is presented.

  10. 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.

  11. A series on optimizing satellite systems. I - Restoring interruptions of communications sattelite service: Logistical and cost comparisons of mature and newly operational systems

    NASA Astrophysics Data System (ADS)

    Snow, Marcellus S.

    1989-09-01

    A mathematical model is presented of costs and operational factors involved in provision for service interruptions of both a mature and typically large incumbent satellite system and of a smaller, more recently operational system. The equation expresses the required launch frequency for the new system as a function of the launch spacing of the mature system; the time disparity between the inauguration of the two systems; and the rate of capacity depreciation. In addition, a technique is presented to compare the relative extent to which the discounted costs of the new system exceed those of the mature system in furnishing the same effective capacity in orbit, and thus the same service liability, at a given point in time. It is determined that a mature incumbent communications satellite system, having more capacity in orbit, will on balance have a lower probability of service interruption than a newer, smaller system.

  12. Fleet satellite communications /FLTSATCOM/ program

    NASA Astrophysics Data System (ADS)

    Melancon, P. S.; Smith, R. D.

    The FLTSATCOM satellite is the spaceborne element of a worldwide Department of Defense tactical communication system. The U.S. Navy, U.S. Air Force, and other DOD agencies are users, for which the system is satisfying Fleet Broadcast, Single Integrated Operating Plan, and Presidential support requirements. Two satellites are now operational with the third, fourth, and fifth satellite planned for launch in early 1980 to mid-1981. This paper discusses the test program and explores test philosophy including the corrective action feedback process resulting from component failures. It is shown that the total number of test discrepancies were small in number in relation to the complexity of the spacecraft.

  13. Mobile satellite service for Canada

    NASA Technical Reports Server (NTRS)

    Sward, David

    1988-01-01

    The Mobile Satellite (MSAT) system and a special program designed to provide interim mobile satellite services (IMSS) during the construction phase of MSAT are described. A mobile satellite system is a key element in extending voice and and data telecommunications to all Canadians.

  14. Customer concerns regarding satellite servicing

    NASA Technical Reports Server (NTRS)

    Rysavy, Gordon

    1987-01-01

    The organization of orbital servicing of satellites is discussed. Provision of servicing equipment; design interfaces between the satellite and the servicing equipment; and the economic viability of the concept are discussed. The proposed solution for satisfying customer concerns is for the servicing organizations to baseline an adequate inventory of servicing equipment with standard interfaces and established servicing costs. With this knowledge, the customer can conduct tradeoff studies and make programmatic decisions regarding servicing options. A dialog procedure between customers and servicing specialists is outlined.

  15. Federal research and development for satellite communications

    NASA Technical Reports Server (NTRS)

    1977-01-01

    A Committee on Satellite Communication (COSC) was formed under the auspices of the Space Applications Board (SAB) in order to study Federal research and development on satellite communications (SC). Discussion on whether to continue the research and development and the proper role of the Federal Government are addressed. Discussion focussed on six possible options for a Federal role in SC research and development: (1) the current NASA SC program; (2) an expanded NASA SC technology program; (3) a SC technology flight test support program; (4) an experimental SC technology flight program; (5) an experimental public service SC system program; and (6) an operational public service SC system program. Decision criteria and recommendations are presented.

  16. Satellite communications for the Pacific islands. Second year report

    NASA Technical Reports Server (NTRS)

    Young, E.; Hurd, J. N.

    1982-01-01

    Requirements, options and costs for use of communications satellites in underserved areas of the Pacific Basin are described with emphasis on extended utilization of INTELSAT. The economic structures within and among Pacific Basin entities are examined, particularly the relationship between the growth of regional trade and telecommunications potential for the region. Suitable satellite services are recommended and the financial implications for extended utilization of communications satellites in the Pacific Basin are considered.

  17. Advanced mobile satellite communications using COMETS satellite in MM-wave and Ka-band

    NASA Technical Reports Server (NTRS)

    Ohmori, Shingo; Isobe, Shunkichi; Takeuchi, Makoto; Naito, Hideyuki

    1993-01-01

    Early in the 21st century, the demand for personal communications using mobile, hand-held, and VSAT terminals will rapidly increase. In a future system, many different types of services should be provided with one-hop connection. The Communications Research Laboratory (CRL) has studied a future advanced mobile satellite communications system using millimeter wave and Ka band. In 1990, CRL started the Communications and Broadcasting Engineering Test Satellite (COMETS) project. The satellite has been developed in conjunction with NASDA and will be launched in 1997. This paper describes the COMETS payload configuration and the experimental system for the advanced mobile communications mission.

  18. The Aerospace Corporation 2009 Communication Satellite Systems

    E-print Network

    Low, Steven H.

    © The Aerospace Corporation 2009 Communication Satellite Systems Trends and Network Aspects Paul://www.aero.org/ Lee Center, Caltech 13 April 2009 #12;22 Communication Satellites · Brief History by Decade · Trends: ­ Communication Satellites, fifth edition, by D. Martin, P. Anderson, L. Bartamian, Aerospace / AIAA Press, 2006

  19. China's operational communication satellite DFH-2A

    NASA Astrophysics Data System (ADS)

    Liu, Jierong; Li, Hua

    1992-06-01

    A brief description of the DFH-2A communication satellites, which are the second generation of China's domestic communication satellites, is presented. These satellites, four of which were launched from March 7, 1988 to December 28, 1991, have been used for CCTVs, local TV program transmission, domestic communications, and broadcasting to foreign countries.

  20. Telemammography Using Satellite Communications

    NASA Technical Reports Server (NTRS)

    1996-01-01

    Telemammography, the electronic transmission of digitized mammograms, can connect patients with timely, critical medical expertise; howev er, an adequate terrestrial communications infrastructure does not exist in these areas. NASA Lewis Research Center's Advanced Space Commu nications Laboratory is now working with leading breast cancer resear ch hospitals, including the Cleveland Clinic and the University of Virginia, to perform the critical research necessary to allow new satell ite networks to support telemammography.

  1. Satellite communications systems and technology. Volume 1: Analytical chapters

    NASA Technical Reports Server (NTRS)

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

    1993-01-01

    This is Volume 1 (Analytical Chapters) of the final report of the NASA/NSF Panel Satellite Communications Systems and Technology. The panel surveyed advanced technology being developed for commercial use in the satellite communications field in Europe, Japan, and Russia. All aspects of satellite communications were considered, including fixed, broadcast, mobile, personal communications, navigation, low earth orbit, and small satellites. The focus was on experimental and advanced technology being developed in R&D and demonstration programs rather than on today's production capabilities. Focus was on commercial satellite technology, and does not review defense-related or other confidential satellite communications capabilities. The NASA/NSF panel concluded that the United States has lost its leading position in many critical satellite communications technologies. Although U.S. industry retains a leading position in today's marketplace for satellite communications systems and services, this position is largely founded on technologies and capabilities developed in the 1960's and 1970's. Because the United States is losing ground with respect to a wide range of technologies and systems that will be key to future communications markets, the market share of the U.S. satellite communications industry is at risk.

  2. Satellite communications systems and technology. Volume 1; Analytic Chapters

    NASA Technical Reports Server (NTRS)

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

    1993-01-01

    Volume 1 (Analytical Chapters) of the final report of the NASA/NSF Panel Satellite Communications Systems and Technology is presented. The panel surveyed advanced technology being developed for commercial use in the satellite communications field in Europe, Japan, and Russia. All aspects of satellite communications were considered, including fixed, broadcast, mobile, personal communications, navigation, low earth orbit, and small satellites. The focus of the study was on experimental and advanced technology being developed in R&D and demonstration programs rather than on today's production capabilities. The report focuses on commercial satellite technology, and does not review defense-related or other confidential satellite communications capabilities. The NASA/NSF panel concluded that the United States has lost its leading position in many critical satellite communications technologies. Although U.S. industry retains a leading position in today's marketplace for satellite communications systems and services, this position is largely founded on technologies and capabilities developed in the 1960s and 1970s. Because the United States is losing ground with respect to a wide range of technologies and systems that will be key to future communications markets, the market share of the U.S. satellite communications industry is at risk.

  3. 47 CFR 25.143 - Licensing provisions for the 1.6/2.4 GHz Mobile-Satellite Service and 2 GHz Mobile-Satellite...

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ...-Satellite Service and 2 GHz Mobile-Satellite Service. 25.143 Section 25.143 Telecommunication FEDERAL COMMUNICATIONS COMMISSION (CONTINUED) COMMON CARRIER SERVICES SATELLITE COMMUNICATIONS Applications and Licenses Space Stations § 25.143 Licensing provisions for the 1.6/2.4 GHz Mobile-Satellite Service and 2...

  4. 47 CFR 25.143 - Licensing provisions for the 1.6/2.4 GHz mobile-satellite service and 2 GHz mobile-satellite...

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ...-satellite service and 2 GHz mobile-satellite service. 25.143 Section 25.143 Telecommunication FEDERAL COMMUNICATIONS COMMISSION (CONTINUED) COMMON CARRIER SERVICES SATELLITE COMMUNICATIONS Applications and Licenses Space Stations § 25.143 Licensing provisions for the 1.6/2.4 GHz mobile-satellite service and 2...

  5. 47 CFR 25.143 - Licensing provisions for the 1.6/2.4 GHz Mobile-Satellite Service and 2 GHz Mobile-Satellite...

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ...-Satellite Service and 2 GHz Mobile-Satellite Service. 25.143 Section 25.143 Telecommunication FEDERAL COMMUNICATIONS COMMISSION (CONTINUED) COMMON CARRIER SERVICES SATELLITE COMMUNICATIONS Applications and Licenses Space Stations § 25.143 Licensing provisions for the 1.6/2.4 GHz Mobile-Satellite Service and 2...

  6. 47 CFR 25.143 - Licensing provisions for the 1.6/2.4 GHz mobile-satellite service and 2 GHz mobile-satellite...

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ...-satellite service and 2 GHz mobile-satellite service. 25.143 Section 25.143 Telecommunication FEDERAL COMMUNICATIONS COMMISSION (CONTINUED) COMMON CARRIER SERVICES SATELLITE COMMUNICATIONS Applications and Licenses Space Stations § 25.143 Licensing provisions for the 1.6/2.4 GHz mobile-satellite service and 2...

  7. 47 CFR 25.143 - Licensing provisions for the 1.6/2.4 GHz mobile-satellite service and 2 GHz mobile-satellite...

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ...-satellite service and 2 GHz mobile-satellite service. 25.143 Section 25.143 Telecommunication FEDERAL COMMUNICATIONS COMMISSION (CONTINUED) COMMON CARRIER SERVICES SATELLITE COMMUNICATIONS Applications and Licenses Space Stations § 25.143 Licensing provisions for the 1.6/2.4 GHz mobile-satellite service and 2...

  8. Research Supporting Satellite Communications Technology

    NASA Technical Reports Server (NTRS)

    Horan Stephen; Lyman, Raphael

    2005-01-01

    This report describes the second year of research effort under the grant Research Supporting Satellite Communications Technology. The research program consists of two major projects: Fault Tolerant Link Establishment and the design of an Auto-Configurable Receiver. The Fault Tolerant Link Establishment protocol is being developed to assist the designers of satellite clusters to manage the inter-satellite communications. During this second year, the basic protocol design was validated with an extensive testing program. After this testing was completed, a channel error model was added to the protocol to permit the effects of channel errors to be measured. This error generation was used to test the effects of channel errors on Heartbeat and Token message passing. The C-language source code for the protocol modules was delivered to Goddard Space Flight Center for integration with the GSFC testbed. The need for a receiver autoconfiguration capability arises when a satellite-to-ground transmission is interrupted due to an unexpected event, the satellite transponder may reset to an unknown state and begin transmitting in a new mode. During Year 2, we completed testing of these algorithms when noise-induced bit errors were introduced. We also developed and tested an algorithm for estimating the data rate, assuming an NRZ-formatted signal corrupted with additive white Gaussian noise, and we took initial steps in integrating both algorithms into the SDR test bed at GSFC.

  9. Communications satellite no. 2 (CS-2)

    NASA Technical Reports Server (NTRS)

    1982-01-01

    The purpose of the Japanese CS-2 satellite is to provide national communications and industrial communications, such as special emergency and remote communications, and to contribute to the development of technology pertaining to communications satellites. Description and operating parameters of the following satellite components are presented: structure, communications system, telemetry/command system, electric power system, attitude and antenna control system, secondary propulsion system, apogee motor, framework, and heat control system.

  10. Trends in NASA communication satellites

    NASA Technical Reports Server (NTRS)

    Sivo, J. N.; Robbins, W. H.; Stretchberry, D. M.

    1972-01-01

    Satellite telecommunications can help to satisfy several national needs such as education, health care, cultural opportunities, and data transfer. There are current experiments being conducted with NASA spacecraft ATS 1, 3, and 5 in an attempt to satisfy these national needs. Future experiments are planned for the ATS F/G and CTS spacecrafts. The next generation of communications satellites must provide multiple region coverage, multichannel capability, high quality TV pictures, and must allow low cost ground receivers to be used. The proposed NASA spacecrafts, ATS H/I, will satisfy these requirements. Other countries of the world can benefit from ATS H/I technology.

  11. Spacecraft in switch matrix for wide band service applicatons in 30/20 GHz communications satellite systems

    NASA Technical Reports Server (NTRS)

    Cory, B. J.

    1982-01-01

    Bandwidth, switching speed, off-state isolation, and reliability over a ten-year mission were factors in determining the optimum available technology for satellite communications switching in 1982. A proof of concept model for a 20 x 20 coupled crossbar switch matrix designed with FET devices for microwave switching and with high speed CMOS LIS for switch crosspoint addressing was fabricated and tested. Results show the design is feasible for application in a multichannel SS-TDMA communications system. Expandibility can readily be achieved with this design. A conceptual design study for a 100 x 100 switch matrix utilizing a coupled crossbar architecture implemented with a monolithic microwave integrated circuits revealed technology needs for high capacity switch matrices.

  12. Modular approach for satellite communication ground terminals

    NASA Technical Reports Server (NTRS)

    Gould, G. R.

    1984-01-01

    The trend in satellite communications is toward completely digital, time division multiple access (TDMA) systems with uplink and downlink data rates dictated by the type of service offered. Trunking terminals will operate in the 550 MBPS (megabit per second) region uplink and downlink, whereas customer premise service (CPS) terminals will operate in the 25 to 10 MBPS region uplink and in the 200 MBPS region downlink. Additional criteria for the ground terminals will be to maintain clock sychronization with the system and burst time integrity to within a matter of nanoseconds, to process required order-fire information, to provide adaptive data scrambing, and to compensate for variations in the user input output data rates, and for changes in range in the satellite communications links resulting from satellite perturbations in orbit. To achieve the required adaptability of a ground terminal to the above mentioned variables, programmable building blocks can be developed that will meet all of these requirements. To maintain system synchronization, i.e., all bursted data arriving at the satellite within assigned TDMA windows, ground terminal transmit data rates and burst timing must be maintained within tight tolerances. With a programmable synchronizer as the heart of the terminal timing generation, variable data rates and burst timing tolerances are achievable. In essence, the unit inputs microprocessor generated timing words and outputs discrete timing pulses.

  13. Application of the Iridium Satellite System to Aeronautical Communications

    NASA Technical Reports Server (NTRS)

    Kerczewski, Robert J.; Meza, Mike; Gupta, Om

    2008-01-01

    The next generation air transportation system will require greater air-ground communications capacity to accommodate more air traffic with increased safety and efficiency. Communications will remain primarily terrestrially based, but satellite communications will have an increased role. Inmarsat s aeronautical services have been approved and are in use for aeronautical safety communications provided by geostationary satellites. More recently the approval process for the Iridium low earth orbit constellation is nearing completion. The current Iridium system will be able to provide basic air traffic services communications suitable for oceanic, remote and polar regions. The planned second generation of the Iridium system, called Iridium NEXT, will provide enhanced capabilities and enable a greater role in the future of aeronautical communications. This paper will review the potential role of satellite communications in the future of air transportation, the Iridium approval process and relevant system testing, and the potential role of Iridium NEXT.

  14. 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.

  15. Satellite-Based Quantum Communications

    SciTech Connect

    Hughes, Richard J; Nordholt, Jane E; McCabe, Kevin P; Newell, Raymond T; Peterson, Charles G

    2010-09-20

    Single-photon quantum communications (QC) offers the attractive feature of 'future proof', forward security rooted in the laws of quantum physics. Ground based quantum key distribution (QKD) experiments in optical fiber have attained transmission ranges in excess of 200km, but for larger distances we proposed a methodology for satellite-based QC. Over the past decade we have devised solutions to the technical challenges to satellite-to-ground QC, and we now have a clear concept for how space-based QC could be performed and potentially utilized within a trusted QKD network architecture. Functioning as a trusted QKD node, a QC satellite ('QC-sat') could deliver secret keys to the key stores of ground-based trusted QKD network nodes, to each of which multiple users are connected by optical fiber or free-space QC. A QC-sat could thereby extend quantum-secured connectivity to geographically disjoint domains, separated by continental or inter-continental distances. In this paper we describe our system concept that makes QC feasible with low-earth orbit (LEO) QC-sats (200-km-2,000-km altitude orbits), and the results of link modeling of expected performance. Using the architecture that we have developed, LEO satellite-to-ground QKD will be feasible with secret bit yields of several hundred 256-bit AES keys per contact. With multiple ground sites separated by {approx} 100km, mitigation of cloudiness over any single ground site would be possible, potentially allowing multiple contact opportunities each day. The essential next step is an experimental QC-sat. A number of LEO-platforms would be suitable, ranging from a dedicated, three-axis stabilized small satellite, to a secondary experiment on an imaging satellite. to the ISS. With one or more QC-sats, low-latency quantum-secured communications could then be provided to ground-based users on a global scale. Air-to-ground QC would also be possible.

  16. 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.

  17. The role of technology in influencing future civil communications satellites

    NASA Technical Reports Server (NTRS)

    Bagwell, James W.; Mahle, Christoph E.

    1990-01-01

    Technology, both as an enabler and as a driver of new and improved communication satellites, is discussed. A brief look at the beginnings and evolution of satellite communications is given to reveal the continuing influence of technology over the past 25 years. An assessment of the current state of the art which serves as a benchmark representing how far technology has come and as a basis for comparison for future possibilities is presented. A short tutorial on communications satellite basics is presented, followed by an assessment of technologies used for satellite antennas and signal amplification and routing. A discussion of future service requirements follows, and emerging technologies are identified along with possible improved communications capabilities that can result from them. The outlook for the role of technology for future communication satellites is summarized.

  18. Communications and media services

    NASA Technical Reports Server (NTRS)

    Mcculla, James W.; Kukowski, James F.

    1990-01-01

    NASA's internal and external communication methods are reviewed. NASA information services for the media, for the public, and for employees are discussed. Consideration is given to electron information distribution, the NASA TV-audio system, the NASA broadcast news service, astronaut appearances, technology and information exhibits, speaker services, and NASA news reports for internal communications. Also, the NASA worldwide electronic mail network is described and trends for future NASA communications and media services are outlined.

  19. The Impact of Satellites on Cable Communications.

    ERIC Educational Resources Information Center

    Chayes, Abram

    Two recent developments in communications satellite technology may speed the coming of cable TV (CATV) networks. First, increases in satellite power are reducing the cost of ground stations. Second, a connection between one ground station, the satellite, and any other ground station is no longer necessarily fixed. Now one station can communicate

  20. Information Delivery Through Broadcasting in Satellite Communication Networks

    E-print Network

    Tassiulas, Leandros

    Information Delivery Through Broadcasting in Satellite Communication Networks Leandros Tassiulas­range multicasting capability of satellites and the asymmetry of satellite communications (high bandwidth downlink. We consider a data broadcasting model that is encountered in most asymmetric satellite communication

  1. 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.

  2. Educational Applications of Communications Satellites in Canada. New Technologies in Canadian Education Series. Paper 12.

    ERIC Educational Resources Information Center

    Richmond, J. Murray

    Canada has explored the use of satellites as a means to provide information and communications services to geographically isolated populations since 1962. Between 1972 and 1984, five series of satellites known as Anik A, B, C, and D and Hermes were launched. Each satellite provided expanded communications services, and each led to research and…

  3. Internetworking satellite and local exchange networks for personal communications applications

    NASA Technical Reports Server (NTRS)

    Wolff, Richard S.; Pinck, Deborah

    1993-01-01

    The demand for personal communications services has shown unprecedented growth, and the next decade and beyond promise an era in which the needs for ubiquitous, transparent and personalized access to information will continue to expand in both scale and scope. The exchange of personalized information is growing from two-way voice to include data communications, electronic messaging and information services, image transfer, video, and interactive multimedia. The emergence of new land-based and satellite-based wireless networks illustrates the expanding scale and trend toward globalization and the need to establish new local exchange and exchange access services to meet the communications needs of people on the move. An important issue is to identify the roles that satellite networking can play in meeting these new communications needs. The unique capabilities of satellites, in providing coverage to large geographic areas, reaching widely dispersed users, for position location determination, and in offering broadcast and multicast services, can complement and extend the capabilities of terrestrial networks. As an initial step in exploring the opportunities afforded by the merger of satellite-based and land-based networks, several experiments utilizing the NASA ACTS satellite and the public switched local exchange network were undertaken to demonstrate the use of satellites in the delivery of personal communications services.

  4. Domestic satellite communications - The Canadian experience

    NASA Astrophysics Data System (ADS)

    Golden, D. A.

    1980-09-01

    The history of commercial satellite communications in Canada is surveyed. The benefits provided by the existing system are illustrated by focusing on the experience of a particular Arctic hamlet (Pangnirtung). Attention is given to the factors that have differentiated the Canadian system from the American one (smaller, less homogenous, and more widely dispersed population). The problem posed by 'pirate' earth stations in Canada is discussed. An account is given of the origin of the dual-band Anik B (6/4 GHz and 14/12 GHz channels) satellite series, and the experiments (telemedicine, tele-education, communication with remote communities) carried out with the Anik B are discussed. Attention is also given to the promising results obtained in the direct-to-home TV service delivered by Anik B. Plans for the Anik C (16 channels 14/12 GHz frequency band) and Anik D (24 channels 6/4 GHz frequency band) series are discussed. Canada's communications needs are such that the continued development of satellite systems seems assured.

  5. Design trade-offs in antijam military satellite communications

    NASA Astrophysics Data System (ADS)

    Brandon, W. T.

    1982-07-01

    Military satellite communications system technical parameters, boundary values and anti-jamming trade-offs among parameters are described and discussed. These systems, which have become essential elements of command, control and communication structures for the U.S., NATO and the Soviet Union, are characterized by such features as global connectivity of commanders and forces, and instant reconfiguration which allows a single system to support services as varied as broadcasting, point-to-point voice communication, and teletype data, for tactical, strategic or logistic users. Attention is given to the anti-jamming concept of satellite position uncertainty, in which a group of satellites functions as uplink receiver, and a single, larger satellite is used as a downlink transmitter. It is shown that, by constraining design to a finite number of satellite orbits, frequency bands and satellite and terminal designs, a practical number of about 5000 different system designs can be stipulated for further study.

  6. 47 CFR 25.148 - Licensing provisions for the Direct Broadcast Satellite Service.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... Satellite Service. 25.148 Section 25.148 Telecommunication FEDERAL COMMUNICATIONS COMMISSION (CONTINUED) COMMON CARRIER SERVICES SATELLITE COMMUNICATIONS Applications and Licenses Space Stations § 25.148 Licensing provisions for the Direct Broadcast Satellite Service. (a) License terms. License terms for...

  7. 47 CFR 25.148 - Licensing provisions for the Direct Broadcast Satellite Service.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... Satellite Service. 25.148 Section 25.148 Telecommunication FEDERAL COMMUNICATIONS COMMISSION (CONTINUED) COMMON CARRIER SERVICES SATELLITE COMMUNICATIONS Applications and Licenses Space Stations § 25.148 Licensing provisions for the Direct Broadcast Satellite Service. (a) License terms. License terms for...

  8. 47 CFR 25.210 - Technical requirements for space stations in the Fixed-Satellite Service.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... the Fixed-Satellite Service. 25.210 Section 25.210 Telecommunication FEDERAL COMMUNICATIONS COMMISSION (CONTINUED) COMMON CARRIER SERVICES SATELLITE COMMUNICATIONS Technical Standards § 25.210 Technical requirements for space stations in the Fixed-Satellite Service. (a) All space stations in the...

  9. 47 CFR 25.148 - Licensing provisions for the Direct Broadcast Satellite Service.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... Satellite Service. 25.148 Section 25.148 Telecommunication FEDERAL COMMUNICATIONS COMMISSION (CONTINUED) COMMON CARRIER SERVICES SATELLITE COMMUNICATIONS Applications and Licenses Space Stations § 25.148 Licensing provisions for the Direct Broadcast Satellite Service. (a) License terms. License terms for...

  10. 47 CFR 25.210 - Technical requirements for space stations in the Fixed-Satellite Service.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... the Fixed-Satellite Service. 25.210 Section 25.210 Telecommunication FEDERAL COMMUNICATIONS COMMISSION (CONTINUED) COMMON CARRIER SERVICES SATELLITE COMMUNICATIONS Technical Standards § 25.210 Technical requirements for space stations in the Fixed-Satellite Service. (a) All space stations in the...

  11. 47 CFR 25.215 - Technical requirements for space stations in the Direct Broadcast Satellite Service.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... the Direct Broadcast Satellite Service. 25.215 Section 25.215 Telecommunication FEDERAL COMMUNICATIONS COMMISSION (CONTINUED) COMMON CARRIER SERVICES SATELLITE COMMUNICATIONS Technical Standards § 25.215 Technical requirements for space stations in the Direct Broadcast Satellite Service. In addition to §...

  12. 47 CFR 25.215 - Technical requirements for space stations in the Direct Broadcast Satellite Service.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... the Direct Broadcast Satellite Service. 25.215 Section 25.215 Telecommunication FEDERAL COMMUNICATIONS COMMISSION (CONTINUED) COMMON CARRIER SERVICES SATELLITE COMMUNICATIONS Technical Standards § 25.215 Technical requirements for space stations in the Direct Broadcast Satellite Service. In addition to §...

  13. 47 CFR 25.215 - Technical requirements for space stations in the Direct Broadcast Satellite Service.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... the Direct Broadcast Satellite Service. 25.215 Section 25.215 Telecommunication FEDERAL COMMUNICATIONS COMMISSION (CONTINUED) COMMON CARRIER SERVICES SATELLITE COMMUNICATIONS Technical Standards § 25.215 Technical requirements for space stations in the Direct Broadcast Satellite Service. In addition to §...

  14. 47 CFR 25.148 - Licensing provisions for the Direct Broadcast Satellite Service.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... Satellite Service. 25.148 Section 25.148 Telecommunication FEDERAL COMMUNICATIONS COMMISSION (CONTINUED) COMMON CARRIER SERVICES SATELLITE COMMUNICATIONS Applications and Licenses Space Stations § 25.148 Licensing provisions for the Direct Broadcast Satellite Service. (a) License terms. License terms for...

  15. 47 CFR 25.148 - Licensing provisions for the Direct Broadcast Satellite Service.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... Satellite Service. 25.148 Section 25.148 Telecommunication FEDERAL COMMUNICATIONS COMMISSION (CONTINUED) COMMON CARRIER SERVICES SATELLITE COMMUNICATIONS Applications and Licenses Space Stations § 25.148 Licensing provisions for the Direct Broadcast Satellite Service. (a) License terms. License terms for...

  16. 47 CFR 25.210 - Technical requirements for space stations in the Fixed-Satellite Service.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... the Fixed-Satellite Service. 25.210 Section 25.210 Telecommunication FEDERAL COMMUNICATIONS COMMISSION (CONTINUED) COMMON CARRIER SERVICES SATELLITE COMMUNICATIONS Technical Standards § 25.210 Technical requirements for space stations in the Fixed-Satellite Service. (a) All space stations in the...

  17. 47 CFR 25.215 - Technical requirements for space stations in the Direct Broadcast Satellite Service.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... the Direct Broadcast Satellite Service. 25.215 Section 25.215 Telecommunication FEDERAL COMMUNICATIONS COMMISSION (CONTINUED) COMMON CARRIER SERVICES SATELLITE COMMUNICATIONS Technical Standards § 25.215 Technical requirements for space stations in the Direct Broadcast Satellite Service. In addition to §...

  18. 47 CFR 25.149 - Application requirements for ancillary terrestrial components in Mobile-Satellite Service...

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... terrestrial components in Mobile-Satellite Service networks operating in the 1.5./1.6 GHz and 1.6/2.4 GHz Mobile-Satellite Service. 25.149 Section 25.149 Telecommunication FEDERAL COMMUNICATIONS COMMISSION (CONTINUED) COMMON CARRIER SERVICES SATELLITE COMMUNICATIONS Applications and Licenses Space Stations §...

  19. Technology requirements for communication satellites in the 1980's

    NASA Technical Reports Server (NTRS)

    Burtt, J. E.; Moe, C. R.; Elms, R. V.; Delateur, L. A.; Sedlacek, W. C.; Younger, G. G.

    1973-01-01

    The key technology requirements are defined for meeting the forecasted demands for communication satellite services in the 1985 to 1995 time frame. Evaluation is made of needs for services and technical and functional requirements for providing services. The future growth capabilities of the terrestrial telephone network, cable television, and satellite networks are forecasted. The impact of spacecraft technology and booster performance and costs upon communication satellite costs are analyzed. Systems analysis techniques are used to determine functional requirements and the sensitivities of technology improvements for reducing the costs of meeting requirements. Recommended development plans and funding levels are presented, as well as the possible cost saving for communications satellites in the post 1985 era.

  20. Satellite communications systems and technology. Volume 2: Site reports

    NASA Technical Reports Server (NTRS)

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

    1993-01-01

    This is volume 2 of the final report of the NASA/NSF Panel on Satellite Communications Systems and Technology. It consists of the site reports from the panel's visits to satellite communications facilities and laboratories in Europe, Japan, and Russia. The Executive Summary of the panel's final report is published separately. Volume 1, also published separately, consists of the panel's analytical chapters. Information on ordering the Executive Summary and Volume 1 from the National Technical Information Service is included.

  1. Satellite services system analysis study. Volume 2: Satellite and services user model

    NASA Technical Reports Server (NTRS)

    1981-01-01

    Satellite services needs are analyzed. Topics include methodology: a satellite user model; representative servicing scenarios; potential service needs; manned, remote, and automated involvement; and inactive satellites/debris. Satellite and services user model development is considered. Groundrules and assumptions, servicing, events, and sensitivity analysis are included. Selection of references satellites is also discussed.

  2. A practical system for regional mobile satellite services

    NASA Technical Reports Server (NTRS)

    Glein, Randall; Leverson, Denis; Olmstead, Dean

    1993-01-01

    The Regional Mobile Satellite (MSAT) concept proposes a worldwide, interconnected mobile satellite service (MSS) network in which MSAT-type satellites provide the space segment services to separate regions (i.e., one or a few countries). Using this concept, mobile communications users across entire continents can now be served by a handful of regionally controlled satellites in geostationary earth orbit (GEO). All requirements, including hand-held telephone capabilities, can be cost-effectively provided using proven technologies. While other concepts of regional or global mobile communications continue to be explored, the Hughes Regional MSAT system demonstrates the near-term viability of the GEO approach.

  3. 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.

  4. A new antenna concept for satellite communications

    NASA Technical Reports Server (NTRS)

    Skahill, G.; Ciccolella, D.

    1982-01-01

    A novel antenna configuration of two reflecting surfaces and a phased array is examined for application to satellite communications and shown to be superior in every respect to earlier designs for service to the continental United States from synchronous orbit. The vignetting that afflicts other two reflector optical systems is eliminated by use of a reflecting field element. The remaining aberrations, predominantly coma, are isolated in the time delay distribution at the surface of the array and can be compensated by ordinary array techniques. The optics exhibits infinite bandwidth and the frequency range is limited only by the design of the array.

  5. Twenty years of international satellite communication

    NASA Astrophysics Data System (ADS)

    Evans, J. V.

    1986-08-01

    The development of satellite communications networks since 1957 is reviewed, and future trends are discussed. The emphasis is on commercial networks such as Comsat and Intelsat, and consideration is given to the early experimental satellites; the advantages of GEO satellites; the steady growth of the capabilities of satellite systems; advances in orbital injection and stationkeeping, stability and attitude control, and payload design; and communication-capacity improvements (increased bandwidths, shaped beams, TDMA, satellite-switched TDMA, and circuit multiplication). It is predicted that competition from undersea fiber-optic cables in the telephony market will shift the emphasis in satellite communications toward DBS-TV (especially in Europe), thin-route telephone and data communication using smaller earth stations, and mobile-station communication. Graphs, maps, photographs, and diagrams are provided.

  6. 48 CFR 252.225-7049 - Prohibition on Acquisition of Commercial Satellite Services From Certain Foreign Entities...

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ...Prohibition on Acquisition of Commercial Satellite Services From Certain Foreign Entities...or instrumentality thereof. Satellite services means communications capabilities that utilize an on-orbit satellite for transmitting the signal...

  7. Interim Service ISDN Satellite (ISIS) hardware experiment design for advanced ISDN satellite design and experiments

    NASA Technical Reports Server (NTRS)

    Pepin, Gerard R.

    1992-01-01

    The Interim Service Integrated Services Digital Network (ISDN) Satellite (ISIS) Hardware Experiment Design for Advanced Satellite Designs describes the design of the ISDN Satellite Terminal Adapter (ISTA) capable of translating ISDN protocol traffic into time division multiple access (TDMA) signals for use by a communications satellite. The ISTA connects the Type 1 Network Termination (NT1) via the U-interface on the line termination side of the CPE to the V.35 interface for satellite uplink. The same ISTA converts in the opposite direction the V.35 to U-interface data with a simple switch setting.

  8. Interim Service ISDN Satellite (ISIS) hardware experiment development for advanced ISDN satellite designs and experiments

    NASA Technical Reports Server (NTRS)

    Pepin, Gerard R.

    1992-01-01

    The Interim Service Integrated Service Digital Network (ISDN) Satellite (ISIS) Hardware Experiment Development for Advanced Satellite Designs describes the development of the ISDN Satellite Terminal Adapter (ISTA) capable of translating ISDN protocol traffic into Time Division Multiple Access (TDMA) signals for use by a communications satellite. The ISTA connects the Type 1 Network Termination (NT1) via the U-interface on the line termination side of the CPE to the RS-499 interface for satellite uplink. The same ISTA converts in the opposite direction the RS-499 to U-interface data with a simple switch setting.

  9. Commercialization of Advanced Communications Technology Satellite (ACTS) technology

    NASA Astrophysics Data System (ADS)

    Plecity, Mark S.; Strickler, Walter M.; Bauer, Robert A.

    1996-03-01

    In an on-going effort to maintain United States leadership in communication satellite technology, the National Aeronautics and Space Administration (NASA), led the development of the Advanced Communications Technology Satellite (ACTS). NASA's ACTS program provides industry, academia, and government agencies the opportunity to perform both technology and telecommunication service experiments with a leading-edge communication satellite system. Over 80 organizations are using ACTS as a multi server test bed to establish communication technologies and services of the future. ACTS was designed to provide demand assigned multiple access (DAMA) digital communications with a minimum switchable circuit bandwidth of 64 Kbps, and a maximum channel bandwidth of 900 MHZ. It can, therefore, provide service to thin routes as well as connect fiber backbones in supercomputer networks, across oceans, or restore full communications in the event of national or manmade disaster. Service can also be provided to terrestrial and airborne mobile users. Commercial applications of ACTS technologies include: telemedicine; distance education; Department of Defense operations; mobile communications, aeronautical applications, terrestrial applications, and disaster recovery. This paper briefly describes the ACTS system and the enabling technologies employed by ACTS including Ka-band hopping spot beams, on-board routing and switching, and rain fade compensation. When used in conjunction with a time division multiple access (TDMA) architecture, these technologies provide a higher capacity, lower cost satellite system. Furthermore, examples of completed user experiments, future experiments, and plans of organizations to commercialize ACTS technology in their own future offerings will be discussed.

  10. Engineering calculations for communications satellite systems planning

    NASA Technical Reports Server (NTRS)

    Reilly, C. H.; Levis, C. A.; Mount-Campbell, C.; Gonsalvez, D. J.; Wang, C. W.; Yamamura, Y.

    1985-01-01

    Computer-based techniques for optimizing communications-satellite orbit and frequency assignments are discussed. A gradient-search code was tested against a BSS scenario derived from the RARC-83 data. Improvement was obtained, but each iteration requires about 50 minutes of IBM-3081 CPU time. Gradient-search experiments on a small FSS test problem, consisting of a single service area served by 8 satellites, showed quickest convergence when the satellites were all initially placed near the center of the available orbital arc with moderate spacing. A transformation technique is proposed for investigating the surface topography of the objective function used in the gradient-search method. A new synthesis approach is based on transforming single-entry interference constraints into corresponding constraints on satellite spacings. These constraints are used with linear objective functions to formulate the co-channel orbital assignment task as a linear-programming (LP) problem or mixed integer programming (MIP) problem. Globally optimal solutions are always found with the MIP problems, but not necessarily with the LP problems. The MIP solutions can be used to evaluate the quality of the LP solutions. The initial results are very encouraging.

  11. An overview of the OmniTRACS: The first operational mobile Ku-band satellite communications

    NASA Technical Reports Server (NTRS)

    Salmasi, Allen

    1988-01-01

    The service features of the OmniTRACS system developed by Omninet Communications Services of Los Angeles, California are described. This system is the first operational mobile Ku-band satellite communications system that provides two-way messaging and position determination and reporting services to mobile users on a nationwide basis. The system uses existing Ku-band satellites under a secondary international allocation for mobile satellite services.

  12. NASA Compendium of Satellite Communications Programs

    NASA Technical Reports Server (NTRS)

    1973-01-01

    A comprehensive review is presented of worldwide communication programs that range in time from the inception of satellite communications to August 1971. The programs included are: Echo, Courier, West Ford, Telstar, Relay, Syncom, Lincoln experimental satellites, Intelsat, Tacsat, Skynet, Nato system, and Telesat.

  13. Dimensioning of Aeronautical Satellite Services

    NASA Astrophysics Data System (ADS)

    Holzbock, M.; Jahn, A.; Werner, M.

    2002-01-01

    This paper will provide a generalised baseline for a systematic AirCom design process and address in particular the dimensioning of satellite systems for aeronautical services. These services will roll out soon in medium- and long-haul aircraft. The offered services will range from low rate telephony, internet access, and streaming applications for video and audio. The aggregate bit rates on up- and downlink will certainly be statistically time-dependent and asymmetric in forward and backward direction. A tool will be described that is able to model this traffic. Furthermore the dimensioning of satellite constellations can be done. Due to the stochastic nature of the traffic, multi-service models for the traffic generation of different services will be described. Furthermore, the traffic will be affected by the available bit rate and shaping or blocking will equalize the peak loads. If fleets with many aircraft are considered, aeronautical traffic models must be based on actual aircraft routes, flight schedules, location and time of day, as well as seats per aircraft and type of aircraft (charter, business etc.). The regionally distributed traffic has to be served by several satellites and appropriate sharing of the serving satellites may spread the traffic in hot zones and yield a better load distribution. When aeronautical services will spread out, the capacity demand will grow quickly and the capacity of existing Ku-band GEO satellites will soon be exceeded. Changing to higher frequency bands will provide large spectrum portions and smaller spotbeams will allow better frequency reuse. Even constellations with non-geostationary satellites could be re-advent to serve better the higher latitude regions. Then, another mobility component for the fast changing satellite topology need to be addressed, and routing issues of the traffic must be considered. The paper will describe solutions for the mapping of satellites and traffic demand as well as routing algorithms. Numerical values will show the capabilities of the developed tool by calculating the performance of some selected scenarios. The paper will also address wireless cabin services (cell phones and W-LAN access for laptops) of the WirelessCabin project.

  14. Satellite Products and Services Review Board ATBD: Satellite-Derived

    E-print Network

    Miami, University of

    Satellite Products and Services Review Board ATBD: Satellite-Derived Ocean Heat Content Version 1.0 July 2012 ___________________________________ #12;NOAA /RSMAS ATBD : Satellite-Derived Ocean Heat/STAR) #12;NOAA /RSMAS ATBD : Satellite-Derived Ocean Heat Content Product Page 3 of 32 TABLE OF CONTENTS

  15. A new phase for NASA's communications satellite program

    NASA Technical Reports Server (NTRS)

    Dement, D. K.

    1980-01-01

    NASA's research in communications satellite technology is discussed, including orbit-efficient techniques and applications by the commercial sector. Attention is given to expanding the capacities of the C-band (6-4 GHz) and the Ku-band (14-11 GHz), opening the Ka-band (30/20 GHz), broadly applied 're-use' of the spectrum, and developing multibeam spacecraft antennas with on-board switching. Increasing wideband services in video, high-speed data, and voice trunking is considered, as are narrow-band systems that may be used for data collection or public safety, with possible expansion to a thin-route satellite system. In particular, communication for medical, disaster, or search-and-rescue emergencies may be met by the integration of a satellite service with land mobile communications via terrestrial radio links. Also considered is a large geostationary platform providing electrical power, thermal rejection, and orbital station-keeping for many communications payloads.

  16. Resource allocation and scheduling for communication satellites with advanced transmission antennas

    E-print Network

    Choi, Jihwan Patrick, 1975-

    2006-01-01

    For multimedia and other data services over satellite networks, the efficient management of scarce satellite communication resources is critical for the economic competitiveness of the medium. To support a broad spectrum ...

  17. Perspectives on European satellite communications

    NASA Astrophysics Data System (ADS)

    Weber, H.

    1984-09-01

    The Intelsat System is the classic intercontinental transmission system for television signals and large FDM beams is outlined. An important medium for the transmission of small beams and of individual telephone communication traffic. With its satellites of continuously increasing size and complexity the fifth generation is now in operation, the sixth in development it provides the following capacities in several areas of its radiation: the 6/4-GHz range (C band) and the 14/11-GHz range (Ku band). The prevailing transmission technology in the Intelsat System was analog, however changeover to digital transmission technology with pulse code modulation (PCM) as source coding and using time division multiple access (TDMA), has commenced with the construction of the ground stations.

  18. Satellite services handbook. Interface guidelines

    NASA Astrophysics Data System (ADS)

    1983-12-01

    Satellite interfaces for on orbit servicing, both manned and unmanned are identified, and is intended to be used by designers of space vehicles, both foreign and domestic. A primary concern is for design of interfaces with the astronaut in the loop, especially extravehicular activity, but also intravehicular activity and operations that are remote but have man-in-the-loop. The main emphasis is on servicing in low earth orbits from the Space Shuttle and also from the Space Station or other platforms.

  19. NASA compendium of satellite communications programs

    NASA Technical Reports Server (NTRS)

    1975-01-01

    A comprehensive review is given of worldwide satellite communication programs that range in time from the inception of satellite communications to mid-1974. Particular emphasis is placed on program results, including experiments conducted, communications system operational performance, and technology employed. The background for understanding these results is established through brief summaries of the program organization, system configuration, and satellite and ground terminal characteristics. Major consideration is given to the communications system aspects of each program, but general spacecraft technology and other experiments conducted as part of the same program are mentioned summarily.

  20. The Mobile Satellite Services Market.

    ERIC Educational Resources Information Center

    Anderson, Samuel

    Mobile satellite (MSAT) technology is the basis for a new component of the telecommunications industry capable of providing services to small inexpensive subscriber terminals located almost any place in the world. The market for MSAT space segment capacity (bandwidth and power) is a natural monopoly that can be logically and technically…

  1. Broadcast satellite service: The international dimension

    NASA Technical Reports Server (NTRS)

    Samara, Noah

    1991-01-01

    The dawn of the 1990's has witnessed the birth of a new satellite service - satellite sound broadcasting. This new service is characterized by digital transmission at data rates up to 256 kb/s from satellites in geostationary orbit to small, low-cost, mobile and portable receivers. The satellite sound broadcasting service is a logical step beyond navigation satellite service, such as that provided by the GPS Navstar system. The mass market appeal of satellite sound broadcasting in the area of lightsat technology and low-cost digital radios has greatly facilitated the financing of this type of space service.

  2. Satellite-aided mobile communications, experiments, applications and prospects

    NASA Technical Reports Server (NTRS)

    Anderson, R. E.; Frey, R. L.; Lewis, J. R.; Milton, R. T.

    1980-01-01

    NASA's ATS-series of satellites were used in a series of communications and position fixing experiments with automotive vehicles, ships and aircraft. Applications of the communications were demonstrated and evaluated for public services including law enforcement, search and rescue, and medical emergency, and for commercial uses in the land and maritime transportation industries. The technical success of the experiments and the demonstrated potential value of the communications prompted a study that concluded an operational satellite-aided system would be a valuable augmentation of planned trunking or cellular type terrestrial mobile radio telephone systems.

  3. NASA's Advanced Communications Technology Satellite (ACTS)

    NASA Technical Reports Server (NTRS)

    Gedney, R. T.

    1983-01-01

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

  4. A personal communications network using a Ka-band satellite

    NASA Technical Reports Server (NTRS)

    Palmer, L. C.; Stern, A.; Sohn, P. Y.

    1991-01-01

    The feasibility of portable communications terminals that can provide 4.8-kbps voice communications to a hub station via a Ka-band geosynchronous satellite was investigated. Tradeoffs are examined so that the combined system of the hub and gateway earth stations, the satellite, and the personal terminals can provide a competitive service in terms of cost, availability, and quality. A baseline system is described using a spacecraft with approximately 140 spot beams that cover CONUS with 5-watt power amplifiers in each beam. Satellite access in both the forward and return directions uses Frequency Division Multiple Access/Code Division Multiple Access (FDMA/CDMA) with a chip rate of 2.5 Mchip/sec. An experiment is recommended using the Advanced Communications Technology Satellite (ACTS) to demonstrate some of the features of the portable terminal concept.

  5. 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 arrives at a schedule of costs and payments for all the items and the years in which they will be incurred. The second category of costing problems is one of financing or engineering economics. All the costs are first "present valued" to some reference period using rates of return appropriate to the particular situation. One finally arrives at sets of annual costs which can be used as the basis for setting lease costs or revenue requirements and tariffs. The correspondence between methods using discounted rates of return and capital recovery formulae on one hand and those using various depreciation schedules, such as is typical of regulated industries on the other hand, is discussed. The remainder of the paper is devoted to discussing the relationship between critical parameters, such as replacement schedules, design lifetime, satellite power and Earth station antenna size, and the overall costs. It is shown that optima for these parameters may exist and can be calculated. In particular, the optimization of satellite replacement schedules to minimize the present value of total investment over a very long period is presented, along with simplified versions of the theory suitable for system planning. The choice of EIRP is also discussed and a procedure for choosing the value that minimizes the costs is shown.

  6. Spacecraft Modularity for Serviceable Satellites

    NASA Technical Reports Server (NTRS)

    Reed, Benjamin B.; Rossetti, Dino; Keer, Beth; Panek, John; Cepollina, Frank; Ritter, Robert

    2015-01-01

    Spacecraft modularity has been a topic of interest at NASA since the 1970s, when the Multi-Mission Modular Spacecraft (MMS) was developed at the Goddard Space Flight Center. Since then, modular concepts have been employed for a variety of spacecraft and, as in the case of the Hubble Space Telescope (HST) and the International Space Station (ISS), have been critical to the success of on-orbit servicing. Modularity is even more important for future robotic servicing. Robotic satellite servicing technologies under development by NASA can extend mission life and reduce life-cycle cost and risk. These are optimized when the target spacecraft is designed for servicing, including advanced modularity. This paper will explore how spacecraft design, as demonstrated by the Reconfigurable Operational spacecraft for Science and Exploration (ROSE) spacecraft architecture, and servicing technologies can be developed in parallel to fully take advantage of the promise of both.

  7. Spacecraft Modularity for Serviceable Satellites

    NASA Technical Reports Server (NTRS)

    Rossetti, Dino; Keer, Beth; Panek, John; Ritter, Bob; Reed, Benjamin; Cepollina, Frank

    2015-01-01

    Spacecraft modularity has been a topic of interest at NASA since the 1970s, when the Multi-­-Mission Modular Spacecraft (MMS) was developed at the Goddard Space Flight Center. Since then, modular concepts have been employed for a variety of spacecraft and, as in the case of the Hubble Space Telescope (HST) and the International Space Station (ISS), have been critical to the success of on-­- orbit servicing. Modularity is even more important for future robotic servicing. Robotic satellite servicing technologies under development by NASA can extend mission life and reduce lifecycle cost and risk. These are optimized when the target spacecraft is designed for servicing, including advanced modularity. This paper will explore how spacecraft design, as demonstrated by the Reconfigurable Operational spacecraft for Science and Exploration (ROSE) spacecraft architecture, and servicing technologies can be developed in parallel to fully take advantage of the promise of both.

  8. Program on application of communications satellites to educational development

    NASA Technical Reports Server (NTRS)

    Morgan, R. P.; Singh, J. P.

    1971-01-01

    Interdisciplinary research in needs analysis, communications technology studies, and systems synthesis is reported. Existing and planned educational telecommunications services are studied and library utilization of telecommunications is described. Preliminary estimates are presented of ranges of utilization of educational telecommunications services for 1975 and 1985; instructional and public television, computer-aided instruction, computing resources, and information resource sharing for various educational levels and purposes. Communications technology studies include transmission schemes for still-picture television, use of Gunn effect devices, and TV receiver front ends for direct satellite reception at 12 GHz. Two major studies in the systems synthesis project concern (1) organizational and administrative aspects of a large-scale instructional satellite system to be used with schools and (2) an analysis of future development of instructional television, with emphasis on the use of video tape recorders and cable television. A communications satellite system synthesis program developed for NASA is now operational on the university IBM 360-50 computer.

  9. Engineering calculations for communications satellite systems planning

    NASA Technical Reports Server (NTRS)

    Levis, C. A.; Martin, C. H.; Reilly, C. H.; Gonsalvez, D. J.; Yamaura, Y.

    1985-01-01

    An extended gradient search code for broadcasting satellite service (BSS) spectrum/orbit assignment synthesis is discussed. Progress is also reported on both single-entry and full synthesis computational aids for fixed satellite service (FSS) spectrum/orbit assignment purposes.

  10. Overview of the Anik C satellites and services

    NASA Astrophysics Data System (ADS)

    Smart, F. H.

    An overview of the important technical characteristics of the Anik C series of Canadian communications satellites is presented. The system was launched as part of the Telesat Communications payload of the Space Shuttle in 1982. Among the services the system will in the near future provide are: a 27 MHz channel bandwidth television service for pay-TV distribution in Canada; two TV channels for hockey broadcasts and a transportable TV system; a heavy-voice route telephone service for five major Canadian cities; and a telephone system for business voice and data communications. Services anticipated for Anik-C satellites later in the decade include a Single Channel Per Carrier (SCPC) voice and data communications system for British Columbia and the Maritime Provinces, and a direct-to-home broadcast service to be sold to television markets in the United States.

  11. 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.

  12. 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.

  13. Satellite servicing: A business opportunity?

    NASA Technical Reports Server (NTRS)

    Wong, R. E.; Medler, E. H.

    1984-01-01

    The possibilities of satellite servicing as a business opportunity are examined. The service rate which a user must be charged to yield a reasonable return is derived and then compared against the market's willingness to pay that rate. Steps taken to provide the basis from which the service rate could be derived include: (1) constructing a hypothetical on orbit servicing business offering both on orbit and associated ground services; (2) estimating the total on orbit service business potential by analyzing mission models to the year 2000; and (3) setting up ground rules to bound the conduct of the business. Using this basic information service demand (business volume) cost to set up the business, costs for operation and maintenance tax rates and desired rate of return are estimated to determine the user charge. Sensitivity of the service rate to various parameters are also assessed. The time span for the business venture runs from 1986 through 2000 with service to 1991 provided via the orbiter and by a space station beyond 1991. This point analysis shows about five years of negative cash flow, with steady profits thereafter.

  14. Land Mobile Satellite Service (LMSS) channel simulator: An end-to-end hardware simulation and study of the LMSS communications links

    NASA Technical Reports Server (NTRS)

    Salmasi, A. B. (editor); Springett, J. C.; Sumida, J. T.; Richter, P. H.

    1984-01-01

    The design and implementation of the Land Mobile Satellite Service (LMSS) channel simulator as a facility for an end to end hardware simulation of the LMSS communications links, primarily with the mobile terminal is described. A number of studies are reported which show the applications of the channel simulator as a facility for validation and assessment of the LMSS design requirements and capabilities by performing quantitative measurements and qualitative audio evaluations for various link design parameters and channel impairments under simulated LMSS operating conditions. As a first application, the LMSS channel simulator was used in the evaluation of a system based on the voice processing and modulation (e.g., NBFM with 30 kHz of channel spacing and a 2 kHz rms frequency deviation for average talkers) selected for the Bell System's Advanced Mobile Phone Service (AMPS). The various details of the hardware design, qualitative audio evaluation techniques, signal to channel impairment measurement techniques, the justifications for criteria of different parameter selection in regards to the voice processing and modulation methods, and the results of a number of parametric studies are further described.

  15. The use of satellites in non-goestationary orbits for unloading geostationary communication satellite traffic peaks. Volume 2: Technical report

    NASA Technical Reports Server (NTRS)

    Price, K.; Turner, A.; Nguyen, T.; Doong, W.; Weyandt, C.

    1987-01-01

    The part of the geostationary (GEO) orbital arc used for United States domestic fixed, communications service is rapidly becoming filled with satellites. One of the factors currently limiting its utilization is that communications satellites must be designed to have sufficient capacity to handle peak traffic leads, and thus are under utilized most of the time. A solution is to use satellites in suitable non-geostationary orbits to unload the traffic peaks. Three different designs for a non-geostationary orbit communications satellite system are presented for the 1995 time frame. The economic performance is analyzed and compared with geostationary satellites for two classes of service, trunking and customer premise service. The result is that the larger payload of the non-geostationary satellite offsets the burdens of increased complexity and worse radiation environment to give improved economic performance. Depending on ground terminal configuration, the improved economic performance of the space segment may be offset by increased ground terminal expenses.

  16. Communication Capacity Optimization for Broadband Satellite Communication Systems

    NASA Astrophysics Data System (ADS)

    Nakasuga, Yoshinori; Mitsugi, Jin; Ueba, Masazumi; Mizuno, Hideki

    2002-01-01

    ground-based access systems, such as FTTH, ADSL and even terrestrial cellular systems, are only available within limited geographical areas, broadband satellite communication systems that can cover unlimited service area have attracted wide interest. However, the success of broadband satellite communication depends heavily on the cost of user terminals and satellite circuits. and frequency bandwidth, which involves design parameters. For such parameters, we must consider modulation, coding, the number of radiating beams and the number of areas in which frequency bandwidth can be reused. These parameters should be chosen such that maximum communication capacity can be provided with minimum system resources under a designated rain attenuation and interference environment. The difficulty in optimization stems from the number of design parameters and the interactions between them. The optimization also has to be done in a manner such that the service provider can determine the relation between the service cost and the service grade. The service grade can be expressed in terms of the available user information rate, return link as well as forward link, and the number of available communication channels, while the system cost can be expressed in terms of required satellite power and the bandwidth. power and bandwidth parameters. In the method, the number of spot beams, the number of repeated bandwidth areas and the type of modulation are separately determined for the return and forward link. From the selected design parameters, the relationship between bandwidth capacity and power capacity is derived assuming they are linear. The power and bandwidth required for the return and forward link are then integrated by applying a linear programming method. The constraints in linear programming are power and bandwidth. To denote the system resource management proficiency, we introduce an index called power-utilization efficiency, which is a ratio of the maximum capacity to the required power. systems that have 15 or 35 spot beams. Since circuit quality degradation in Ku band systems due to the propagation environments is less than that in Ka band systems, the power-utilization efficiency of the Ku band is 1.25 times more that of the Ka band. On the other hand, the total capacity of the Ka band is 3.5 times that of the Ku band since the allocated bandwidth in the Ku band is narrower than that of the Ka band. Bandwidth reuse is an effective way to increase total available bandwidth. For the same service area and the same number of reused bandwidths, increasing the number of spot beams can reduce the interference between different areas assigned the same frequency, since the distance between those areas widens. This enables total capacity and power-utilization efficiency for a 35-spot-beam system to be more than 2.2 and 2.75 times greater, respectively, than for a 15-spot-beam system. limited transmission power of the user terminal. Therefore, the return link transponder requires a higher transmission power level to compensate for this limitation. On the other hand, a high-quality downlink is also required for the forward link because of the small size of the user terminal antenna. However, the quality of the forward link can be maintained since it is possible to increase uplink quality by improving hub-station performance. This makes it possible to suppress the increase in the transmission power of the forward link transponder in comparison with that of the return link transponder. As an example, we compared two cases, in one of which the capacity ratio (forward link capacity divided by the return link capacity) was 2.0 and in the other of which it was 10.0. We found that the amount of capacity and power utilization efficiency were, respectively, 33% and 50% greater for the latter case than for the former case. applications.

  17. Satellite fixed communications service: A forecast of potential domestic demand through the year 2000. Volume 3: Appendices

    NASA Technical Reports Server (NTRS)

    Kratochvil, D.; Bowyer, J.; Bhushan, C.; Steinnagel, K.; Kaushal, D.; Al-Kinani, G.

    1983-01-01

    Voice applications, data applications, video applications, impacted baseline forecasts, market distribution model, net long haul forecasts, trunking earth station definition and costs, trunking space segment cost, trunking entrance/exit links, trunking network costs and crossover distances with terrestrial tariffs, net addressable forecasts, capacity requirements, improving spectrum utilization, satellite system market development, and the 30/20 net accessible market are considered.

  18. Communication satellites: Guidelines for a strategic plan

    NASA Technical Reports Server (NTRS)

    1987-01-01

    To maintain and augment the leadership that the United States has enjoyed and to ensure that the nation is investing sufficiently and wisely to this purpose, a strategic plan for satellite communications research and development was prepared by NASA. Guidelines and recommendations for a NASA plan to support this objective and for the conduct of communication satellite research and development program over the next 25 years were generated. The guidelines are briefly summarized.

  19. Large communications platforms versus smaller satellites

    NASA Technical Reports Server (NTRS)

    1979-01-01

    Communications systems using large platforms are compared with systems using conventional satellites. Systems models were generated and compared for U.S. domestic application and for 1 INTELSAT's international and domestic transponder lease application. Technology advances were assumed the platforms and the evolution of conventional satellites.

  20. Sharing Resources In Mobile/Satellite Communications

    NASA Technical Reports Server (NTRS)

    Yan, Tsun-Yee; Sue, Miles K.

    1992-01-01

    Report presents preliminary theoretical analysis of several alternative schemes for allocation of satellite resource among terrestrial subscribers of landmobile/satellite communication system. Demand-access and random-access approaches under code-division and frequency-division concepts compared.

  1. The Arctic Regional Communications Small SATellite (ARCSAT)

    NASA Technical Reports Server (NTRS)

    Casas, Joseph; Kress, Martin; Sims, William; Spehn, Stephen; Jaeger, Talbot; Sanders, Devon

    2013-01-01

    Traditional satellite missions are extremely complex and expensive to design, build, test, launch and operate. Consequently many complementary operational, exploration and research satellite missions are being formulated as a growing part of the future space community capabilities using formations of small, distributed, simple to launch and inexpensive highly capable small scale satellites. The Arctic Regional Communications small SATellite (ARCSAT) initiative would launch a Mini-Satellite "Mothership" into Polar or Sun Sync low-earth-orbit (LEO). Once on orbit, the Mothership would perform orbital insertion of four internally stored independently maneuverable nanosatellites, each containing electronically steerable antennas and reconfigurable software-defined radios. Unlike the traditional geostationary larger complex satellite communication systems, this LEO communications system will be comprised of initially a five small satellite formation that can be later incrementally increased in the total number of satellites for additional data coverage. ARCSAT will provide significant enabling capabilities in the Arctic for autonomous voice and data communications relay, Maritime Domain Awareness (MDA), data-extraction from unattended sensors, and terrestrial Search & Rescue (SAR) beacon detection missions throughout the "data starved desert" of the Arctic Region.

  2. Satellite Communication and Development: A Reassessment.

    ERIC Educational Resources Information Center

    Hudson, Heather E.

    The potential benefits of satellite communications development have been recognized since the notion of a geostationary "space platform" was proposed by Arthur C. Clarke in 1945. Although there have been examples of developmental applications of satellite technology, the promise has been slow in being fulfilled. The history of the application of…

  3. Introduction to Satellite Communications Technology for NREN

    NASA Technical Reports Server (NTRS)

    Stone, Thom

    2004-01-01

    NREN requirements for development of seamless nomadic networks necessitates that NREN staff have a working knowledge of basic satellite technology. This paper addresses the components required for a satellite-based communications system, applications, technology trends, orbits, and spectrum, and hopefully will afford the reader an end-to-end picture of this important technology.

  4. Narrow-Band Applications of Communications Satellites.

    ERIC Educational Resources Information Center

    Cowlan, Bert; Horowitz, Andrew

    This paper attempts to describe the advantages of "narrow-band" applications of communications satellites for education. It begins by discussing the general controversy surrounding the use of satellites in education, by placing the concern within the larger context of the general debate over the uses of new technologies in education, and by…

  5. Spacecraft Modularity for Serviceable Satellites

    NASA Technical Reports Server (NTRS)

    Rossetti, Dino; Keer, Beth; Panek, John; Reed, Benjamin; Cepollina, Frank; Ritter, Robert

    2015-01-01

    Satellite servicing has been a proven capability of NASA since the first servicing missions in the 1980s with astronauts on the space shuttle. This capability enabled the on-orbit assembly of the International Space Station (ISS) and saved the Hubble Space Telescope (HST) mission following the discovery of the flawed primary mirror. The effectiveness and scope of servicing opportunities, especially using robotic servicers, is a function of how cooperative a spacecraft is. In this paper, modularity will be presented as a critical design aspect for a spacecraft that is cooperative from a servicing perspective. Different features of modularity are discussed using examples from HST and the Multimission Modular Spacecraft (MMS) program from the 1980s and 1990s. The benefits of modularity will be presented including those directly related to servicing and those outside of servicing including reduced costs and increased flexibility. The new Reconfigurable Operational spacecraft for Science and Exploration (ROSE) concept is introduced as an affordable implementation of modularity that provides cost savings and flexibility. Key aspects of the ROSE architecture are discussed such as the module design and the distributed avionics architecture. The ROSE concept builds on the experience from MMS and due to its modularity, would be highly suitable as a future client for on-orbit servicing.

  6. Explanatory information for news conference on satellite communications

    NASA Technical Reports Server (NTRS)

    1983-01-01

    The CS-2 communications satellite which has features such as frequencies of the 30/20GHz band, demand assign time division multiple access, improved ship-to-satellite communications methods, and multibeam satellite communications methods. Research is continuing towards the production of larger, more economical communication systems via satellite which have greater efficiency and capacity.

  7. Soviet satellite communications science and technology

    SciTech Connect

    Birch, J.N.; Campanella, S.J.; Gordon, G.D.; McElroy, D.R.; Pritchard, W.L.; Stamminger, R.

    1991-08-01

    This is a report by six US scientists and engineers concerning the current state of the art and projections of future Soviet satellite communications technologies. The panel members are experts in satellite stabilization, spacecraft environments, space power generation, launch systems, spacecraft communications sciences and technologies, onboard processing, ground stations, and other technologies that impact communications. The panel assessed the Soviet ability to support high-data-rate space missions at 128 Mbps by evaluating current and projected Soviet satellite communications technologies. A variety of space missions were considered, including Earth-to-Earth communications via satellites in geostationary or highly elliptical orbits, those missions that require space-to-Earth communications via a direct path and those missions that require space-to-Earth communications via a relay satellite. Soviet satellite communications capability, in most cases, is 10 years behind that of the United States and other industrialized nations. However, based upon an analysis of communications links needed to support these missions using current Soviet capabilities, it is well within the current Soviet technology to support certain space missions outlined above at rates of 128 Mbps or higher, although published literature clearly shows that the Soviet Union has not exceeded 60 Mbps in its current space system. These analyses are necessary but not sufficient to determine mission data rates, and other technologies such as onboard processing and storage could limit the mission data rate well below that which could actually be supported via the communications links. Presently, the Soviet Union appears to be content with data rates in the low-Earth-orbit relay via geostationary mode of 12 Mbps. This limit is a direct result of power amplifier limits, spacecraft antenna size, and the utilization of K{sub u}-band frequencies. 91 refs., 16 figs., 15 tabs.

  8. Satellite utilization for educational communications in the U.S.

    NASA Technical Reports Server (NTRS)

    Morgan, R. P.; Singh, J. P.

    1974-01-01

    This paper summarizes completed, continuing and planned satellite experiments in the U.S. related to the delivery of educational services and networking. It also describes some results of an on-going study at Washington University directed towards defining applications of fixed/broadcast communication satellites in the U.S. and alternative systems and strategies for large-scale telecommunication-based educational delivery systems utilizing satellites. An analysis is presented of recent actions which may influence future development of such systems.

  9. 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.

  10. 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.

  11. 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.

  12. 47 CFR 25.142 - Licensing provisions for the non-voice, non-geostationary Mobile-Satellite Service.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ...-geostationary Mobile-Satellite Service. 25.142 Section 25.142 Telecommunication FEDERAL COMMUNICATIONS COMMISSION (CONTINUED) COMMON CARRIER SERVICES SATELLITE COMMUNICATIONS Applications and Licenses Space Stations § 25.142 Licensing provisions for the non-voice, non-geostationary Mobile-Satellite Service....

  13. 47 CFR 25.142 - Licensing provisions for the non-voice, non-geostationary mobile-satellite service.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ...-geostationary mobile-satellite service. 25.142 Section 25.142 Telecommunication FEDERAL COMMUNICATIONS COMMISSION (CONTINUED) COMMON CARRIER SERVICES SATELLITE COMMUNICATIONS Applications and Licenses Space Stations § 25.142 Licensing provisions for the non-voice, non-geostationary mobile-satellite service....

  14. 47 CFR 25.149 - Application requirements for ancillary terrestrial components in the mobile-satellite service...

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... terrestrial components in the mobile-satellite service networks operating in the 1.5./1.6 GHz, 1.6/2.4 GHz and 2 GHz mobile-satellite service. 25.149 Section 25.149 Telecommunication FEDERAL COMMUNICATIONS COMMISSION (CONTINUED) COMMON CARRIER SERVICES SATELLITE COMMUNICATIONS Applications and Licenses...

  15. 47 CFR 25.149 - Application requirements for ancillary terrestrial components in the mobile-satellite service...

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... terrestrial components in the mobile-satellite service networks operating in the 1.5./1.6 GHz, 1.6/2.4 GHz and 2 GHz mobile-satellite service. 25.149 Section 25.149 Telecommunication FEDERAL COMMUNICATIONS COMMISSION (CONTINUED) COMMON CARRIER SERVICES SATELLITE COMMUNICATIONS Applications and Licenses...

  16. 47 CFR 25.149 - Application requirements for ancillary terrestrial components in the Mobile-Satellite Service...

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... terrestrial components in the Mobile-Satellite Service networks operating in the 1.5./1.6 GHz, 1.6/2.4 GHz and 2 GHz Mobile-Satellite Service. 25.149 Section 25.149 Telecommunication FEDERAL COMMUNICATIONS COMMISSION (CONTINUED) COMMON CARRIER SERVICES SATELLITE COMMUNICATIONS Applications and Licenses...

  17. 47 CFR 25.149 - Application requirements for ancillary terrestrial components in the mobile-satellite service...

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... terrestrial components in the mobile-satellite service networks operating in the 1.5./1.6 GHz, 1.6/2.4 GHz and 2 GHz mobile-satellite service. 25.149 Section 25.149 Telecommunication FEDERAL COMMUNICATIONS COMMISSION (CONTINUED) COMMON CARRIER SERVICES SATELLITE COMMUNICATIONS Applications and Licenses...

  18. 47 CFR 25.142 - Licensing provisions for the non-voice, non-geostationary mobile-satellite service.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ...-geostationary mobile-satellite service. 25.142 Section 25.142 Telecommunication FEDERAL COMMUNICATIONS COMMISSION (CONTINUED) COMMON CARRIER SERVICES SATELLITE COMMUNICATIONS Applications and Licenses Space Stations § 25.142 Licensing provisions for the non-voice, non-geostationary mobile-satellite service....

  19. 47 CFR 25.142 - Licensing provisions for the non-voice, non-geostationary mobile-satellite service.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ...-geostationary mobile-satellite service. 25.142 Section 25.142 Telecommunication FEDERAL COMMUNICATIONS COMMISSION (CONTINUED) COMMON CARRIER SERVICES SATELLITE COMMUNICATIONS Applications and Licenses Space Stations § 25.142 Licensing provisions for the non-voice, non-geostationary mobile-satellite service....

  20. 47 CFR 25.142 - Licensing provisions for the non-voice, non-geostationary Mobile-Satellite Service.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ...-geostationary Mobile-Satellite Service. 25.142 Section 25.142 Telecommunication FEDERAL COMMUNICATIONS COMMISSION (CONTINUED) COMMON CARRIER SERVICES SATELLITE COMMUNICATIONS Applications and Licenses Space Stations § 25.142 Licensing provisions for the non-voice, non-geostationary Mobile-Satellite Service....

  1. The Politics and Technology of Satellite Communications.

    ERIC Educational Resources Information Center

    Galloway, Jonathan F.

    The study discussed in this book approaches the task of understanding the interrelated effects of innovations on society by concentrating on one technological innovation--satellite communications--as it relates to three basic processes: the relation of innovations in communications technology to innovations in policy and the policy-making process,…

  2. An Educator's Guide to Communication Satellite Technology.

    ERIC Educational Resources Information Center

    Polcyn, Kenneth A.

    Recent developments in the area of sophisticated communications technology present challenges to the imagination of every educator. This guide provides educational planners with an awareness and understanding of communication satellite technology, its current uses, and some of the tentative plans for educational experimentation. The first part…

  3. Satellite Communications in the 1980's.

    ERIC Educational Resources Information Center

    Usunier, Pierre

    Space communications have developed tremendously since 1963 when the National Aeronautics and Space Administration (NASA) launched the synchronous communication satellite, Syncom II, into geostationary orbit. The capacity of that spacecraft was one two-circuit voice channel. Intelsat V, launched in 1980, has a capacity of 12,000 circuits plus two…

  4. Intelsat communications satellite scheduled for launch

    NASA Technical Reports Server (NTRS)

    1983-01-01

    To be placed into a highly elliptical transfer orbit by the Atlas Centaur (AC-61) launch vehicle, the INTELSAT V-F satellite has 12,000 voice circuits and 2 color television channels and incorporates a maritime communication system for ship to shore communications. The stages of the launch vehicle and the launch operations are described. A table shows the launch sequence.

  5. Cultural Effects and Uses of Communication Satellites.

    ERIC Educational Resources Information Center

    Schramm, Wilbur

    The communication satellite already has developed a mature technology. It carries a substantial part of the world's long range communication, and is now useable for special cultural and educational purposes. Major cultural effects come from its contribution to increasing enormously the flow of information in the world. It will increase human…

  6. Geostationary payload concepts for personal satellite communications

    NASA Technical Reports Server (NTRS)

    Benedicto, J.; Rinous, P.; Roberts, I.; Roederer, A.; Stojkovic, I.

    1993-01-01

    This paper reviews candidate satellite payload architectures for systems providing world-wide communication services to mobile users equipped with hand-held terminals based on large geostationary satellites. There are a number of problems related to the payload architecture, on-board routing and beamforming, and the design of the S-band Tx and L-band Rx antenna and front ends. A number of solutions are outlined, based on trade-offs with respect to the most significant performance parameters such as capacity, G/T, flexibility of routing traffic to beams and re-configuration of the spot-beam coverage, and payload mass and power. Candidate antenna and front-end configurations were studied, in particular direct radiating arrays, arrays magnified by a reflector and active focused reflectors with overlapping feed clusters for both transmit (multimax) and receive (beam synthesis). Regarding the on-board routing and beamforming sub-systems, analog techniques based on banks of SAW filters, FET or CMOS switches and cross-bar fixed and variable beamforming are compared with a hybrid analog/digital approach based on Chirp Fourier Transform (CFT) demultiplexer combined with digital beamforming or a fully digital processor implementation, also based on CFT demultiplexing.

  7. Satellite services system analysis study. Volume 3: Service equipment requirements

    NASA Technical Reports Server (NTRS)

    1981-01-01

    Service equipment mission requirements are discussed. On-orbit operations, satellite classes, and reference missions are included. Service equipment usage and requirements are considered. Equipment identification methodology is discussed. Service equipment usage is analyzed, including initial launch, revisit, Earth return, and orbital storage. A summary of service requirements and equipment is presented, including service equipment status, even interaction, satellite features, and observations.

  8. High-Latitude Communications Satellite (HILACS)

    NASA Technical Reports Server (NTRS)

    1990-01-01

    The Naval Postgraduate School in the AE 4871 Advanced Spacecraft Design course designed a communications satellite (HILACS) that will provide a continuous UHF communications link between stations located north of the region covered by geosynchronous communications satellites. The communications payload will operate only for that portion of the orbit necessary to provide specific coverage. The satellite orbit is elliptic with perigee at 1204 km in the Southern Hemisphere and an apogee at 14,930 km with 63.4 degrees inclination. Analysis and design of each of the subsystems was done to the extent possible within the constraints of an eleven week quarter and the design and analysis tools available. Work was completed in orbital analysis, the reaction control system, attitude control subsystem, electric power subsystem, telemetry, tracking, and control, thermal control subsystem, and the structures subsystem. The design team consisted of 12 students. Additional support was provided by the Jet Propulsion Laboratory and the Naval Research Laboratory.

  9. Silicon-Germanium Fast Packet Switch Developed for Communications Satellites

    NASA Technical Reports Server (NTRS)

    Quintana, Jorge A.

    1999-01-01

    Emerging multimedia applications and future satellite systems will require high-speed switching networks to accommodate high data-rate traffic among thousands of potential users. This will require advanced switching devices to enable communication between satellites. The NASA Lewis Research Center has been working closely with industry to develop a state-of-the-art fast packet switch (FPS) to fulfill this requirement. Recently, the Satellite Industry Task Force identified the need for high-capacity onboard processing switching components as one of the "grand challenges" for the satellite industry in the 21st century. In response to this challenge, future generations of onboard processing satellites will require low power and low mass components to enable transmission of services in the 100 gigabit (1011 bits) per second (Gbps) range.

  10. Satellite services for disaster management and security applications

    NASA Astrophysics Data System (ADS)

    Koudelka, Otto; Schrotter, P.

    2007-06-01

    Advantages of communications satellites are the inherent broadcast capability, high bandwidth, reliability and flexibility in network expansion. Small transportable terminals can be made operational very quickly. Recent developments in communications and computer technology allow to provide low-cost equipment, which is affordable even in developing countries. Communications satellites can also play an important role in case of emergencies or natural disasters. The combination of satellite communications and navigation can support new services for emergency teams. At the Institute of Applied Systems Technology and the Institute of Communication Networks and Satellite Communications highly transportable terminals have been developed, both for star and mesh network topologies. A fully meshed VSAT system is used for symmetrical links. For other applications, which do not require high return link capacity an asymmetrical system is an efficient solution. It uses low-cost DVB technology for the forward link and satellite phones with data capability on the return link. Novel multicast protocols allow to use these asymmetrical links in an efficient way. The paper describes the different systems and their applications in disaster management and security applications. Emphasis is put on transfer of remote sensing images and voice over IP (VoIP) as well as videoconference services.

  11. Global disaster satellite communications system for disaster assessment and relief coordination

    NASA Technical Reports Server (NTRS)

    Leroy, B. E.

    1979-01-01

    The global communication requirements for disaster assistance and examines operationally feasible satellite system concepts and the associated system parameters are analyzed. Some potential problems associated with the current method of providing disaster assistance and a scenario for disaster assistance relying on satellite communications are described. Historical statistics are used with the scenario to assess service requirements. Both present and planned commercially available systems are considered. The associated global disaster communication yearly service costs are estimated.

  12. Photogrammetric mobile satellite service prediction

    NASA Technical Reports Server (NTRS)

    Akturan, Riza; Vogel, Wolfhard J.

    1994-01-01

    Photographic images of the sky were taken with a camera through a fisheye lens with a 180 deg field-of-view. The images of rural, suburban, and urban scenes were analyzed on a computer to derive quantitative information about the elevation angles at which the sky becomes visible. Such knowledge is needed by designers of mobile and personal satellite communications systems and is desired by customers of these systems. The 90th percentile elevation angle of the skyline was found to be 10 deg, 17 deg, and 51 deg in the three environments. At 8 deg, 75 percent, 75 percent, and 35 percent of the sky was visible, respectively. The elevation autocorrelation fell to zero with a 72 deg lag in the rural and urban environment and a 40 deg lag in the suburb. Mean estimation errors are below 4 deg.

  13. Engineers checkout Early Bird-Communication Satellite

    NASA Technical Reports Server (NTRS)

    1984-01-01

    Engineers Stanley R. Peterson (left) and Ray Bowerman (right), checkout the Early Bird, the world's first communication satellite. NASA launched the satellite built by Hughes Aircraft Corporation on April 6, 1955 at 6:48pm E.S.T. from Complex 17a at Cape Kennedy, Florida. Early Bird was built for the Communications Satellite Corporation and weighed about 85 pounds after being placed in a synchronous orbit of 22,300 miles above the earth. It was positioned over the Atlantic to provide 240 two-way telephone channels or 2-way television between Europe and North America. The outer surface of Early Bird was covered with 6,000 silicon-coated solar cells, which absorbed the sun's rays to provide power to the satellite for its intricate transmitting and receiving equipment.

  14. Performance of Duplex Communication between a Leo Satellite and Terrestrial Location Using a Geo Constellation

    NASA Technical Reports Server (NTRS)

    Robinson, Daryl C.; Konangi, Vijay K.; Wallett, Thomas M.

    1998-01-01

    A network comprised of a terrestrial site, a constellation of three GEO satellites and a LEO satellite is modeled and simulated. Continuous communication between the terrestrial site and the LEO satellite is facilitated by the GEO satellites. The LEO satellite has the orbital characteristics of the International Space Station. Communication in the network is based on TCP/IP over ATM, with the ABR service category providing the QoS, at OC-3 data rate. The OSPF protocol is used for routing. We simulate FTP file transfers, with the terrestrial site serving as the client and the LEO satellite being the server. The performance characteristics are presented.

  15. Satellite Quantum Communication via the Alphasat Laser Communication Terminal

    E-print Network

    Elser, Dominique; Khan, Imran; Stiller, Birgit; Marquardt, Christoph; Leuchs, Gerd; Saucke, Karen; Tröndle, Daniel; Heine, Frank; Seel, Stefan; Greulich, Peter; Zech, Herwig; Gütlich, Björn; Richter, Ines; Meyer, Rolf

    2015-01-01

    By harnessing quantum effects, we nowadays can use encryption that is in principle proven to withstand any conceivable attack. These fascinating quantum features have been implemented in metropolitan quantum networks around the world. In order to interconnect such networks over long distances, optical satellite communication is the method of choice. Standard telecommunication components allow one to efficiently implement quantum communication by measuring field quadratures (continuous variables). This opens the possibility to adapt our Laser Communication Terminals (LCTs) to quantum key distribution (QKD). First satellite measurement campaigns are currently validating our approach.

  16. Satellite Quantum Communication via the Alphasat Laser Communication Terminal

    E-print Network

    Dominique Elser; Kevin Günthner; Imran Khan; Birgit Stiller; Christoph Marquardt; Gerd Leuchs; Karen Saucke; Daniel Tröndle; Frank Heine; Stefan Seel; Peter Greulich; Herwig Zech; Björn Gütlich; Ines Richter; Rolf Meyer

    2015-10-15

    By harnessing quantum effects, we nowadays can use encryption that is in principle proven to withstand any conceivable attack. These fascinating quantum features have been implemented in metropolitan quantum networks around the world. In order to interconnect such networks over long distances, optical satellite communication is the method of choice. Standard telecommunication components allow one to efficiently implement quantum communication by measuring field quadratures (continuous variables). This opens the possibility to adapt our Laser Communication Terminals (LCTs) to quantum key distribution (QKD). First satellite measurement campaigns are currently validating our approach.

  17. Von Karman Lecture - The rocky road to communication satellites

    NASA Astrophysics Data System (ADS)

    Wheelon, A. D.

    1986-01-01

    The history of communications satellites traced in terms of the confluence of the forces of technology, economics and public policy is discussed. The idea of placing communications satellites in GEO was put forward by a science fiction writer in 1945. Syncom II was launched, with a TWT amplifier, into GEO in 1963. Telstar provided the first live transoceanic broadcasts in 1962, just before Comsat was chartered. Early Bird proved that telephony links through GEO satellites was feasible. The follow-up, Intelsat II, was partially spurred by the Apollo program with its worldwide communications demands. Intelsat began with three spacecraft that formed the foundation for the present system. The Intelsat monopoly on worldwide common carrier links is being challenged by ground-based links and entrepreneurial activities spurred by deregulation. An open-skies policy formulated in the U.S. in the late 1960s has led to the launch of various domestic satellite systems with narrow beam transmissions using C- and Ku-band frequencies. Satellite access costs have fallen because of the capabilities of renting or selling individual transponders. Mobile communications systems may soon be served through a joint U.S.-Canada project. Finally, the WARC 1977 set the ground rules for DBS television service, which is in the process of being implemented, mainly by cable operators.

  18. Laser data links for communication satellites

    NASA Technical Reports Server (NTRS)

    Ohern, W. L.; Rodenberger, C. A.

    1974-01-01

    Laser data relays potentially offer continuous 1 Gb/sec bandwidths, drastically increasing low-altitude satellite data collection capacity over present store-and-dump techniques. Availability of the laser link as a reliable alternative, operating within conventional low-altitude communication subsystem weight and power allocations, will create customer pressure for adoption. Major communication relay system impacts are discussed including reliability, mechanical design, attitude control, on-board data handling, contamination control, and traffic-net management. Interface parameters which drive the fundamental relay satellite design concepts are discussed, and conditions requiring early quantitative analysis are identified.

  19. Laser satellite communications with adaptive optics

    NASA Astrophysics Data System (ADS)

    Ting, Chueh; Voelz, David G.; Giles, Michael K.

    2005-08-01

    Laser satellite communications (LCS) appear to have potential applications in the future global communication network. However, bidirectional ground-to-space link performance is degraded by atmospheric turbulence. This paper presents the simulations results of laser uplink and downlink propagation through atmospheric turbulence based on turbulence strength and link specification data obtained from the European Space Agency (ESA) ARTEMIS satellite and its associated optical ground station (OGS). The results obtained using this NMSU bidirectional link model indicate that the uplink performance can be improved significantly using tip-tilt error compensation alone while the downlink performance can be improved with higher order adaptive optics compensation.

  20. 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.

  1. A personal communications network using a Ka-band satellite

    NASA Technical Reports Server (NTRS)

    Palmer, Larry C.; Laborde, Enrique; Stern, Alan; Sohn, Philip Y.

    1992-01-01

    The feasibility of a personal communications network using portable terminals that can provide 4.8-kb/s voice communications to a hub station via a Ka-band geosynchronous satellite has been investigated. Tradeoffs are examined so that the combined system of hub and gateway earth stations, the satellite, and the personal terminals can provide a competitive service in terms of cost, availability, and quality. A baseline system that uses a spacecraft with approximately 140 spot beams to cover the contiguous US (CONUS) and 5-W power amplifiers in each beam is described. Satellite access in both the forward and return directions uses frequency-division multiple-access/code-division multiple-access (FDMA/CDMA) with a chip rate of 2.5 Mchip/s.

  2. 20/30 GHz satellite personal communications networks

    NASA Technical Reports Server (NTRS)

    Palmer, L. C.; Stern, A.; Sohn, P. Y.

    1992-01-01

    The feasibility of personal communications networks that can provide 4.8-kbps voice communications between portable terminals and a hub station via a Ka-band geosynchronous satellite has been investigated. Tradeoffs are examined so that the combined system of hub and gateway earth stations, the satellite, and the personal terminals can provide a competitive service in terms of cost, availability, and quality. A baseline system is described using a spacecraft with approximately 140 spot beams that cover CONUS with 5-watt power amplifiers in each beam. Satellite access in both the forward and return directions uses frequency division multiple access/code division multiple access with a chip rate of 2.5 Mchip/sec.

  3. 47 CFR 25.214 - Technical requirements for space stations in the satellite digital audio radio service and...

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... the satellite digital audio radio service and associated terrestrial repeaters. 25.214 Section 25.214 Telecommunication FEDERAL COMMUNICATIONS COMMISSION (CONTINUED) COMMON CARRIER SERVICES SATELLITE COMMUNICATIONS Technical Standards § 25.214 Technical requirements for space stations in the satellite digital audio...

  4. 47 CFR 25.214 - Technical requirements for space stations in the Satellite Digital Audio Radio Service and...

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... the Satellite Digital Audio Radio Service and associated terrestrial repeaters. 25.214 Section 25.214 Telecommunication FEDERAL COMMUNICATIONS COMMISSION (CONTINUED) COMMON CARRIER SERVICES SATELLITE COMMUNICATIONS Technical Standards § 25.214 Technical requirements for space stations in the Satellite Digital Audio...

  5. 47 CFR 25.214 - Technical requirements for space stations in the satellite digital audio radio service and...

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... the satellite digital audio radio service and associated terrestrial repeaters. 25.214 Section 25.214 Telecommunication FEDERAL COMMUNICATIONS COMMISSION (CONTINUED) COMMON CARRIER SERVICES SATELLITE COMMUNICATIONS Technical Standards § 25.214 Technical requirements for space stations in the satellite digital audio...

  6. 47 CFR 25.214 - Technical requirements for space stations in the Satellite Digital Audio Radio Service and...

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... the Satellite Digital Audio Radio Service and associated terrestrial repeaters. 25.214 Section 25.214 Telecommunication FEDERAL COMMUNICATIONS COMMISSION (CONTINUED) COMMON CARRIER SERVICES SATELLITE COMMUNICATIONS Technical Standards § 25.214 Technical requirements for space stations in the Satellite Digital Audio...

  7. 47 CFR 25.214 - Technical requirements for space stations in the satellite digital audio radio service and...

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... the satellite digital audio radio service and associated terrestrial repeaters. 25.214 Section 25.214 Telecommunication FEDERAL COMMUNICATIONS COMMISSION (CONTINUED) COMMON CARRIER SERVICES SATELLITE COMMUNICATIONS Technical Standards § 25.214 Technical requirements for space stations in the satellite digital audio...

  8. NASA Launches Next-Generation Communications Satellite

    E-print Network

    Christian, Eric

    NASA Launches Next-Generation Communications Satellite Pg 3 Triumph Over Tragedy: Columbia's Last Mission Pg 6 Goddard Day of Remembrance Pg 9 National Aeronautics and Space Administration www.nasa.gov Volume 9 Issue 1 February 2013 #12;T he first of NASA's three next-generation Tracking and Data Relay

  9. Characteristics of a future aeronautical satellite communications system

    NASA Technical Reports Server (NTRS)

    Sohn, Philip Y.; Stern, Alan; Schmidt, Fred

    1991-01-01

    A possible operational system scenario for providing satellite communications services to the future aviation community was analyzed. The system concept relies on a Ka-band (20/30 GHz) satellite that utilizes Multibeam Antenna (MBA) technology. The aircraft terminal uses an extremely small aperture antenna as a result of using this higher spectrum at Ka-band. The satellite functions as a relay between the aircraft and the ground stations. The ground stations function as interfaces to the existing terrestrial networks such as the Public Service Telephone Network (PSTN). Various system tradeoffs are first examined to ensure optimized system parameters. High level performance specifications and design approaches are generated for the space, ground, and aeronautical elements in the system. Both technical and economical issues affecting the feasibility of the studied concept are addressed with the 1995 timeframe in mind.

  10. Characteristics of a future aeronautical satellite communications system

    NASA Technical Reports Server (NTRS)

    Sohn, Philip Y.; Stern, Alan; Schmidt, Fred

    1991-01-01

    A possible operational system scenario for providing satellite communications services to the future aviation community was analyzed. The system concept relies on a Ka-band (20/30 GHz) satellite that utilizes multibeam antenna (MBA) technology. The aircraft terminal uses an extremely small aperture antenna as a result of using this higher spectrum at Ka-band. The satellite functions as a relay between the aircraft and the ground stations. The ground stations function as interfaces to the existing terrestrial networks such as the Public Service Telephone Network (PSTN). Various system tradeoffs are first examined to ensure optimized system parameters. High level performance specifications and design approaches are generated for the space, ground, and aeronautical elements in the system. Both technical and economical issues affecting the feasibility of the studied concept are addressed with the 1995 timeframe in mind.

  11. Mobile satellite communications - Vehicle antenna technology update

    NASA Technical Reports Server (NTRS)

    Bell, D.; Naderi, F. M.

    1986-01-01

    This paper discusses options for vehicle antennas to be used in mobile satellite communications systems. Two types of antennas are identified. A non-steerable, azimuthally omnidirectional antenna with a modest gain of 3 to 5 dBi is suggested when a low cost is desired. Alternatively, mechanically or electronically steerable antennas with a higher gain of 10 to 12 dBi are suggested to alleviate power and spectrum scarcity associated with mobile satellite communications. For steerable antennas, both open-loop and closed-loop pointing schemes are discussed. Monopulse and sequential lobing are proposed for the mechanically steered and electronically steered antennas, respectively. This paper suggests a hybrid open-loop/closed-loop pointing technique as the best performer in the mobile satellite environment.

  12. Designing Satellite Communication Networks by Zero-One Quadratic Programming

    E-print Network

    Helme, Marcia P.

    In satellite communications networks, distinctive facilities called homing stations perform special transmission functions. Local demand nodes clustered around each homing station communicate with each other via a local ...

  13. Satellite mobile data service for Canada

    NASA Technical Reports Server (NTRS)

    Egan, Glenn R.; Sward, David J.

    1990-01-01

    A commercial mobile satellite system which is to be constructed and operated in Canada is examined. This is done in two phases. First, mobile data services was introduced. Hub equipment and 3000 mobile data terminals were supplied. Over the satellite tests were performed. The mobile data service provides full two way digital messaging automatic vehicle location and fleet management services. The second phase is to construct, launch and make operational the MSAT satellite and associated network control facilities. The implementation is examined of the mobile data service in Canada, including the technical description. Marketing and applications are also examined.

  14. Innovative Networking Concepts Tested on the Advanced Communications Technology Satellite

    NASA Technical Reports Server (NTRS)

    Friedman, Daniel; Gupta, Sonjai; Zhang, Chuanguo; Ephremides, Anthony

    1996-01-01

    This paper describes a program of experiments conducted over the advanced communications technology satellite (ACTS) and the associated TI-VSAT (very small aperture terminal). The experiments were motivated by the commercial potential of low-cost receive only satellite terminals that can operate in a hybrid network environment, and by the desire to demonstrate frame relay technology over satellite networks. The first experiment tested highly adaptive methods of satellite bandwidth allocation in an integrated voice-data service environment. The second involved comparison of forward error correction (FEC) and automatic repeat request (ARQ) methods of error control for satellite communication with emphasis on the advantage that a hybrid architecture provides, especially in the case of multicasts. Finally, the third experiment demonstrated hybrid access to databases and compared the performance of internetworking protocols for interconnecting local area networks (LANs) via satellite. A custom unit termed frame relay access switch (FRACS) was developed by COMSAT Laboratories for these experiments; the preparation and conduct of these experiments involved a total of 20 people from the University of Maryland, the University of Colorado and COMSAT Laboratories, from late 1992 until 1995.

  15. Plan of advanced satellite communication experiments using ETS-6

    NASA Technical Reports Server (NTRS)

    Ikegami, Tetsushi

    1989-01-01

    In 1992, an Engineering Test Satellite 6 is scheduled to be launched by an H-2 rocket. The missions of ETS-6 are to establish basic technologies of inter-satellite communications using S-band, millimeter waves and optical beams and of fixed and mobile satellite communications using multibeam antenna on board the satellite. A plan of the experiments is introduced.

  16. Need for, and financial feasibility of, satellite-aided land mobile communications

    NASA Technical Reports Server (NTRS)

    Castruccio, P. A.; Marantz, C. S.; Freibaum, J.

    1982-01-01

    Questions regarding the role of a mobile-satellite system in augmenting the terrestrial communications system are considered, and a market assessment study is discussed. Aspects of an investment analysis are examined, taking into account a three phase financial study of four postulated land Mobile Satellite Service (LMSS) systems, project profitability evaluation methods, risk analysis methods, financial projections, potential investor acceptance standards, and a risk analysis. It is concluded that a satellite augmented terrestrial mobile service appears to be economically and technically superior to a service depending exclusively on terrestrial systems. The interest in the Mobile Satellite Service is found to be worldwide, and the ground equipment market is potentially large.

  17. A generalized transmultiplexer and its application to mobile satellite communications

    NASA Technical Reports Server (NTRS)

    Ichiyoshi, Osamu

    1990-01-01

    A generalization of digital transmultiplexer technology is presented. The proposed method can realize transmultiplexer (TMUX) and transdemultiplexer (TDUX) filter banks whose element filters have bandwidths greater than the channel spacing frequency. This feature is useful in many communications applications. As an example, a satellite switched (SS) Frequency Division Multiple Access (FDMA) system is proposed for spot beam satellite communications, particularly for mobile satellite communications.

  18. AIAA 2004-3150 ARCHITECTING A COMMUNICATION SATELLITE PRODUCT LINE

    E-print Network

    de Weck, Olivier L.

    AIAA 2004-3150 ARCHITECTING A COMMUNICATION SATELLITE PRODUCT LINE Rania Hassan* Olivier de Weck of commercial communication satellites. NOMENCLATURE SAA solar array area radiatorA thermal radiator area c Communications Satellite Systems Conference & Exhibit 2004 9 - 12 May 2004, Monterey, California AIAA 2004

  19. WDM Polymer Substrate Mode Photonic Interconnects for Satellite Communications

    E-print Network

    Chen, Ray

    WDM Polymer Substrate Mode Photonic Interconnects for Satellite Communications Jian Liu Polar is an enabling technology for future satellite communications to increase capacity ofbandwidth and network-3]. Compared with RF satellite communications, they use much smaller antenna aperture size and consume less

  20. Causal relationships between solar proton events and single event upsets for communication satellites

    E-print Network

    Lohmeyer, Whitney Quinne

    In this work, we analyze a historical archive of single event upsets (SEUs) maintained by Inmarsat, one of the world's leading providers of global mobile satellite communications services. Inmarsat has operated its ...

  1. Method for scrambling satellite communications

    NASA Technical Reports Server (NTRS)

    Brockman, Milton H. (Inventor)

    1992-01-01

    A secure communications system multiplexes segments of the information signal for keyed encoding and modulation onto a plurality of different carrier frequencies and/or polarizations, and transmits the encoded carriers to multi-channel signal summing receivers that decode the segments from all channels, to reassemble the information signal for use by authorized stations with a key. The use of the multi-channel link and the summing receiver allows the greatest number of different coding algorithms for accommodating the greatest number of discrete secure channels.

  2. Echo compensation for the German communications satellite

    NASA Astrophysics Data System (ADS)

    Wehrmann, R.

    Research with the aim of realizing echo compensators for time-variable systems for the German communications satellite is reported. The principle of satellite connection with echo compensators is discussed and the mode of operation of known compensators for time-invariant systems is described. The time-variable system structure of echo series in two-wire telecommunications systems is addressed along with the structure of an echo compensator for identifying and reproducing such systems. Finally, first simulation results for identifying purely time-variable echo series transmission functions are reported.

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

    NASA Technical Reports Server (NTRS)

    1977-01-01

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

  4. Satellite switched FDMA advanced communication technology satellite program

    NASA Technical Reports Server (NTRS)

    Atwood, S.; Higton, G. H.; Wood, K.; Kline, A.; Furiga, A.; Rausch, M.; Jan, Y.

    1982-01-01

    The satellite switched frequency division multiple access system provided a detailed system architecture that supports a point to point communication system for long haul voice, video and data traffic between small Earth terminals at Ka band frequencies at 30/20 GHz. A detailed system design is presented for the space segment, small terminal/trunking segment at network control segment for domestic traffic model A or B, each totaling 3.8 Gb/s of small terminal traffic and 6.2 Gb/s trunk traffic. The small terminal traffic (3.8 Gb/s) is emphasized, for the satellite router portion of the system design, which is a composite of thousands of Earth stations with digital traffic ranging from a single 32 Kb/s CVSD voice channel to thousands of channels containing voice, video and data with a data rate as high as 33 Mb/s. The system design concept presented, effectively optimizes a unique frequency and channelization plan for both traffic models A and B with minimum reorganization of the satellite payload transponder subsystem hardware design. The unique zoning concept allows multiple beam antennas while maximizing multiple carrier frequency reuse. Detailed hardware design estimates for an FDMA router (part of the satellite transponder subsystem) indicate a weight and dc power budget of 353 lbs, 195 watts for traffic model A and 498 lbs, 244 watts for traffic model B.

  5. Traffic model for advanced satellite designs and experiments for ISDN services

    NASA Technical Reports Server (NTRS)

    Pepin, Gerard R.; Hager, E. Paul

    1991-01-01

    The data base structure and fields for categorizing and storing Integrated Services Digital Network (ISDN) user characteristics is outlined. This traffic model data base will be used to exercise models of the ISDN Advanced Communication Satellite to determine design parameters and performance for the NASA Satellite Communications Applications Research (SCAR) Program.

  6. CTS United States experiments - A progress report. [Communications Technology Satellite for high power broadcasting

    NASA Technical Reports Server (NTRS)

    Robbins, W. H.; Donoughe, P. L.

    1976-01-01

    The Communications Technology Satellite (CTS) is a high-power broadcast satellite launched by NASA on January 17, 1976. CTS is the first satellite to operate at a frequency of 12 gigahertz and incorporates technology making possible new satellite telecommunications services. CTS is a cooperative program of the United States and Canada. This paper presents the results of the United States experimental activity to date. Wide segments of the population are involved in the Experiments Program, including the scientific community, other government agencies, industry, and the education and health entities. The experiments are associated with both technological objectives and the demonstration of new community and social services via satellite.

  7. United States societal experiments via the Communications Technology Satellite

    NASA Technical Reports Server (NTRS)

    Donoughe, P. L.

    1976-01-01

    After a brief description of the Communication Technology Satellite and its U.S. coverage, the U.S. societal experiments via the CTS are discussed. These include education (college curriculum sharing, and project interchange), health care (biomedical communications, health communications, and communication support for decentralized education), and community and special experiments (satellite library information network, and transportable earth terminal).

  8. World-wide aeronautical satellite communications

    NASA Technical Reports Server (NTRS)

    Wood, Peter; Smith, Keith

    1988-01-01

    INMARSAT decided to expand the spectrum covered by its new generation of satellites, INMARSAT-2, to include 1 MHz (subsequently increased to 3 MHz) of the spectrum designed for aeronautical use. It began a design study that led to the specifications for the system that is now being implemented. Subsequently, INMARSAT awarded contracts for the design of avionics and high gain antennas to a number of manufactures, while several of the signatories that provide ground equipment for communicating with the INMARSAT satellites are modifying their earth stations to work with the avionic equipment. As a resullt of these activities, a world-wide aeronautical satellite system supporting both voice and data will become operational in 1989.

  9. An experiment to enable commercial mobile satellite service

    NASA Technical Reports Server (NTRS)

    Lovell, R. R.; Knouse, G. H.; Weber, W. J.

    1982-01-01

    A Mobile Satellite Experiment (MSAT-X) is described, based on a planned cooperative U.S./Canadian program. The experiment would establish network architecture, develop system and ground-segment technology, and define the technical characteristics needed to help structure the regulatory/institutional framework needed to enable a first-generation commercial satellite service. A satellite of this type would augment terrestrial systems, both cellular and noncellular, in the thin-route/rural areas of the country where service is either unavailable or inadequate. Applications range from wide-area radio/dispatch (e.g., oil exploration and interstate trucking) to extension of the public mobile telephone service. Market estimates are provided and experiment objectives and requirements are delineated. The requirements are being developed in close coordination with the Department of Communications (DOC) of Canada and with industry and potential-user organizations. The paper closes with a development plan and milestone chart.

  10. 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.

  11. Propulsion requirements for communications satellites.

    NASA Technical Reports Server (NTRS)

    Isley, W. C.; Duck, K. I.

    1972-01-01

    The concept of characteristics thrust is introduced herein as a means of classifying propulsion system tasks related particularly to geosynchronous communications spacecraft. Approximate analytical models are developed to permit estimation of characteristic thrust for injection error corrections, orbit angle re-location, north-south station keeping, east-west station keeping, spin axis precession control, attitude rate damping, and orbit raising applications. Performance assessment factors are then outlined in terms of characteristic power, characteristic weight, and characteristic volume envelope, which are related to the characteristic thrust. Finally, selected performance curves are shown for power as a function of spacecraft weight, including the influence of duty cycle on north-south station keeping, a 90 degree orbit angle re-location in 14 days, and finally comparison of orbit raising tasks from low and intermediate orbits to a final geosynchronous station. Power requirements range from less than 75 watts for north-south station keeping on small payloads up to greater than 15 KW for a 180 day orbit raising mission including a 28.5 degree plane change.

  12. Voice intelligibility in satellite mobile communications

    NASA Technical Reports Server (NTRS)

    Wishna, S.

    1973-01-01

    An amplitude control technique is reported that equalizes low level phonemes in a satellite narrow band FM voice communication system over channels having low carrier to noise ratios. This method presents at the transmitter equal amplitude phonemes so that the low level phonemes, when they are transmitted over the noisey channel, are above the noise and contribute to output intelligibility. The amplitude control technique provides also for squelching of noise when speech is not being transmitted.

  13. Intersatellite link application to commercial communications satellites

    NASA Technical Reports Server (NTRS)

    Lee, Young S.; Atia, Ali E.; Ponchak, Denise S.

    1988-01-01

    The fundamental characteristics of intersatellite link (ISL) systems, and their application to domestic, regional, and global satellite communications, are described. The quantitative advantages of using ISLs to improve orbit utilization, spectrum occupancy, transmission delay (compared to multi-hop links), coverage, and connectivity, and to reduce the number of earth station antennas, are also presented. Cost-effectiveness and other systems benefits of using ISLs are identified, and the technical and systems planning aspects of ISL systems implementation are addressed.

  14. Channel simulation to facilitate mobile-satellite communications research

    NASA Technical Reports Server (NTRS)

    Davarian, Faramaz

    1987-01-01

    The mobile-satellite-service channel simulator, which is a facility for an end-to-end hardware simulation of mobile satellite communications links is discussed. Propagation effects, Doppler, interference, band limiting, satellite nonlinearity, and thermal noise have been incorporated into the simulator. The propagation environment in which the simulator needs to operate and the architecture of the simulator are described. The simulator is composed of: a mobile/fixed transmitter, interference transmitters, a propagation path simulator, a spacecraft, and a fixed/mobile receiver. Data from application experiments conducted with the channel simulator are presented; the noise converison technique to evaluate interference effects, the error floor phenomenon of digital multipath fading links, and the fade margin associated with a noncoherent receiver are examined. Diagrams of the simulator are provided.

  15. LOOPUS Mobile D - A new mobile communication satellite system

    NASA Astrophysics Data System (ADS)

    Nauck, J.; Horn, P.; Goeschel, W.

    The design concept of a European land-mobile communication (LMC) system using satellites in inclined orbits is outlined. The space segment is based on the LOOPUS (loops in orbits occupied permanently by unstationary satellites) concept; nine such satellites could provide continuous redundant availability at the high elevation angles (60-90 deg) needed to eliminate LMC shadowing problems in urban areas. The orbit configuration would provide coverage of zones in North America and East Asia as well. Details of the system architecture, services, and space and user hardware for LOOPUS Mobile D are discussed and illustrated with extensive diagrams and maps; also considered is the relationship of a LOOPUS-based system to a ground-based European LMC network.

  16. Feasibility of NASA TT&C via Commercial Satellite Services

    NASA Technical Reports Server (NTRS)

    Mitchell, Carl W.; Weiss, Roland

    1997-01-01

    This report presents the results of a study to identify impact and driving requirements by implementing commercial satellite communications service into traditional National Aeronautics and Space Administration (NASA) space-ground communications. The NASA communication system is used to relay spacecraft and instrument commands, telemetry and science data. NASA's goal is to lower the cost of operation and increase the flexibility of spacecraft operations. Use of a commercial network offers the opportunity to contact a spacecraft on a nearly "on-demand" basis with ordinary phone calls to enable real time interaction with science events.

  17. 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).

  18. Concept for advanced satellite communications and required technologies

    NASA Technical Reports Server (NTRS)

    Ramler, J. R.; Salzman, J. A.

    1982-01-01

    The advanced communications technology satellite (ACTS) program of NASA is aimed at the development of high risk technologies that will enable exploiting higher frequency bands and techniques for improving frequency reuse. The technologies under development include multiple beam spacecraft antennas, on-board switching and processing, RF devices and components and advanced earth stations. The program focus is on the Ka-band (30/20 GHz) as the implementing frequency since it has five times the bandwidth of either the C- or Ku-bands. However, the technology being developed is applicable to other frequency bands as well and will support a wide range of future communications systems required by NASA, other Government agencies and the commercial sector. An overview is presented of an operational 30/20 GHz satellite system that may evolve. How the system addresses service requirements is discussed, and the technology required and being developed is considered. Previously announced in STAR as N83-11210

  19. Concept for advanced satellite communications and required technologies

    NASA Technical Reports Server (NTRS)

    Ramler, J. R.; Salzman, J. A.

    1982-01-01

    The advanced communications technology satellite (ACTS) program of NASA is aimed at the development of high risk technologies that will enable exploiting higher frequency bands and techniques for improving frequency reuse. The technologies under development include multiple beam spacecraft antennas, on-board switching and processing, RF devices and components and advanced Earth stations. The program focus is on the Ka-band (30/20 GHz) as the implementing frequency since it has five times the bandwidth of either the C- or Ku-bands. However, the technology being developed is applicable to other frequency bands as well and will support a wide range of future communications systems required by NASA, other Government agencies and the commercial sector. An overview is presented of an operational 30/20 GHz satellite system that may evolve. How the system addresses service requirements is discussed, and the technology required and being developed is considered.

  20. Leveraging Commercial Communication Satellites to support the Space Situational

    NASA Astrophysics Data System (ADS)

    Deaver, T.

    The majority of USSTRATCOM detect and track requirements in the geosynchronous regime could be met via strategic placement of medium grade optical sensors on select geosynchronous satellites at relatively low cost in less than 48 months. An architecture which includes hosting SSA sensors on eight to ten commercial communication satellites could provide for highly accurate, timely and relatively inexpensive detect and track capabilities. The major factors considered when hosting any sensor on a commercial communications satellite are size, weight (mass) and power or SWAP. Additional sensor specific items must also be considered to form a complete feasibility analysis. These include data rate, mounting constraints, thermal balance, timing accuracy, and attitude stability requirements. All of these factors directly impact the cost and flexibility of hosting such a sensor on a geosynchronous communication satellite. By choosing a relatively light weight, low power consumption sensor which requires a small amount of bandwidth to transmit its data, the cost of hosting the sensor is kept to a minimum. Once the type of sensor or sensors is identified, the next step is to identify idea geosynchronous locations for the "hosted" sensors. Once these locations are identified, then one would identify a potential host which needs to be replaced within the desired timeframe. Once the host is identified, then the satellite owner / operator should be approached about hosting a "neighborhood" watch sensor aboard their spacecraft. Commercial satellites are routinely replaced based on age, lack of available station keeping fuel or to allow a service provider to upgrade its capabilities. Each commercial communication satellite operator maintains a plan of replacing spacecraft. Between the two largest commercial SATCOM providers, INTELSAT and SES, six to eight spacecraft will be replaced each year (100 plus spacecraft with 15 year average lifetimes). The satellites are usually procured, designed, built, launched and operational within 36 months. In order for the US Government to adapt to this timeline, a sensor specification would need to be established as well as a sensor procurement pipeline. The sensors would then be provided to the satellite bus manufacturer for integration onto the bus. The spacecraft would then be launched and operated by the commercial SATCOM operator for the life of the spacecraft. Based on this approach, it is highly conceivable that a complete geosynchronous "neighborhood" watch program could be completed within 48 months of initiation.

  1. Data communications service by VSAT network in the Philippines

    NASA Astrophysics Data System (ADS)

    Duque, Roberto L.

    Satellite communications is of particular importance to an archipelago like the Philippines. With over 7,100 islands, rugged forests, and mountainous terrain, satellite communications technology offers the opportunity to leapfrog over the existing difficulties associated with terrestrial-based microwave networks. If harnessed correctly, it has the potential to significantly contribute to the provisions of a wide array of services ranging from voice to facsimile and data to video. The continuous evolution of satellite and earth station technology, since its inception more than 30 years ago, has placed within reach technologies which are reliable as well as easily deployed, used, and maintained. The Philippine government's recognition of the vital role of wireless communications was never more evident than during and after the series of natural calamities that hit the country and disrupted existing microwave infrastructure. Aside from obvious technological advantages over conventional communications technologies, satellite communications provides cost-effective solutions and fortifies the country's unstable communications infrastructure.

  2. Engineering calculations for communications satellite systems planning

    NASA Technical Reports Server (NTRS)

    Martin, C. H.; Gonsalvez, D. J.; Levis, C. A.; Wang, C. W.

    1983-01-01

    Progress is reported on a computer code to improve the efficiency of spectrum and orbit utilization for the Broadcasting Satellite Service in the 12 GHz band for Region 2. It implements a constrained gradient search procedure using an exponential objective function based on aggregate signal to noise ratio and an extended line search in the gradient direction. The procedure is tested against a manually generated initial scenario and appears to work satisfactorily. In this test it was assumed that alternate channels use orthogonal polarizations at any one satellite location.

  3. An Earth Orbiting Satellite Service and Repair Facility

    NASA Technical Reports Server (NTRS)

    Berndt, Andrew; Cardoza, Mike; Chen, John; Daley, Gunter; Frizzell, Andy; Linton, Richard; Rast, Wayne

    1989-01-01

    A conceptual design was produced for the Geosynchronous Satellite Servicing Platform (GSSP), an orbital facility capable of repairing and servicing satellites in geosynchronous orbit. The GSSP is a man-tended platform, which consists of a habitation module, operations module, service bay and truss assembly. This design review includes an analysis of life support systems, thermal and power requirements, robotic and automated systems, control methods and navigation, and communications systems. The GSSP will utilize existing technology available at the time of construction, focusing mainly on modifying and integrating existing systems. The entire facility, along with two satellite retrieval vehicles (SRV), will be placed in geosynchronous orbit by the Advanced Launch System. The SRV will be used to ferry satellites to and from the GSSP. Technicians will be transferred from Earth to the GSSP and back in an Apollo-derived Crew Transfer Capsule (CTC). These missions will use advanced telerobotic equipment to inspect and service satellites. Four of these missions are tentatively scheduled per year. At this rate, the GSSP will service over 650 satelites during the projected 25 year lifespan.

  4. Flow Control and Active Queue Management for Integrated Services in an Aeronautical Satellite Network

    E-print Network

    Baras, John S.

    Flow Control and Active Queue Management for Integrated Services in an Aeronautical Satellite}@umd.edu The IP-based broadband aeronautical satellite network will provide numerous new applications and services realizable. However the performance of data communication protocols and applications over aeronautical

  5. Discussion on the progress and future of satellite communication (Japan)

    NASA Technical Reports Server (NTRS)

    Ogata, M.; Mizusawa, H.; Irie, K.

    1985-01-01

    The current status of communications satellite development in Japan is presented. It is shown that beginning with research on satellite communucations in the late 1950's, progress was made in the areas of communications, remote sensing, and technology experimentation. The current status of communication satellites is presented, stressing development in the areas of CFRP construction elements, the use of LSI and MIC circuits, advanced multibeam antenna systems, Ku and Ka band transmission systems, and the shift to small-scale earth stations. Methods for reducing costs and increasing transmission efficiency are shown. The technical specifications of all satellite projects currently under development are given. Users of Japanese communications satellite are presented.

  6. Polarization Tracking Study of Earth Station in Satellite Communications

    NASA Astrophysics Data System (ADS)

    Ma, Lihua; Hu, Chao; Pei, Jun

    2016-01-01

    Satellite communications, in telecommunications, the use of satellite can provide communications links between various points on the earth. Typical satellite communication is composed of a communication satellite, a signal transmitter and a signal receiver. As the signal transmitter or the signal receiver, an earth station plays a vital role in the satellite communications. Accurately adjustment of antenna azimuth, elevation and polarization angles on the earth station is the key to satellite communications. In the present paper, a study of polarization tracking of earth station is presented, and a detailed adjustment procession of the polarization angle is given. Combing with observation series of MEASAT-2 satellite in geostationary orbit, the polarization tracking accuracy is verified. The method can be embeded into computer program of antenna polarization adjustment in earth station.

  7. NOAA Satellite and Information Service The National Environmental Satellite, Data, and Information Service (NESDIS) is dedicated to providing

    E-print Network

    NOAA Satellite and Information Service Mission The National Environmental Satellite, Data satellites and other sources to promote, protect, and enhance the Nation's economy, security, environment the Nation's operational environmental satellites, · operates the NOAA National Data Centers, · provides data

  8. Adaptive Multimedia Communication over Satellite Routed IP Michael Welzl

    E-print Network

    Welzl, Michael

    Adaptive Multimedia Communication over Satellite Routed IP Michael Welzl Telecooperation Department encountered are the same, it seems as though adaptive multimedia communication over satellite has been was chartered in 1997, numerous issues with TCP over satellite have been addressed. Although the difficulties

  9. KA-BROADBAND SATELLITE COMMUNICATION USING CYCLOSTATIONARY PARABOLIC BEAMFORMING

    E-print Network

    Blostein, Steven D.

    KA-BROADBAND SATELLITE COMMUNICATION USING CYCLOSTATIONARY PARABOLIC BEAMFORMING by PAUL LUSINA for Military Satellite Communications : : : : : : : : 7 2.1.2 Performance of Contour Shaped Beam Antennas of a broadband satellite system which operates at the Ka frequency band. A channel model was developed which

  10. A New Era Begins: Satellite Communications and Development.

    ERIC Educational Resources Information Center

    Pelton, Joseph N.

    This overview of changes in the field of telecommunications development produced by satellite communications over the last 15 years focuses on applications of satellite systems for educational and health purposes in developing countries. Satellite communications development from 1974 to 1986 is identified as the first stage of telecommunications…

  11. The 30/20 GHz fixed communications systems service demand assessment. Volume 3: Appendices

    NASA Technical Reports Server (NTRS)

    Gabriszeski, T.; Reiner, P.; Rogers, J.; Terbo, W.

    1979-01-01

    The market analysis of voice, video, and data 18/30 GHz communications systems services and satellite transmission services is discussed. Detail calculations, computer displays of traffic, survey questionnaires, and detailed service forecasts are presented.

  12. Mobile radio group communications by satellite

    NASA Astrophysics Data System (ADS)

    Leung, Victor C. M.

    1993-05-01

    Mobile radio group communications enable a closed group of users to communicate among themselves using push-to-talk (PTT), half duplex transmissions, such that one's transmission is received by all. This paper presents new protocol designs which support group communications over mobile satellite systems. A new demand assignment multiple access (DAMA) protocol is necessitated by the inappropriateness of call-based channel assignments. Channels are assigned to individual user-groups engaged in active conversations. As members of a user-group contend for access to the assigned channel, access control by the usual manual methods is ineffective due to the very long round trip delay. A novel signaling protocol which automates access control is proposed. Carrier sensing, signal capture, and collision detection are employed to minimize access contentions. The throughput and holding time of the assigned channel are analyzed. Numerical results show that the access control protocol improves the capacity of the assigned channel by up to 65 percent.

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

    NASA Technical Reports Server (NTRS)

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

    1999-01-01

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

  14. HR SERVICES COMMUNICATION SESSION

    E-print Network

    ­ Staff Management Report revamp ­ Staff Profile ­ Externally Funded Cost Centres · HR Services Service · Science · Office of the Registrar · Buildings and Services Aisling Croke Account Lead 1 · Agriculture

  15. Comparison of INMARSAT and ATS3 satellite communication

    SciTech Connect

    Not Available

    1993-03-29

    There exists a need to provide communication through a satellite- based network which allows a user to communicate from a remote site to a fixed site. This discussion provides a comparison, both technical and financial, between the existing ATS3 satellite system and the commercial INMARSAT system. This comparison identified the limitations of each system to provide various types of communication.

  16. Presentations of the Ninth Advanced Communications Technology Satellite Propagation Studies Workshop (APSW IX)

    NASA Technical Reports Server (NTRS)

    Golshan, Nasser (Editor)

    1997-01-01

    The Advanced Communications Technology Satellite Propagation Studies Workshop (APSW) is convened each year to present the results of the ACTS Propagation Campaign. Representatives from the satellite communications (satcom) industry, academia, and government are invited to APSW for discussions and exchange of information. The ACTS Propagation campaign is completing three years of Ka-Band data collection at seven sites in North America. Through this effort, NASA is making a major contribution to growth of satcom services by providing timely propagation data and models for predicting the performance of Ka-Band satellite communications systems.

  17. A digitally implemented communications experiment utilizing the communications technology satellite, Hermes

    NASA Technical Reports Server (NTRS)

    Jackson, H. D.; Fiala, J.

    1980-01-01

    Developments which will reduce the costs associated with the distribution of satellite services are considered with emphasis on digital communication link implementation. A digitally implemented communications experiment (DICE) which demonstrates the flexibility and efficiency of digital transmission of television video and audio, telephone voice, and high-bit-rate data is described. The utilization of the DICE system in a full duplex teleconferencing mode is addressed. Demonstration teleconferencing results obtained during the conduct of two sessions of the 7th AIAA Communication Satellite Systems Conference are discussed. Finally, the results of link characterization tests conducted to determine (1) relationships between the Hermes channel 1 EIRP and DICE model performance and (2) channel spacing criteria for acceptable multichannel operation, are presented.

  18. Propagation considerations in satellite communication systems

    NASA Astrophysics Data System (ADS)

    Brussaard, Gert; Rogers, David V.

    1990-07-01

    Radio wave propagation phenomena that affect the performance of satellite communication systems are concisely discussed to introduce some topics in propagation research related to satellite systems design and to illustrate related problems and uncertainties. The focus is on troposphere effects. A summary of relevant propagation impairments is supplied, and general classes of impairments, the physical cause of each, and the major importance of each for sattelite systems are given Some impairments in the table are critically important of each for certain systems applications. For example, attenuation due to rainfall can be substantial for significant percentages of the time on 30/20-GHz propagation paths and will be the dominant path impairment for most Ka-band systems. Appropriate literature sources are referenced for the additional details that will be required for many applications.

  19. The communication-satellite market to the year 2000

    NASA Astrophysics Data System (ADS)

    van Duinen, R. J.

    1984-10-01

    The developmental history of communication satellites (CSs) is traced; the demands placed on industry by the increasing sophistication of CS payloads, the need to adapt the CS to different launchers (STS or Ariane), and the requirement of longer service life are reviewed; and the evolution of the markets for fixed (telephone, telex, and facsimile), video, business, and broadcasting service is projected over the period 1980-2000 and illustrated with tables and graphs. It is predicted that the worldwide market, expressed in terms of the demand for 36-Mhz transponders, will increase from 426 in 1980 to 1410 in 1985, 3100 in 1990, 5580 in 1995, and 9870 in 2000, with the main increase in transponders for voice communications. The potential for Netherlands participation in the growth of the CS market is evaluated, and the need for government leadership and for active promotion efforts is stressed.

  20. ESA personal communications and digital audio broadcasting systems based on non-geostationary satellites

    NASA Technical Reports Server (NTRS)

    Logalbo, P.; Benedicto, J.; Viola, R.

    1993-01-01

    Personal Communications and Digital Audio Broadcasting are two new services that the European Space Agency (ESA) is investigating for future European and Global Mobile Satellite systems. ESA is active in promoting these services in their various mission options including non-geostationary and geostationary satellite systems. A Medium Altitude Global Satellite System (MAGSS) for global personal communications at L and S-band, and a Multiregional Highly inclined Elliptical Orbit (M-HEO) system for multiregional digital audio broadcasting at L-band are described. Both systems are being investigated by ESA in the context of future programs, such as Archimedes, which are intended to demonstrate the new services and to develop the technology for future non-geostationary mobile communication and broadcasting satellites.

  1. 47 CFR 25.145 - Licensing provisions for the Fixed-Satellite Service in the 20/30 GHz bands.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 47 Telecommunication 2 2013-10-01 2013-10-01 false Licensing provisions for the Fixed-Satellite... (CONTINUED) COMMON CARRIER SERVICES SATELLITE COMMUNICATIONS Applications and Licenses Space Stations § 25.145 Licensing provisions for the Fixed-Satellite Service in the 20/30 GHz bands. (a) Except...

  2. 47 CFR 25.144 - Licensing provisions for the 2.3 GHz satellite digital audio radio service.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 47 Telecommunication 2 2014-10-01 2014-10-01 false Licensing provisions for the 2.3 GHz satellite... (CONTINUED) COMMON CARRIER SERVICES SATELLITE COMMUNICATIONS Applications and Licenses Space Stations § 25.144 Licensing provisions for the 2.3 GHz satellite digital audio radio service. (a)...

  3. 47 CFR 25.145 - Licensing conditions for the Fixed-Satellite Service in the 20/30 GHz bands.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 47 Telecommunication 2 2011-10-01 2011-10-01 false Licensing conditions for the Fixed-Satellite... (CONTINUED) COMMON CARRIER SERVICES SATELLITE COMMUNICATIONS Applications and Licenses Space Stations § 25.145 Licensing conditions for the Fixed-Satellite Service in the 20/30 GHz bands. (a) Except...

  4. 47 CFR 25.144 - Licensing provisions for the 2.3 GHz satellite digital audio radio service.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 47 Telecommunication 2 2011-10-01 2011-10-01 false Licensing provisions for the 2.3 GHz satellite... (CONTINUED) COMMON CARRIER SERVICES SATELLITE COMMUNICATIONS Applications and Licenses Space Stations § 25.144 Licensing provisions for the 2.3 GHz satellite digital audio radio service. (a)...

  5. 47 CFR 25.145 - Licensing conditions for the Fixed-Satellite Service in the 20/30 GHz bands.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 47 Telecommunication 2 2012-10-01 2012-10-01 false Licensing conditions for the Fixed-Satellite... (CONTINUED) COMMON CARRIER SERVICES SATELLITE COMMUNICATIONS Applications and Licenses Space Stations § 25.145 Licensing conditions for the Fixed-Satellite Service in the 20/30 GHz bands. (a) Except...

  6. 47 CFR 25.144 - Licensing provisions for the 2.3 GHz satellite digital audio radio service.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 47 Telecommunication 2 2013-10-01 2013-10-01 false Licensing provisions for the 2.3 GHz satellite... (CONTINUED) COMMON CARRIER SERVICES SATELLITE COMMUNICATIONS Applications and Licenses Space Stations § 25.144 Licensing provisions for the 2.3 GHz satellite digital audio radio service. (a)...

  7. 47 CFR 25.144 - Licensing provisions for the 2.3 GHz satellite digital audio radio service.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 47 Telecommunication 2 2012-10-01 2012-10-01 false Licensing provisions for the 2.3 GHz satellite... (CONTINUED) COMMON CARRIER SERVICES SATELLITE COMMUNICATIONS Applications and Licenses Space Stations § 25.144 Licensing provisions for the 2.3 GHz satellite digital audio radio service. (a)...

  8. 47 CFR 25.145 - Licensing provisions for the Fixed-Satellite Service in the 20/30 GHz bands.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 47 Telecommunication 2 2014-10-01 2014-10-01 false Licensing provisions for the Fixed-Satellite... (CONTINUED) COMMON CARRIER SERVICES SATELLITE COMMUNICATIONS Applications and Licenses Space Stations § 25.145 Licensing provisions for the Fixed-Satellite Service in the 20/30 GHz bands. (a) (b)...

  9. 47 CFR 25.144 - Licensing provisions for the 2.3 GHz satellite digital audio radio service.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 47 Telecommunication 2 2010-10-01 2010-10-01 false Licensing provisions for the 2.3 GHz satellite... (CONTINUED) COMMON CARRIER SERVICES SATELLITE COMMUNICATIONS Applications and Licenses Space Stations § 25.144 Licensing provisions for the 2.3 GHz satellite digital audio radio service. (a)...

  10. 47 CFR 25.145 - Licensing conditions for the Fixed-Satellite Service in the 20/30 GHz bands.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 47 Telecommunication 2 2010-10-01 2010-10-01 false Licensing conditions for the Fixed-Satellite... (CONTINUED) COMMON CARRIER SERVICES SATELLITE COMMUNICATIONS Applications and Licenses Space Stations § 25.145 Licensing conditions for the Fixed-Satellite Service in the 20/30 GHz bands. (a) Except...

  11. Satellite Communications with NRAO Green Bank Antennas

    NASA Astrophysics Data System (ADS)

    Ford, John M.; Ford, H. Alyson; Watts, Galen

    2014-11-01

    The National Radio Astronomy Observatory's Green Bank facility has several medium and large antennas that are available for satellite communications. The 100 meter Robert C. Byrd Green Bank Telescope (GBT), the largest and most sensitive antenna on site, is capable of receiving signals at frequencies as high as 86 GHz. In addition to the GBT are the fully operational 43 meter, 20 meter, and 13.7 meter antennas, and three mothballed 26 meter antennas. A transmitter could be fitted to any of these antennas for spacecraft uplinks. We discuss the characteristics of these antennas and possible operational models for future planetary science mission support.

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

    NASA Technical Reports Server (NTRS)

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

    1988-01-01

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

  13. 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.

  14. NATO III satellite communications system control

    NASA Astrophysics Data System (ADS)

    Sanli, N.; Lo, S. C.; Kota, S. L.; Aronson, M. H.

    1984-04-01

    The System Control concepts to improve channel utilization and the recent progress of the design, development and integration of the Control Subsystem for the NATO III network are reported. The network operates with a large number of single destination TDM/QPSK/FDMA carriers to provide voice, low speed telegraph and medium speed data circuits. A power control algorithm to keep the link quality at the desired nominal level as well as improve satellite capacity and a traffic control algorithm allowing reconfiguration of the network to accommodate fluctuating traffic are presented. The System Control Software development cycle, consisting of top level design, which includes functional decomposition and software module structure, detailed design, integration and testing phases, is discussed. Various functional flow diagrams are provided illustrating the information interfaces to external communications, inter-component communications, the network database and the physical devices. An example illustrating the performance of power control and traffic control software is presented.

  15. A digital simulation of message traffic for natural disaster warning communications satellite

    NASA Technical Reports Server (NTRS)

    Hein, G. F.; Stevenson, S. M.

    1972-01-01

    Various types of weather communications are required to alert industries and the general public about the impending occurrence of tornados, hurricanes, snowstorms, floods, etc. A natural disaster warning satellite system has been proposed for meeting the communications requirements of the National Oceanic and Atmospheric Administration. Message traffic for a communications satellite was simulated with a digital computer in order to determine the number of communications channels to meet system requirements. Poisson inputs are used for arrivals and an exponential distribution is used for service.

  16. On-board processing concepts for future satellite communications systems

    NASA Technical Reports Server (NTRS)

    Brandon, W. T. (editor); White, B. E. (editor)

    1980-01-01

    The initial definition of on-board processing for an advanced satellite communications system to service domestic markets in the 1990's is discussed. An exemplar system with both RF on-board switching and demodulation/remodulation baseband processing is used to identify important issues related to system implementation, cost, and technology development. Analyses of spectrum-efficient modulation, coding, and system control techniques are summarized. Implementations for an RF switch and baseband processor are described. Among the major conclusions listed is the need for high gain satellites capable of handling tens of simultaneous beams for the efficient reuse of the 2.5 GHz 30/20 frequency band. Several scanning beams are recommended in addition to the fixed beams. Low power solid state 20 GHz GaAs FET power amplifiers in the 5W range and a general purpose digital baseband processor with gigahertz logic speeds and megabits of memory are also recommended.

  17. A framework for implementing data services in multi-service mobile satellite systems

    NASA Technical Reports Server (NTRS)

    Ali, Mohammed O.; Leung, Victor C. M.; Spolsky, Andrew I.

    1988-01-01

    Mobile satellite systems being planned for introduction in the early 1990s are expected to be invariably of the multi-service type. Mobile Telephone Service (MTS), Mobile Radio Service (MRS), and Mobile Data Service (MDS) are the major classifications used to categorize the many user applications to be supported. The MTS and MRS services encompass circuit-switched voice communication applications, and may be efficiently implemented using a centralized Demand-Assigned Multiple Access (DAMA) scheme. Applications under the MDS category are, on the other hand, message-oriented and expected to vary widely in characteristics; from simplex mode short messaging applications to long duration, full-duplex interactive data communication and large file transfer applications. For some applications under this service category, the conventional circuit-based DAMA scheme may prove highly inefficient due to the long time required to set up and establish communication links relative to the actual message transmission time. It is proposed that by defining a set of basic bearer services to be supported in MDS and optimizing their transmission and access schemes independent of the MTS and MRS services, the MDS applications can be more efficiently integrated into the multi-service design of mobile satellite systems.

  18. Payload system tradeoffs for mobile communications satellites

    NASA Technical Reports Server (NTRS)

    Moody, H. J.

    1990-01-01

    System level trade-offs carried out during Mobile Satellite (M-SAT) design activities are described. These trade-offs relate to the use of low level beam forming, flexible power and spectrum distribution, and selection of the number of beams to cover the service area. It is shown that antenna performance can be improved by sharing horns between beams using a low level beam forming network (BFN). Additionally, greatly increased power utilization is possible using a hybrid matrix concept to share power between beams.

  19. NASA to launch second business communications satellite

    NASA Technical Reports Server (NTRS)

    1981-01-01

    The two stage Delta 3910 launch vehicle was chosen to place the second small business satellite (SBS-B) into a transfer orbit with an apogee of 36,619 kilometers and a perigee of 167 km, at an inclination of 27.7 degrees to Earth's equator. The firing and separation sequence and the inertial guidance system are described as well as the payload assist module. Facilities and services for tracking and control by NASA, COMSAT, Intelsat, and SBS are outlined and prelaunch operations are summarized.

  20. Engineering calculations for communications satellite systems planning

    NASA Technical Reports Server (NTRS)

    Reilly, C. H.; Levis, C. A.; Buyukdura, O. M.; Mount-Campbell, C. A.

    1986-01-01

    Observed solution times were analyzed for the extended gradient and cyclic coordinate search procedures. The times used in the analysis come from computer runs made during a previously-reported experiment conducted to assess the quality of the solutions to a BSS synthesis problem found by the two search methods. The results of a second experiment with a Fixed Satellite Service (FSS) test problem are also presented. Computational results are summarized for mixed integer programming approaches for solving FSS synthesis problems. A promising heuristic algorithm is described. A synthesis model is discussed for orbital arc allotment optimization. Research plans for the near future are also presented.

  1. 15 CFR 950.8 - Satellite Data Services Division (SDSD).

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 15 Commerce and Foreign Trade 3 2010-01-01 2010-01-01 false Satellite Data Services Division (SDSD... THE ENVIRONMENTAL DATA SERVICE ENVIRONMENTAL DATA AND INFORMATION § 950.8 Satellite Data Services Division (SDSD). The Satellite Data Services Division of the EDIS National Climatic Center...

  2. 15 CFR 950.8 - Satellite Data Services Division (SDSD).

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 15 Commerce and Foreign Trade 3 2013-01-01 2013-01-01 false Satellite Data Services Division (SDSD... THE ENVIRONMENTAL DATA SERVICE ENVIRONMENTAL DATA AND INFORMATION § 950.8 Satellite Data Services Division (SDSD). The Satellite Data Services Division of the EDIS National Climatic Center...

  3. 15 CFR 950.8 - Satellite Data Services Division (SDSD).

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 15 Commerce and Foreign Trade 3 2012-01-01 2012-01-01 false Satellite Data Services Division (SDSD... THE ENVIRONMENTAL DATA SERVICE ENVIRONMENTAL DATA AND INFORMATION § 950.8 Satellite Data Services Division (SDSD). The Satellite Data Services Division of the EDIS National Climatic Center...

  4. 15 CFR 950.8 - Satellite Data Services Division (SDSD).

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 15 Commerce and Foreign Trade 3 2011-01-01 2011-01-01 false Satellite Data Services Division (SDSD... THE ENVIRONMENTAL DATA SERVICE ENVIRONMENTAL DATA AND INFORMATION § 950.8 Satellite Data Services Division (SDSD). The Satellite Data Services Division of the EDIS National Climatic Center...

  5. 15 CFR 950.8 - Satellite Data Services Division (SDSD).

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 15 Commerce and Foreign Trade 3 2014-01-01 2014-01-01 false Satellite Data Services Division (SDSD... THE ENVIRONMENTAL DATA SERVICE ENVIRONMENTAL DATA AND INFORMATION § 950.8 Satellite Data Services Division (SDSD). The Satellite Data Services Division of the EDIS National Climatic Center...

  6. Communications technology satellite: United States experiments and disaster communications applications

    NASA Technical Reports Server (NTRS)

    Donoughe, P.; Hunczak, H. R.; Gurski, G. S.

    1978-01-01

    Ground antennas from 0.6 to 5.0 meters in diameter were used as remote earth terminals by the United States for both wideband (television) and narrowband (voice, data) communication in conjunction with the Canadian Hermes satellite's high power transmitter. Experiments summarized cover teleconferencing and duplex videoconferencing for medical, educational, and civic purposes, as well as the remote interpretation of multilingual broadcasts from the United Nations. The capabilities of the system during real and simulated disasters at airports are assessed. Particular attention is given to miniexperiments for flood control in the Mississippi River basin and in Johnstown, Pennsylvania during the 1977 flood.

  7. A robust signalling system for land mobile satellite services

    NASA Technical Reports Server (NTRS)

    Irish, Dale; Shmith, Gary; Hart, Nick; Wines, Marie

    1989-01-01

    Presented here is a signalling system optimized to ensure expedient call set-up for satellite telephony services in a land mobile environment. In a land mobile environment, the satellite to mobile link is subject to impairments from multipath and shadowing phenomena, which result in signal amplitude and phase variations. Multipath, caused by signal scattering and reflections, results in sufficient link margin to compensate for these variations. Direct signal attenuation caused by shadowing due to buildings and vegetation may result in attenuation values in excess of 10 dB and commonly up to 20 dB. It is not practical to provide a link with sufficient margin to enable communication when the signal is blocked. When a moving vehicle passes these obstacles, the link will experience rapid changes in signal strength due to shadowing. Using statistical models of attenuation as a function of distance travelled, a communication strategy has been defined for the land mobile environment.

  8. National Environmental Satellite, Data, and Information Service

    E-print Network

    's Priorities 7 Hazards, Severe Weather, Watches, Warnings Climate Agriculture Environmental Monitoring Program (DMSP) DMSP is operated by NOAA for the U.S. Air Force Jason-2 altimetry satellite Acquiring Next's mission of Science, Service and Stewardship Weather Ready Nation ·Continuous surveillance for severe

  9. Man-Made Moons: Satellite Communications for Schools.

    ERIC Educational Resources Information Center

    Grayson, Lawrence P.; And Others

    In an effort to prepare teachers for the coming changes in education caused by the rapidly developing communication satellite technology, this monograph offers a non-technical background to this new development. It begins by explaining the importance of such satellites and offers a layman's guide to the technology of satellite systems. It reviews…

  10. Beyond ATS-6: Social Uses of Communications Satellites.

    ERIC Educational Resources Information Center

    Cater, Douglass

    A panel discussion was held to examine the efficacy of the Applications Technology Satellites, powerful communication satellites designed to send quality signals to low-cost ground terminals. The satellites have been used on an experimental basis in rural America, Canada, and India. While the panel generally agreed on the great potential of the…

  11. Satellite communications systems and technology. Volume 2; Site Reports

    NASA Technical Reports Server (NTRS)

    Edelson, Burton I.; Pelton, Joseph N.; Bostian, Carles W.; Brandon, William T.; Chan, Vincent W. S.; Hager, E. Paul; Helm, Neil R.; Jennings, Raymond D.; Kwan, Robert K.; Mahle, Christoph E.; Miller, Edward F.; Riley, Lance

    1993-01-01

    Volume 2 of the final report of the NASA/NSF Panel on Satellite Communications Systems and Technology is presented. It consists of the site reports from the panel's visits to satellite communications facilities and laboratories in Europe, Japan, and Russia.

  12. System architecture for an advanced Canadian communications satellite demonstration mission

    NASA Astrophysics Data System (ADS)

    Takats, P.; Irani, S.

    1992-03-01

    An advanced communications satellite system that provides single hop interconnectivity and interworking for both a personal communications network and an advanced private business network in the Ka and Ku bands respectively, is presented. An overall network perspective is discussed that studies the interface of such an advanced satellite communication system to the terrestrial network in the context of the Open Systems Interconnection model. It is shown that this proposed satellite system can dynamically establish links and efficiently allocate the satellite resource amongst the user terminal population for a mix of data and voice traffic.

  13. SAW based systems for mobile communications satellites

    NASA Technical Reports Server (NTRS)

    Peach, R. C.; Miller, N.; Lee, M.

    1993-01-01

    Modern mobile communications satellites, such as INMARSAT 3, EMS, and ARTEMIS, use advanced onboard processing to make efficient use of the available L-band spectrum. In all of these cases, high performance surface acoustic wave (SAW) devices are used. SAW filters can provide high selectivity (100-200 kHz transition widths), combined with flat amplitude and linear phase characteristics; their simple construction and radiation hardness also makes them especially suitable for space applications. An overview of the architectures used in the above systems, describing the technologies employed, and the use of bandwidth switchable SAW filtering (BSSF) is given. The tradeoffs to be considered when specifying a SAW based system are analyzed, using both theoretical and experimental data. Empirical rules for estimating SAW filter performance are given. Achievable performance is illustrated using data from the INMARSAT 3 engineering model (EM) processors.

  14. Mass and power modeling of communication satellites

    NASA Technical Reports Server (NTRS)

    Price, Kent M.; Pidgeon, David; Tsao, Alex

    1991-01-01

    Analytic estimating relationships for the mass and power requirements for major satellite subsystems are described. The model for each subsystem is keyed to the performance drivers and system requirements that influence their selection and use. Guidelines are also given for choosing among alternative technologies which accounts for other significant variables such as cost, risk, schedule, operations, heritage, and life requirements. These models are intended for application to first order systems analyses, where resources do not warrant detailed development of a communications system scenario. Given this ground rule, the models are simplified to 'smoothed' representation of reality. Therefore, the user is cautioned that cost, schedule, and risk may be significantly impacted where interpolations are sufficiently different from existing hardware as to warrant development of new devices.

  15. Satellite Communications Technology Database. Part 2

    NASA Technical Reports Server (NTRS)

    2001-01-01

    The Satellite Communications Technology Database is a compilation of data on state-of-the-art Ka-band technologies current as of January 2000. Most U.S. organizations have not published much of their Ka-band technology data, and so the great majority of this data is drawn largely from Japanese, European, and Canadian publications and Web sites. The data covers antennas, high power amplifiers, low noise amplifiers, MMIC devices, microwave/IF switch matrices, SAW devices, ASIC devices, power and data storage. The data herein is raw, and is often presented simply as the download of a table or figure from a site, showing specified technical characteristics, with no further explanation.

  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. IEEE TRANSACTIONS ON COMMUNICATIONS, VOL. 46, NO. 3, MARCH 1998 309 Doppler Characterization for LEO Satellites

    E-print Network

    Al-Dhahir, Naofal

    when communicating through low earth orbit (LEO) satellites. This paper deals with the analytic approximation, satellite visibility. I. INTRODUCTION F OR SATELLITE communications through low earth orbit (LEOIEEE TRANSACTIONS ON COMMUNICATIONS, VOL. 46, NO. 3, MARCH 1998 309 Doppler Characterization

  18. Distributed Satellite Communication System Design: First-Order Interactions between System and Network

    E-print Network

    de Weck, Olivier L.

    Distributed Satellite Communication System Design: First-Order Interactions between System to bankruptcy. The upfront capital required to implement a satellite communications system is staggering and performance of a system. Traditionally, the first step toward designing satellite communication systems

  19. INTERNATIONAL JOURNAL OF SATELLITE COMMUNICATIONS AND NETWORKING Int. J. Satell. Commun. Network. 2006; 24:261281

    E-print Network

    INTERNATIONAL JOURNAL OF SATELLITE COMMUNICATIONS AND NETWORKING Int. J. Satell. Commun. Network: 10.1002/sat.841 Turbo-coded APSK modulations design for satellite broadband communications Riccardo phase shift keying (APSK) modulation with application to satellite broadband communications. APSK

  20. 78 FR 31576 - Enforcement Proceeding; Certain Two-Way Global Satellite Communication Devices, System and...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-05-24

    ...Proceeding; Certain Two-Way Global Satellite Communication Devices, System and Components...importation of certain two-way global satellite communication devices, system and components...after importation any two-way global satellite communication devices, system,...

  1. Multichannel demultiplexer/demodulator technologies for future satellite communication systems

    NASA Technical Reports Server (NTRS)

    Ivancic, William D.; Budinger, James M.; Staples, Edward J.; Abramovitz, Irwin; Courtois, Hector A.

    1992-01-01

    NASA-Lewis' Space Electronics Div. supports ongoing research in advanced satellite communication architectures, onboard processing, and technology development. Recent studies indicate that meshed VSAT (very small aperture terminal) satellite communication networks using FDMA (frequency division multiple access) uplinks and TDMA (time division multiplexed) downlinks are required to meet future communication needs. One of the critical advancements in such a satellite communication network is the multichannel demultiplexer/demodulator (MCDD). The progress is described which was made in MCDD development using either acousto-optical, optical, or digital technologies.

  2. Suitability of ANSI standards for quantifying communication satellite system performance

    NASA Technical Reports Server (NTRS)

    Cass, Robert D.

    1988-01-01

    A study on the application of American National Standards X3.102 and X3.141 to various classes of communication satellite systems from the simple analog bent-pipe to NASA's Advanced Communications Technology Satellite (ACTS) is discussed. These standards are proposed as means for quantifying the end-to-end communication system performance of communication satellite systems. An introductory overview of the two standards are given followed by a review of the characteristics, applications, and advantages of using X3.102 and X3.141 to quantify with a description of the application of these standards to ACTS.

  3. On-board processing for future satellite communications systems: Satellite-Routed FDMA

    NASA Astrophysics Data System (ADS)

    Berk, G.; Christopher, P. F.; Hoffman, M.; Jean, P. N.; Rotholz, E.; White, B. E.

    1981-05-01

    A frequency division multiple access (FDMA) 30/20 GHz satellite communications architecture without on-board baseband processing is investigated. Conceptual system designs are suggested for domestic traffic models totaling 4 Gb/s of customer premises service (CPS) traffic and 6 Gb/s of trunking traffic. Emphasis is given to the CPS portion of the system which includes thousands of earth terminals with digital traffic ranging from a single 64 kb/s voice channel to hundreds of channels of voice, data, and video with an aggregate data rate of 33 Mb/s. A unique regional design concept that effectively smooths the non-uniform traffic distribution and greatly simplifies the satellite design is employed. The satellite antenna system forms thirty-two 0.33 deg beam on both the uplinks and the downlinks in one design. In another design matched to a traffic model with more dispersed users, there are twenty-four 0.33 deg beams and twenty-one 0.7 deg beams. Detailed system design techniques show that a single satellite producing approximately 5 kW of dc power is capable of handling at least 75% of the postulated traffic. A detailed cost model of the ground segment and estimated system costs based on current information from manufacturers are presented.

  4. On-board processing for future satellite communications systems: Satellite-Routed FDMA

    NASA Technical Reports Server (NTRS)

    Berk, G.; Christopher, P. F.; Hoffman, M.; Jean, P. N.; Rotholz, E.; White, B. E.

    1981-01-01

    A frequency division multiple access (FDMA) 30/20 GHz satellite communications architecture without on-board baseband processing is investigated. Conceptual system designs are suggested for domestic traffic models totaling 4 Gb/s of customer premises service (CPS) traffic and 6 Gb/s of trunking traffic. Emphasis is given to the CPS portion of the system which includes thousands of earth terminals with digital traffic ranging from a single 64 kb/s voice channel to hundreds of channels of voice, data, and video with an aggregate data rate of 33 Mb/s. A unique regional design concept that effectively smooths the non-uniform traffic distribution and greatly simplifies the satellite design is employed. The satellite antenna system forms thirty-two 0.33 deg beam on both the uplinks and the downlinks in one design. In another design matched to a traffic model with more dispersed users, there are twenty-four 0.33 deg beams and twenty-one 0.7 deg beams. Detailed system design techniques show that a single satellite producing approximately 5 kW of dc power is capable of handling at least 75% of the postulated traffic. A detailed cost model of the ground segment and estimated system costs based on current information from manufacturers are presented.

  5. Rain Fade Compensation Alternatives for Ka Band Communication Satellites

    NASA Technical Reports Server (NTRS)

    Acosta, Roberto J.

    1997-01-01

    Future satellite communications systems operating in Ka-band frequency band are subject to degradation produced by the troposphere which is much more severe than those found at lower frequency bands. These impairments include signal absorption by rain, clouds and gases, and amplitude scintillation's arising from refractive index irregularities. For example, rain attenuation at 20 GHz is almost three times that at 11 GHz. Although some of these impairments can be overcome by oversizing the ground station antennas and high power amplifiers, the current trend is using small (less than 20 inches apertures), low-cost ground stations (less than $1000) that can be easily deployed at user premises. As a consequence, most Ka-band systems are expected to employ different forms of fade mitigation that can be implemented relatively easily and at modest cost. The rain fade mitigation approaches are defined by three types of Ka-band communications systems - a low service rate (less than 1.5 Mb/s), a moderate service rate (1.5 to 6 Mb/s) system and a high service rate (greater than 43 Mb/s) system. The ACTS VSAT network, which includes an adaptive rain fade technique, is an example of a moderate service rate.

  6. Controlling satellite communication system unwanted emissions in congested RF spectrum

    NASA Astrophysics Data System (ADS)

    Olsen, Donald; Heymann, Roger

    2007-09-01

    The International Telecommunication Union (ITU), a United Nations (UN) agency, is the agency that, under an international treaty, sets radio spectrum usage regulations among member nations. Within the United States of America (USA), the organization that sets regulations, coordinates an application for use, and provides authorization for federal government/agency use of the radio frequency (RF) spectrum is the National Telecommunications and Information Administration (NTIA). In this regard, the NTIA defines which RF spectrum is available for federal government use in the USA, and how it is to be used. The NTIA is a component of the United States (U.S.) Department of Commerce of the federal government. The significance of ITU regulations is that ITU approval is required for U.S. federal government/agency permission to use the RF spectrum outside of U.S. boundaries. All member nations have signed a treaty to do so. U.S. federal regulations for federal use of the RF spectrum are found in the Manual of Regulations and Procedures for Federal Radio Frequency Management, and extracts of the manual are found in what is known as the Table of Frequency Allocations. Nonfederal government and private sector use of the RF spectrum within the U.S. is regulated by the Federal Communications Commission (FCC). There is a need to control "unwanted emissions" (defined to include out-of-band emissions, which are those immediately adjacent to the necessary and allocated bandwidth, plus spurious emissions) to preclude interference to all other authorized users. This paper discusses the causes, effects, and mitigation of unwanted RF emissions to systems in adjacent spectra. Digital modulations are widely used in today's satellite communications. Commercial communications sector standards are covered for the most part worldwide by Digital Video Broadcast - Satellite (DVB-S) and digital satellite news gathering (DSNG) evolutions and the second generation of DVB-S (DVB-S2) standard, developed by the European Telecommunications Standards Institute (ETSI). In the USA, the Advanced Television Systems Committee (ATSC) has adopted Europe's DVB-S and DVB-S2 standards for satellite digital transmission. With today's digital modulations, RF spectral side lobes can extend out many times the modulating frequency on either side of the carrier at excessive power levels unless filtered. Higher-order digital modulations include quadrature phase shift keying (QPSK), 8 PSK (8-ary phase shift keying), 16 APSK (also called 12-4 APSK (amplitude phase shift keying)), and 16 QAM (quadrature amplitude modulation); they are key for higher spectrum efficiency to enable higher data rate transmissions in limited available bandwidths. Nonlinear high-power amplifiers (HPAs) can regenerate frequency spectral side lobes on input-filtered digital modulations. The paper discusses technologies and techniques for controlling these spectral side lobes, such as the use of square root raised cosine (SRRC) filtering before or during the modulation process, HPA output power back-off (OPBO), and RF filters after the HPA. Spectral mask specifications are a common method of the NTIA and ITU to define spectral occupancy power limits. They are intended to reduce interference among RF spectrum users by limiting excessive radiation at frequencies beyond the regulatory allocated bandwidth.The focus here is on the communication systems of U.S. government satellites used for space research, space operations, Earth exploration satellite services (EESS), meteorological satellite services (METSATS), and other government services. The 8025 to 8400 megahertz (MHz) X band can be used to illustrate the "unwanted emissions" issue. 8025 to 8400 MHz abuts the 8400 to 8450 MHz band allocated by the NTIA and ITU to space research for space-to-Earth transmissions such as receiving very weak Deep Space Network signals. The views and ideas expressed in this paper are those of the authors and do not necessarily reflect those of The Aerospace Corporation or The National Oceanic and Atmosphe

  7. Satellite Communications for Aeronautical Applications: Recent research and Development Results

    NASA Technical Reports Server (NTRS)

    Kerczewski, Robert J.

    2001-01-01

    Communications systems have always been a critical element in aviation. Until recently, nearly all communications between the ground and aircraft have been based on analog voice technology. But the future of global aviation requires a more sophisticated "information infrastructure" which not only provides more and better communications, but integrates the key information functions (communications, navigation, and surveillance) into a modern, network-based infrastructure. Satellite communications will play an increasing role in providing information infrastructure solutions for aviation. Developing and adapting satellite communications technologies for aviation use is now receiving increased attention as the urgency to develop information infrastructure solutions grows. The NASA Glenn Research Center is actively involved in research and development activities for aeronautical satellite communications, with a key emphasis on air traffic management communications needs. This paper describes the recent results and status of NASA Glenn's research program.

  8. Personal communications via ACTS satellite HBR transponders

    NASA Technical Reports Server (NTRS)

    Fang, Russell J. F.

    1991-01-01

    The concept of a fully meshed network of briefcase-sized terminals is presented for personal communications over Ka-band satellite transponders. In this concept, undesirable double-hop delays are avoided for voice communications. The bandwidth and power resources of the transponder are efficiently shared by users in a simple demand-assigned manner via code-division multiple access (CDMA). Voice, data, and facsimile are statistically multiplexed at each terminal. In order to minimize terminal costs, frequency-precorrected, and level-preadjusted continuous-wave tones are sent from the central network control station in each beam so that the terminals in each down-link beam can use these pilots as references for antenna acquisition and tracking, as reliable frequency sources, and as indicators of signal fade for up-link power control (ULPC). The potential CDMA 'near-far' problem due to up-link fades is mitigated by using ULPC. Quasi-burst mode transmission is employed to minimize the potential clock and pseudorandom number code synchronization.

  9. 47 CFR 80.1185 - Supplemental eligibility for mobile-satellite stations.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ...eligibility for mobile-satellite stations. 80...Telecommunication FEDERAL COMMUNICATIONS COMMISSION (CONTINUED...Installations Mobile-Satellite Stations § 80...proposing to furnish satellite communication services on...

  10. 47 CFR 80.1185 - Supplemental eligibility for mobile-satellite stations.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ...eligibility for mobile-satellite stations. 80...Telecommunication FEDERAL COMMUNICATIONS COMMISSION (CONTINUED...Installations Mobile-Satellite Stations § 80...proposing to furnish satellite communication services on...

  11. 47 CFR 80.1185 - Supplemental eligibility for mobile-satellite stations.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ...eligibility for mobile-satellite stations. 80...Telecommunication FEDERAL COMMUNICATIONS COMMISSION (CONTINUED...Installations Mobile-Satellite Stations § 80...proposing to furnish satellite communication services on...

  12. 47 CFR 80.1185 - Supplemental eligibility for mobile-satellite stations.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ...eligibility for mobile-satellite stations. 80...Telecommunication FEDERAL COMMUNICATIONS COMMISSION (CONTINUED...Installations Mobile-Satellite Stations § 80...proposing to furnish satellite communication services on...

  13. 47 CFR 25.284 - Emergency Call Center Service.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ...284 Telecommunication FEDERAL COMMUNICATIONS COMMISSION (CONTINUED) COMMON CARRIER SERVICES SATELLITE COMMUNICATIONS Technical Operations § 25...Service. (a) Providers of mobile satellite service to...

  14. 47 CFR 25.284 - Emergency Call Center Service.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ...284 Telecommunication FEDERAL COMMUNICATIONS COMMISSION (CONTINUED) COMMON CARRIER SERVICES SATELLITE COMMUNICATIONS Technical Operations § 25...Service. (a) Providers of mobile satellite service to...

  15. The Principle of Navigation Constellation Composed of SIGSO Communication Satellites

    E-print Network

    Ji, Hai-Fu; Ai, Guo-Xiang; Shi, Hu-Li

    2012-01-01

    The Chinese Area Positioning System (CAPS), a navigation system based on GEO communication satellites, was developed in 2002 by astronomers at Chinese Academy of Sciences. Extensive positioning experiments of CAPS have been performed since 2005. On the basis of CAPS, this paper studies the principle of navigation constellation composed of Slightly Inclined Geostationary Orbit (SIGSO) communication satellites. SIGSO satellites are derived from end-of-life Geostationary Orbit (GEO) satellites under inclined orbit operation. Considering the abundant frequency resources of SIGSO satellites, multi-frequency observations could be conducted to enhance the precision of pseudorange measurements and ameliorate the positioning performence. The constellation composed of two GEO satellites and four SIGSO satellites with inclination of 5 degrees can provide the most territory of China with 24-hour maximum PDOP less than 42. With synthetic utilization of the truncated precise (TP) code and physical augmentation factor in fo...

  16. A Hybrid Satellite-Terrestrial Approach to Aeronautical Communication Networks

    NASA Technical Reports Server (NTRS)

    Kerczewski, Robert J.; Chomos, Gerald J.; Griner, James H.; Mainger, Steven W.; Martzaklis, Konstantinos S.; Kachmar, Brian A.

    2000-01-01

    Rapid growth in air travel has been projected to continue for the foreseeable future. To maintain a safe and efficient national and global aviation system, significant advances in communications systems supporting aviation are required. Satellites will increasingly play a critical role in the aeronautical communications network. At the same time, current ground-based communications links, primarily very high frequency (VHF), will continue to be employed due to cost advantages and legacy issues. Hence a hybrid satellite-terrestrial network, or group of networks, will emerge. The increased complexity of future aeronautical communications networks dictates that system-level modeling be employed to obtain an optimal system fulfilling a majority of user needs. The NASA Glenn Research Center is investigating the current and potential future state of aeronautical communications, and is developing a simulation and modeling program to research future communications architectures for national and global aeronautical needs. This paper describes the primary requirements, the current infrastructure, and emerging trends of aeronautical communications, including a growing role for satellite communications. The need for a hybrid communications system architecture approach including both satellite and ground-based communications links is explained. Future aeronautical communication network topologies and key issues in simulation and modeling of future aeronautical communications systems are described.

  17. Ultra high frequency follow-on communications satellite system

    NASA Astrophysics Data System (ADS)

    Hassien, Michael J.

    1992-03-01

    The existing constellation of UHF communications satellites (LEASAT and FLTSAT) provide key command and control links for mobile forces of the DoD and other government agencies. The UHF Follow-On satellite program will provide for a new generation of communications satellites to replace the existing ones as they reach the end of their life cycle beginning in 1992. Continued coverage is required for both peacetime and crisis environments, and must be maintained indefinitely. An eight-satellite UFO constellation (two per coverage area) will replenish the existing FLTSATCOM constellation.

  18. Satellite communications application to Pacific countries above Ku band

    NASA Technical Reports Server (NTRS)

    Iida, Takashi

    1992-01-01

    An application of satellite communications above the Ku band to the Pacific region is described, focusing on: (1) Lightsat system and (2) a high capacity satellite system. A small geostationary satellite system using Ku band for the Federated States of Micronesia is shown as an example. A concept of multi-gigabits/second high capacity communications system using two satellites in the Ka band is described. The onboard bit-by-bit processing is very useful in the low link margin environment due to rain attenuation. These topics were obtained by the Asia Pacific Telecommunications Study granted by NASA conducted by the University of Colorado at Boulder.

  19. A satellite system for land-mobile communications in Europe

    NASA Technical Reports Server (NTRS)

    Bartholome, P.; Rogard, R.

    1988-01-01

    There exists a great unsatisified demand for land mobile communications in Europe, particularly in sectors of business activity such as the road transport industry. This demand could best be satisfied by means of satellite-based private networks providing voice and data communications in a hub configuration. The potential market is estimated to encompass several hundred thousand road vehicles and the transmission capacity required would be several thousand channels. ESA is currently demonstrating the potential of satellite communications for this type of application, using a system called PRODAT. System studies are being performed with the aim of defining the architecture of a regional satellite system for Europe.

  20. A satellite system for multimedia personal communications at Ka-band and beyond

    NASA Technical Reports Server (NTRS)

    Vatalaro, F.; Losquadro, G.

    1995-01-01

    The main characteristics of the satellite extremely high frequency (EHF) communication of multimedia mobile services (SECOMS) system are given and the results of the preliminary analysis are included. The SECOMS provides a first generation Ka band system with coverage over Western Europe, in order to satisfy business user needs of very large bandwidths and terminal mobility. The satellite system also provides a second generation EHF enhanced system with increased capacity and enlarged coverage, to serve all of Europe and the nearby countries.

  1. Technology programs and related policies - Impacts on communications satellite business ventures

    NASA Technical Reports Server (NTRS)

    Greenberg, J. S.

    1985-01-01

    The DOMSAT II stochastic communication satellite business venture financial planning simulation model is described. The specification of business scenarios and the results of several analyses are presented. In particular, the impacts of NASA on-orbit propulsion and power technology programs are described. The effects of insurance rates and self-insurance and of the use of the Space Shuttle and Ariane transportation systems on a typical fixed satellite service business venture are discussed.

  2. Enhancing End-to-End Performance of Information Services Over Ka-Band Global Satellite Networks

    NASA Technical Reports Server (NTRS)

    Bhasin, Kul B.; Glover, Daniel R.; Ivancic, William D.; vonDeak, Thomas C.

    1997-01-01

    The Internet has been growing at a rapid rate as the key medium to provide information services such as e-mail, WWW and multimedia etc., however its global reach is limited. Ka-band communication satellite networks are being developed to increase the accessibility of information services via the Internet at global scale. There is need to assess satellite networks in their ability to provide these services and interconnect seamlessly with existing and proposed terrestrial telecommunication networks. In this paper the significant issues and requirements in providing end-to-end high performance for the delivery of information services over satellite networks based on various layers in the OSI reference model are identified. Key experiments have been performed to evaluate the performance of digital video and Internet over satellite-like testbeds. The results of the early developments in ATM and TCP protocols over satellite networks are summarized.

  3. 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.

  4. Engineering calculations for communications satellite systems planning

    NASA Technical Reports Server (NTRS)

    Reilly, Charles H.; Walton, Eric K.; Kohnhorst, Paul

    1987-01-01

    A procedure is described that was used to calculate minimum required satellite separations based on total link carrier to interference requirements. Also summarized are recent results with a switching algorithm for satellite synthesis problems. Analytic solution value bounds for two of the satellite synthesis models studied are described. Preliminary results from an empirical study of alternate mixed integer programming models for satellite synthesis are presented. Research plans for the near future are discussed.

  5. Cockpit weather graphics using mobile satellite communications

    NASA Technical Reports Server (NTRS)

    Seth, Shashi

    1993-01-01

    Many new companies are pushing state-of-the-art technology to bring a revolution in the cockpits of General Aviation (GA) aircraft. The vision, according to Dr. Bruce Holmes - the Assistant Director for Aeronautics at National Aeronautics and Space Administration's (NASA) Langley Research Center, is to provide such an advanced flight control system that the motor and cognitive skills you use to drive a car would be very similar to the ones you would use to fly an airplane. We at ViGYAN, Inc., are currently developing a system called the Pilot Weather Advisor (PWxA), which would be a part of such an advanced technology flight management system. The PWxA provides graphical depictions of weather information in the cockpit of aircraft in near real-time, through the use of broadcast satellite communications. The purpose of this system is to improve the safety and utility of GA aircraft operations. Considerable effort is being extended for research in the design of graphical weather systems, notably the works of Scanlon and Dash. The concept of providing pilots with graphical depictions of weather conditions, overlaid on geographical and navigational maps, is extremely powerful.

  6. An electro-optical communications satellite transponder

    NASA Astrophysics Data System (ADS)

    Goldman, A. M., Jr.

    The design concept of an electrooptical transponder for communications satellites operating in C-band or Ku-band is presented. A system comprising 12 single-polarization transponders 36-MHz wide is illustrated with a block diagram. The RF carrier uplink signal passes through a low-noise GaAs FET amplifier and is translated to the downlink RF frequency by a mixer and local oscillator; this signal then serves as a subcarrier to intensity modulate an 850-nm GaAlAs semiconductor laser, and the optical signal is optically switched via fiber, demodulated by pin diode or avalanche photodiode, and passed through a GaAs FET preamplifier and amplifier for downlink transmission. Both prefiber and postfiber component groups can be integrated onto monolithic electrooptical chips operating at very low power. Additional features and design options are discussed; the frequency variation involved (12 decades) is illustrated; and the optical switching speed is shown to be noncritical in present TDMA, SS/TDMA, or FDMA configurations.

  7. Design and Implementation of a Lunar Communications Satellite and Server for the 2012 SISO Smackdown

    NASA Technical Reports Server (NTRS)

    Bulgatz, Dennis; Heater, Daniel; O'Neal, Daniel A.; Norris, Bryan; Schricker, Bradley C.

    2012-01-01

    Last year, the Simulation Interoperability Standards Organization (SISO) inaugurated the now annual High Level Architecture (HLA) Smackdown at the Spring Simulation Interoperability Workshop (SIW). A primary objective of the Smackdown event is to provide college students with hands-on experience in the High Level Architecture (HLA). The University of Alabama in Huntsville (UAHuntsville) fielded teams in 2011 and 2012. Both the 2011 and 2012 smackdown scenarios were a lunar resupply mission. The 2012 UAHuntsville fielded four federates: a communications network Federate called Lunar Communications and Navigation Satellite Service (LCANServ) for sending and receiving messages, a Lunar Satellite Constellation (LCANSat) to put in place radios needed by the communications network for Line-Of-Sight communication calculations, and 3D graphical displays of the orbiting satellites and a 3D visualization of the lunar surface activities. This paper concentrates on the first two federates by describing the functions, algorithms, the modular FOM, experiences, lessons learned and recommendations for future Smackdown events.

  8. Beyond the Ionosphere: Fifty Years of Satellite Communication

    NASA Technical Reports Server (NTRS)

    Butrica, Andrew J. (Editor)

    1997-01-01

    The three overlapping stages of satellite communications development outlined provide the three-part framework for the organization of the papers contained in this book. Part 1, 'Passive Origins,' treats the first stage of satellite communications development, extending from the 1940s into the early 1960s, when passive artificial and natural satellites funded by the military and private enterprise established the field. Part 2, 'Creating the Global, Regional, and National Systems,' addresses events that constituted the second stage of development. Early in this stage, which stretched from the 1960s into the 1970s, satellite systems began to make their appearance in the United States, while domestic and international efforts sought to bring order to this new but chaotic, field in the form of Comsat and Intelsat. Part 3, 'The Unfolding of the World System,' explores the development of satellite communications in the remainder of the world, with a strong emphasis on Asia.

  9. Alternative force structuring strategies for military satellite communication systems

    NASA Astrophysics Data System (ADS)

    Murdock, William P., Jr.

    1987-12-01

    The purpose of this study was to determine and examine alternative force structuring strategies for military satellite communication (MILSATCOM) systems. The study was undertaken due to the United States' reliance on relatively few, expensive satellites as critical communication links. Current anti-satellite weapons pose a definite threat to missions using this type of strategy. In response to this situation, proliferated MILSATCOM designs using low Earth circular orbits and a highly elliptical (Molniya) orbit were defined and analyzed. The objective of this effort was to compare the proliferated alternative systems' performance and cost with a current MILSATCOM system. The Fleet Satellite Communication (FLTSATCOM) system was used as the baseline system for comparison. Overall, both alternative force structuring strategies provided superior Earth coverage when subjected to satellite losses. This was especially evident in the European and Mideast theaters. The Molyniya constellation was the best alternative when considering system performance, system cost, current MILSATCOM system compatibility and the technology required for system implementation.

  10. [Communication in the health service].

    PubMed

    Panini, Roberta; Fiorini, Fulvio

    2014-01-01

    In the last twenty years, the hospitals have become firms, therefore they have had the necessity to differentiate from each other.Thus, as it is done in the commercial firms, in the health service different formality of communication are studied and introduced in order to attract new consumers and to maintain their trust. Furthermore, due to the introduction of the digitization in the Public Administrations, the communication has become more transparent.A systematic application of communication tools is more and more spread among the Sanitary Firms, whether they are Local Firm or Hospital Firm.Regarding the reference population, communication tools are used with different purposes such as educational and informative. In addition, they are applied as institutional marketing tool, in order to show the offered potentialities and also to increase the level of satisfaction in the patients/consumers who perceive the typology of reception and treatment during the sanitary performance. PMID:25098464

  11. Continuation of the compendium of applications technology satellite and communications technology satellite user experiments 1967-1977, volume 2. [bibliography

    NASA Technical Reports Server (NTRS)

    Engler, N. A.; Nash, J. F.; Strange, J. D.

    1978-01-01

    Approximately 453 reports, papers, and articles catalogued into an information retrieval system, covering communications experiments and demonstrations conducted, utilizing the Communications Technology Satellite and the Applications Technology Satellites 1, 3, 5, and 6 are listed.

  12. The Globalstar satellite cellular communication system design and status

    NASA Astrophysics Data System (ADS)

    Dietrich, Fred J.

    1998-01-01

    The Globalstar cellular communication satellite system is described, including its use of Code Division Multiple Access (CDMA) as the basic modulation scheme. Use of diversity for signal quality, as well as power control, is described. Complex phased arrays on the satellite are also described.

  13. Computer-Aided Communication Satellite System Analysis and Optimization.

    ERIC Educational Resources Information Center

    Stagl, Thomas W.; And Others

    Various published computer programs for fixed/broadcast communication satellite system synthesis and optimization are discussed. The rationale for selecting General Dynamics/Convair's Satellite Telecommunication Analysis and Modeling Program (STAMP) in modified form to aid in the system costing and sensitivity analysis work in the Program on…

  14. Advanced maritime communications technology ship-to-shore satellite link

    NASA Astrophysics Data System (ADS)

    Drissel, R. J.; Miller, J. T.

    1983-01-01

    This report documents the Satellite Link activities of the Advanced Maritime Communications Technology (AMCT) Joint Research and Development Project. The activities are sponsored by the U.S. Maritime Administration and the Military Sealift Command as part of the Fleet Management Technology Program. The successful design, implementation, and testing of a satellite data link are described in detail.

  15. Satellite servicing mission preliminary cost estimation model

    NASA Technical Reports Server (NTRS)

    1987-01-01

    The cost model presented is a preliminary methodology for determining a rough order-of-magnitude cost for implementing a satellite servicing mission. Mission implementation, in this context, encompassess all activities associated with mission design and planning, including both flight and ground crew training and systems integration (payload processing) of servicing hardward with the Shuttle. A basic assumption made in developing this cost model is that a generic set of servicing hardware was developed and flight tested, is inventoried, and is maintained by NASA. This implies that all hardware physical and functional interfaces are well known and therefore recurring CITE testing is not required. The development of the cost model algorithms and examples of their use are discussed.

  16. Use of advanced solar cells for commerical communication satellites

    NASA Astrophysics Data System (ADS)

    Landis, Geoffrey A.; Bailey, Sheila G.

    1995-01-01

    The current generation of communications satellites are located primarily in geosynchronous Earth orbit (GEO). Over the next decade, however, a new generation of communications satellites will be built and launched, designed to provide a world-wide interconnection of portable telephones. For this mission, the satellites must be positioned in lower polar- and near-polar orbits. To provide complete coverage, large numbers of satellites will be required. Because of the required number of satellites decreases as the orbital altitude is increased, fewer satellites would be required if the orbit chosen were raised from Low to intermediate orbit. However, in intermediate orbits, satellites encounter significant radiation due to trapped electrons and protons. Radiation tolerant solar cells may be necessary to make such satellites feasible. We analyze the amount of radiation encountered in low and intermediate polar orbits at altitudes of interest to next-generation communication satellites, calculate the expected degradation for silicon, GaAs, and InP solar cells, and show that the lifetimes can be significantly increased by use of advanced solar cells.

  17. Use of advanced solar cells for commercial communication satellites

    NASA Astrophysics Data System (ADS)

    Bailey, Sheila G.; Landis, Geoffrey A.

    1995-03-01

    The current generation of communications satellites are located primarily in geosynchronous Earth orbit (GEO). Over the next decade, however, a new generation of communications satellites will be built and launched, designed to provide a world-wide interconnection of portable telephones. For this mission, the satellites must be positioned in lower polar and near-polar orbits. To provide complete coverage, large numbers of satellites will be required. Because the required number of satellites decreases as the orbital altitude is increased, fewer satellites would be required if the orbit chosen were raised from low to intermediate orbit. However, in intermediate orbits, satellites encounter significant radiation due to trapped electrons and protons. Radiation tolerant solar cells may be necessary to make such satellites feasible. We analyze the amount of radiation encountered in low and intermediate polar orbits at altitudes of interest to next-generation communication satellites, calculate the expected degradation for silicon, GaAs, and InP solar cells, and show that the lifetimes can be significantly increased by use of advanced solar cells.

  18. Application of advanced on-board processing concepts to future satellite communications systems

    NASA Technical Reports Server (NTRS)

    Katz, J. L.; Hoffman, M.; Kota, S. L.; Ruddy, J. M.; White, B. F.

    1979-01-01

    An initial definition of on-board processing requirements for an advanced satellite communications system to service domestic markets in the 1990's is presented. An exemplar system architecture with both RF on-board switching and demodulation/remodulation baseband processing was used to identify important issues related to system implementation, cost, and technology development.

  19. The optical communication link outage probability in satellite formation flying

    NASA Astrophysics Data System (ADS)

    Arnon, Shlomi; Gill, Eberhard

    2014-02-01

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

  20. Advanced Technologies and Satellite Services for Enhancing Space Surveillance

    NASA Astrophysics Data System (ADS)

    2010-08-01

    Space-based systems are becoming part of our infrastructure and our dependency on space-based services has grown. Therefore, the assured availability and operational readiness of space-based services is essential, undoubtedly. However, satellites are subject to a variety of damaging effects and potential threats. These are mostly caused by an increasingly crowded region of outer space, by space weather including solar events and, unfortunately, even attacks on space systems which are no longer sience fiction as impressively demonstrated in 2007 with the Chinese anti-satellite test and the intercept of USA-193 in 2008. Today, German armed forces use several space services primarily for reconnaissance, communications and navigation. As a matter of fact, Germany`s sovereignty and national security depend on the availability of multiple space services. This led the Federal Ministry of Defence to set up a dedicated military Space Situational Awareness Centre at Kalkar/Uedem, Germany, as a significant contribution to a national preventive security. This paper provides information on a range of technical issues related to space assets that are important for anyone involved in the debate over space security and gives a brief survey of the German SSA program. The paper deals with a subset of feasible man-made threats and its fatal effects on space assets. Furthermore, the preliminary conceptual design of an onboard sensor suitable for the instant detection of the previously described types of threats is presented. Finally, advanced technologies for the near real-time transfer of data are highlighted.

  1. Study of EVA operations associated with satellite services

    NASA Technical Reports Server (NTRS)

    Nash, J. O.; Wilde, R. D.

    1982-01-01

    Extravehicular mobility unit (EMU) factors associated with satellite servicing activities are identified and the EMU improvements necessary to enhance satellite servicing operations are outlined. Areas of EMU capabilities, equipment and structural interfaces, time lines, EMU modifications for satellite servicing, environmental hazards, and crew training are vital to manned Eva/satellite services and as such are detailed. Evaluation of EMU capabilities indicates that the EMU can be used in performing near term, basic satellite servicing tasks; however, satellite servicing is greatly enhanced by incorporating key modifications into the EMU. The servicing missions involved in contamination sensitive payload repair are illustrated. EVA procedures and equipment can be standardized, reducing both crew training time and in orbit operations time. By standardizing and coordinating procedures, mission cumulative time lines fall well within the EMU capability.

  2. Spacecraft IF switch matrix for wideband service applications in 30/20 GHz communications satellite systems: Proof-of-concept model, executive summary

    NASA Technical Reports Server (NTRS)

    Ho, P. T.; Coban, E.; Pelose, J.

    1983-01-01

    The design and development of a unique coupler crossbar 20 x 20 microwave switch matrix are described. The test results of the proof of concept model that meets the requirements for a high speed satellite switched, time division multiple access (SS-TDMA) system are presented.

  3. Destination directed packet switch architecture for a geostationary communication satellite network

    NASA Astrophysics Data System (ADS)

    Ivancic, W. D.; Shalkhauser, M. J.; Bobinsky, E. A.; Soni, N. J.; Quintana, J. A.; Kim, H.; Wagner, P.; Vanderaar, M.

    1992-08-01

    A major effort at NASA/Lewis is to identify and develop critical digital technologies and components that enable new commercial missions or significantly improve the performance, cost efficiency, and/or reliability of existing and planned space comunications systems. NASA envisions the need for low data rate, direct to the user communications services, for data, facsimile, voice, and video conferencing. A report that focuses on destination directed packet switching architectures for geostationary communication satellites is presented.

  4. Destination directed packet switch architecture for a geostationary communication satellite network

    NASA Technical Reports Server (NTRS)

    Ivancic, W. D.; Shalkhauser, M. J.; Bobinsky, E. A.; Soni, N. J.; Quintana, J. A.; Kim, H.; Wagner, P.; Vanderaar, M.

    1992-01-01

    A major effort at NASA/Lewis is to identify and develop critical digital technologies and components that enable new commercial missions or significantly improve the performance, cost efficiency, and/or reliability of existing and planned space comunications systems. NASA envisions the need for low data rate, direct to the user communications services, for data, facsimile, voice, and video conferencing. A report that focuses on destination directed packet switching architectures for geostationary communication satellites is presented.

  5. Engineering calculations for communications satellite systems planning

    NASA Technical Reports Server (NTRS)

    Walton, E.; Aebker, E.; Mata, F.; Reilly, C.

    1991-01-01

    The final phase of a satellite synthesis project is described. Several methods for generating satellite positionings with improved aggregate carrier to interference characteristics were studied. Two general methods for modifying required separation values are presented. Also, two methods for improving aggregate carrier to interference (C/I) performance of given satellite synthesis solutions are presented. A perturbation of the World Administrative Radio Conference (WARC) synthesis is presented.

  6. Aeronautical mobile satellite service: Air traffic control applications

    NASA Technical Reports Server (NTRS)

    Sim, Dave

    1990-01-01

    Canada's history both in aviation and in satellite communications development spans several decades. The introduction of aeronautical mobile satellite communications will serve our requirements for airspace management in areas not served by line-of-sight radio and radar facilities. The ensuing improvements in air safety and operating efficiency are eagerly awaited by the aviation community.

  7. The 18/30 GHz fixed communications system service demand assessment. Volume 1: Executive summary

    NASA Technical Reports Server (NTRS)

    Gabriszeski, T.; Reiner, P.; Rogers, J.; Terbo, W.

    1979-01-01

    The total demand for voice, video, and data communications services, and satellite transmission services at the 4/6 GHz, 12/14 GHz, and 18/30 GHz frequencies is discussed. Major study objectives, overall methodology, results, and general observations about a satellite systems market characteristics and trends are summarized.

  8. A Guide to Satellite Communication. Reports and Papers on Mass Communication Number 66.

    ERIC Educational Resources Information Center

    United Nations Educational, Scientific, and Cultural Organization, Paris (France).

    Basic information about the characteristics, uses, and implications of communication satellites is presented. Characteristics covered include the various types of systems--such as point-to-point, distribution, and broadcasting satellites--and the flexibility, capacity, geographical coverage, cost and disadvantages of satellites. The section on…

  9. Digital satellite communication with on board switching system design criteria and implementation aspects

    NASA Astrophysics Data System (ADS)

    Fromm, H. H.; Bella, L.; Garofalo, G.

    1992-03-01

    Satellite onboard processing (OBP) makes possible signal routing and a more efficient use of system resources, thereby facilitating novel satellite communications services. Attention is presently given to one such concept, which involves the setting up of private digital business networks over areas as extensive as the whole of Europe. These private networks will operate at transmission rates not currently achievable by public networks, and shall permit computer-to-computer connections. The satellite employed uses multiple spot beams in conjunction with OBP; capacity is assigned on demand, and multiple private networks can be operated in parallel under a centralized supervision system.

  10. Communication satellite technology: State of the art and development opportunities

    NASA Technical Reports Server (NTRS)

    Woodford, J. B. (compiler)

    1978-01-01

    Opportunities in communication satellite technology are identified and defined. Factors that tend to limit the ready availability of satellite communication to an increasingly wide group of users are evaluated. Current primary limitations on this wide utilization are the availability of frequency and/or synchronous equatorial satellite positions and the cost of individual user Earth terminals. The former could be ameliorated through the reuse of frequencies, the use of higher frequency bands, and the reduction of antenna side lobes. The latter limitation requires innovative hardware, design, careful system design, and large scale production.

  11. Space transportation, satellite services, and space platforms

    NASA Technical Reports Server (NTRS)

    Disher, J. H.

    1979-01-01

    The paper takes a preview of the progressive development of vehicles for space transportation, satellite services, and orbital platforms. A low-thrust upper stage of either the ion engine or chemical type will be developed to transport large spacecraft and space platforms to and from GEO. The multimission spacecraft, space telescope, and other scientific platforms will require orbital serves going beyond that provided by the Shuttle's remote manipulator system, and plans call for extravehicular activity tools, improved remote manipulators, and a remote manned work station (the cherry picker).

  12. COMMUNICATION SATELLITES FOR EDUCATION, SCIENCE AND CULTURE. REPORTS AND PAPERS ON MASS COMMUNICATION, NO. 53.

    ERIC Educational Resources Information Center

    SCHRAMM, WILBUR

    THE TECHNOLOGY OF COMMUNICATION SATELLITES IS SUFFICIENTLY ADVANCED THAT CONCERNED AGENCIES, SUCH AS UNESCO, SHOULD BEGIN TO PLAN FOR THEIR USE IN EXCHANGE OF DATA, NEWS TRANSMISSION, CULTURAL EXCHANGE, AND EDUCATION. GROUNDWORK IN TECHNOLOGY, IN THE DESIGN OF A SATELLITE COMMUNICATION SYSTEM, IN VALUE JUDGMENTS, IN AGREEMENTS OF COOPERATION AND…

  13. President's Task Force on Communications Policy. Domestic Applications of Communication Satellite Technology. Staff Paper Four.

    ERIC Educational Resources Information Center

    President's Task Force on Communications Policy, Washington, DC.

    A staff paper to the President's Task Force on Communications Policy examines the feasibility of a domestic communications satellite system. Although, with expected technological advancement, satellites may play a significant role in domestic transmission and are economically feasible right now, a number of remaining questions make the…

  14. A satellite-based personal communication system for the 21st century

    NASA Technical Reports Server (NTRS)

    Sue, Miles K.; Dessouky, Khaled; Levitt, Barry; Rafferty, William

    1990-01-01

    Interest in personal communications (PCOMM) has been stimulated by recent developments in satellite and terrestrial mobile communications. A personal access satellite system (PASS) concept was developed at the Jet Propulsion Laboratory (JPL) which has many attractive user features, including service diversity and a handheld terminal. Significant technical challenges addressed in formulating the PASS space and ground segments are discussed. PASS system concept and basic design features, high risk enabling technologies, an optimized multiple access scheme, alternative antenna coverage concepts, the use of non-geostationary orbits, user terminal radiation constraints, and user terminal frequency reference are covered.

  15. Leo Satellite Communication through a LEO Constellation using TCP/IP Over ATM

    NASA Technical Reports Server (NTRS)

    Foore, Lawrence R.; Konangi, Vijay K.; Wallett, Thomas M.

    1999-01-01

    The simulated performance characteristics for communication between a terrestrial client and a Low Earth Orbit (LEO) satellite server are presented. The client and server nodes consist of a Transmission Control Protocol /Internet Protocol (TCP/IP) over ATM configuration. The ATM cells from the client or the server are transmitted to a gateway, packaged with some header information and transferred to a commercial LEO satellite constellation. These cells are then routed through the constellation to a gateway on the globe that allows the client/server communication to take place. Unspecified Bit Rate (UBR) is specified as the quality of service (QoS). Various data rates are considered.

  16. R and D limited partnerships (possible applications in advanced communications satellite technology experiment program)

    NASA Technical Reports Server (NTRS)

    1985-01-01

    Typical R&D limited partnership arrangements, advantages and disadvantages of R&D limited partnership (RDLPs) and antitrust and tax implications are described. A number of typical forms of RDLPs are described that may be applicable for use in stimulating R&D and experimental programs using the advanced communications technology satellite. The ultimate goal is to increase the rate of market penetration of goods and/or services based upon advanced satellite communications technology. The conditions necessary for these RDLP forms to be advantageous are outlined.

  17. 78 FR 39200 - Federal Earth Stations-Non-Federal Fixed Satellite Service Space Stations; Spectrum for Non...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-07-01

    ...Stations--Non-Federal Fixed Satellite Service Space Stations; Spectrum for Non-Federal Space Launch Operations AGENCY: Federal Communications...spectrum allocation proposals for three different space related purposes. The Commission makes two...

  18. Evaluation of spacecraft technology programs (effects on communication satellite business ventures), volume 1

    NASA Astrophysics Data System (ADS)

    Greenburg, J. S.; Gaelick, C.; Kaplan, M.; Fishman, J.; Hopkins, C.

    1985-09-01

    Commercial organizations as well as government agencies invest in spacecraft (S/C) technology programs that are aimed at increasing the performance of communications satellites. The value of these programs must be measured in terms of their impacts on the financial performane of the business ventures that may ultimately utilize the communications satellites. An economic evaluation and planning capability was developed and used to assess the impact of NASA on-orbit propulsion and space power programs on typical fixed satellite service (FSS) and direct broadcast service (DBS) communications satellite business ventures. Typical FSS and DBS spin and three-axis stabilized spacecraft were configured in the absence of NASA technology programs. These spacecraft were reconfigured taking into account the anticipated results of NASA specified on-orbit propulsion and space power programs. In general, the NASA technology programs resulted in spacecraft with increased capability. The developed methodology for assessing the value of spacecraft technology programs in terms of their impact on the financial performance of communication satellite business ventures is described. Results of the assessment of NASA specified on-orbit propulsion and space power technology programs are presented for typical FSS and DBS business ventures.

  19. Evaluation of spacecraft technology programs (effects on communication satellite business ventures), volume 1

    NASA Technical Reports Server (NTRS)

    Greenburg, J. S.; Gaelick, C.; Kaplan, M.; Fishman, J.; Hopkins, C.

    1985-01-01

    Commercial organizations as well as government agencies invest in spacecraft (S/C) technology programs that are aimed at increasing the performance of communications satellites. The value of these programs must be measured in terms of their impacts on the financial performane of the business ventures that may ultimately utilize the communications satellites. An economic evaluation and planning capability was developed and used to assess the impact of NASA on-orbit propulsion and space power programs on typical fixed satellite service (FSS) and direct broadcast service (DBS) communications satellite business ventures. Typical FSS and DBS spin and three-axis stabilized spacecraft were configured in the absence of NASA technology programs. These spacecraft were reconfigured taking into account the anticipated results of NASA specified on-orbit propulsion and space power programs. In general, the NASA technology programs resulted in spacecraft with increased capability. The developed methodology for assessing the value of spacecraft technology programs in terms of their impact on the financial performance of communication satellite business ventures is described. Results of the assessment of NASA specified on-orbit propulsion and space power technology programs are presented for typical FSS and DBS business ventures.

  20. Mobile satellite communications from highly inclined elliptic orbits

    NASA Astrophysics Data System (ADS)

    Stuart, J. R.; Norbury, J. A.; Barton, S. K.

    This paper is concerned with the feasibility of developing a commercially profitable land mobile satellite system capable of providing two way voice communications throughout Europe. The traditional Geostationary orbit configuration is compared with two highly inclined elliptical non-GEO orbits; the 12 hour Molniya and 24 hour Tundra. Potentials advantages of elliptical orbits, including resistance to signal fade and blockage and simplicity of a zenith pointing antenna, are assessed against the cost and risks of supporting the two or three satellite constellation necessary to provide continuous 24 hour coverage. Other considerations such as AOCS philosophy, injection strategy, radiation environment and satellite handover strategy are also discussed. The relative merits of the different orbit options are compared in terms of technical performance and overall system cost. The paper concludes that customer needs for low cost reliable mobile voice communications in Europe can best be achieved using a set of communications satellites placed in a highly inclined elliptical orbit.

  1. Satellite services system analysis study. Volume 1: Executive summary

    NASA Technical Reports Server (NTRS)

    1981-01-01

    Service requirements are considered. Topics include development of on-orbit operations scenarios, service equipment summary, crew interaction, and satellite features facilitating servicing. Service equipment concepts are considered. Topics include payload deployment, close proximity retrieval, on-orbit servicing, backup/contingency, delivery/retrieval of high energy payloads, Earth return, optional service, and advanced capabilities. Program requirements are assessed.

  2. The principle of a navigation constellation composed of SIGSO communication satellites

    NASA Astrophysics Data System (ADS)

    Ji, Hai-Fu; Ma, Li-Hua; Ai, Guo-Xiang; Shi, Hu-Li

    2013-04-01

    The Chinese Area Positioning System (CAPS), a navigation system based on geostationary orbit (GEO) communication satellites, was developed in 2002 by astronomers at Chinese Academy of Sciences. Extensive positioning experiments of CAPS have been performed since 2005. On the basis of CAPS, this paper studies the principle of a navigation constellation composed of slightly inclined geostationary orbit (SIGSO) communication satellites. SIGSO satellites are derived from GEO satellites which are near the end of their operational life by inclined orbit operation. Considering the abundant frequency resources of SIGSO satellites, multi-frequency observations could be conducted to enhance the precision of pseudorange measurements and ameliorate the positioning performance. A constellation composed of two GEO satellites and four SIGSO satellites with an inclination of 5° can provide service to most of the territory of China with a maximum position dilution of precision (PDOP) over 24 h of less than 42. With synthetic utilization of the truncated precise code and a physical augmentation factor in four frequencies, the navigation system with this constellation is expected to obtain comparable positioning performance to that of the coarse acquisition code of the Global Positioning System (GPS). When the new method of code-carrier phase combinations is adopted, the system has the potential to possess commensurate accuracy with the precise code in GPS. Additionally, the copious frequency resources can also be used to develop new anti-interference techniques and integrate navigation and communication.

  3. EHF (28/19 GHz) personal communications satellite terminal development

    NASA Technical Reports Server (NTRS)

    Pike, Corey

    1991-01-01

    The concept of communicating on a personal basis using a small terminal has been investigated globally from many different applications and technology perspectives. Applications range from terrestrial handheld communicators for paging, cellular, zone voice/data networks, etc., to satellite terminals of pocket dimensions for voice/low speed data or similar terminals using larger antennas for VSAT, news gathering (30 cm), and video (1.2 m). A brief status of some developments in the satellite personal communications at CRC will be presented.

  4. 78 FR 70237 - Operation of Wireless Communications Services in the 2.3 GHz Band; Establishment of Rules and...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-11-25

    ...Policies for the Digital Audio Radio Satellite Service in the 2310-2360 MHz Frequency...policies for the Digital Audio Radio Satellite Service in the 2310-2360 MHz Frequency...October 31, 2016. Title: Part 25--Satellite Communications; and part 27--...

  5. Satellite communications provisions on NASA Ames instrumented aircraft platforms for Earth science research/applications

    NASA Technical Reports Server (NTRS)

    Shameson, L.; Brass, J. A.; Hanratty, J. J.; Roberts, A. C.; Wegener, S. S.

    1995-01-01

    Earth science activities at NASA Ames are research in atmospheric and ecosystem science, development of remote sensing and in situ sampling instruments, and their integration into scientific research platform aircraft. The use of satellite communications can greatly extend the capability of these agency research platform aircraft. Current projects and plans involve satellite links on the Perseus UAV and the ER-2 via TDRSS and a proposed experiment on the NASA Advanced Communications Technology Satellite. Provisions for data links on the Perseus research platform, via TDRSS S-band multiple access service, have been developed and are being tested. Test flights at Dryden are planned to demonstrate successful end-to-end data transfer. A Unisys Corp. airborne satcom STARLink system is being integrated into an Ames ER-2 aircraft. This equipment will support multiple data rates up to 43 Mb/s each via the TDRS S Ku-band single access service. The first flight mission for this high-rate link is planned for August 1995. Ames and JPL have proposed an ACTS experiment to use real-time satellite communications to improve wildfire research campaigns. Researchers and fire management teams making use of instrumented aircraft platforms at a prescribed burn site will be able to communicate with experts at Ames, the U.S. Forest Service, and emergency response agencies.

  6. 47 CFR 25.261 - Procedures for avoidance of in-line interference events for Non Geostationary Satellite Orbit...

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ...Network Operations in the Fixed-Satellite Service (FSS) Bands. 25...261 Telecommunication FEDERAL COMMUNICATIONS COMMISSION (CONTINUED) COMMON CARRIER SERVICES SATELLITE COMMUNICATIONS Technical Standards §...

  7. 47 CFR 25.278 - Additional coordination obligation for non-geostationary and geostationary satellite systems in...

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ...frequencies allocated to the fixed-satellite service. 25.278 Section 25.278 Telecommunication FEDERAL COMMUNICATIONS COMMISSION (CONTINUED) COMMON CARRIER SERVICES SATELLITE COMMUNICATIONS Technical Operations §...

  8. 47 CFR 25.278 - Additional coordination obligation for non-geostationary and geostationary satellite systems in...

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ...frequencies allocated to the fixed-satellite service. 25.278 Section 25.278 Telecommunication FEDERAL COMMUNICATIONS COMMISSION (CONTINUED) COMMON CARRIER SERVICES SATELLITE COMMUNICATIONS Technical Operations §...

  9. 47 CFR 25.278 - Additional coordination obligation for non-geostationary and geostationary satellite systems in...

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ...frequencies allocated to the fixed-satellite service. 25.278 Section 25.278 Telecommunication FEDERAL COMMUNICATIONS COMMISSION (CONTINUED) COMMON CARRIER SERVICES SATELLITE COMMUNICATIONS Technical Operations §...

  10. 47 CFR 25.278 - Additional coordination obligation for non-geostationary and geostationary satellite systems in...

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ...frequencies allocated to the fixed-satellite service. 25.278 Section 25.278 Telecommunication FEDERAL COMMUNICATIONS COMMISSION (CONTINUED) COMMON CARRIER SERVICES SATELLITE COMMUNICATIONS Technical Operations §...

  11. 47 CFR 25.261 - Procedures for avoidance of in-line interference events for Non Geostationary Satellite Orbit...

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ...Network Operations in the Fixed Satellite Service (FSS) Bands. 25...261 Telecommunication FEDERAL COMMUNICATIONS COMMISSION (CONTINUED) COMMON CARRIER SERVICES SATELLITE COMMUNICATIONS Technical Standards §...

  12. Land vehicle antennas for satellite mobile communications

    NASA Technical Reports Server (NTRS)

    Haddad, H. A.; Pieper, B. V.; Mckenna, D. B.

    1985-01-01

    The RF performance, size, pointing system, and cost were investigated concepts are: for a mechanically steered 1 x 4 tilted microstrip array, a mechanically steered fixed-beam conformal array, and an electronically steered conformal phased array. Emphasis is on the RF performance of the tilted 1 x 4 antenna array and methods for pointing the various antennas studied to a geosynchronous satellite. An updated version of satellite isolations in a two-satellite system is presented. Cost estimates for the antennas in quantities of 10,000 and 100,000 unites are summarized.

  13. Study of LEO-SAT microwave link for broad-band mobile satellite communication system

    NASA Technical Reports Server (NTRS)

    Fujise, Masayuki; Chujo, Wataru; Chiba, Isamu; Furuhama, Yoji; Kawabata, Kazuaki; Konishi, Yoshihiko

    1993-01-01

    In the field of mobile satellite communications, a system based on low-earth-orbit satellites (LEO-SAT's) such as the Iridium system has been proposed. The LEO-SAT system is able to offer mobile telecommunication services in high-latitude areas. Rain degradation, fading and shadowing are also expected to be decreased when the system is operated at a high elevation angle. Furthermore, the propagation delay generated in the LEO-SAT system is less pronounced than that in the geostationary orbit satellite (GEO-SAT) system and, in voice services, the effect of the delay is almost negligible. We proposed a concept of a broad-band mobile satellite communication system with LEO-SAT's and Optical ISL. In that system, a fixed L-band (1.6/1.5 GHz) multibeam is used to offer narrow band service to the mobile terminals in the entire area covered by a LEO-SAT and steerable Ka-band (30/20 GHz) spot beams are used for the wide band service. In this paper, we present results of a study of LEO-SAT microwave link between a satellite and a mobile terminal for a broad-band mobile satellite communication system. First, the results of link budget calculations are presented and the antennas mounted on satellites are shown. For a future mobile antenna technology, we also show digital beamforming (DBF) techniques. DBF, together with modulation and/or demodulation, is becoming a key technique for mobile antennas with advanced functions such as antenna pattern calibration, correction, and radio interference suppression. In this paper, efficient DBF techniques for transmitting and receiving are presented. Furthermore, an adaptive array antenna system suitable for this LEO-SAT is presented.

  14. Communications Satellites: A Rural Response to the Tyranny of Distance.

    ERIC Educational Resources Information Center

    Jordahl, Gregory

    1989-01-01

    Provides an overview of several current satellites-based instructional systems and assesses their potential role in rural education. Highlights include the Oklahoma Arts and Sciences Teleconferencing Service (ASTS); the Texas Interactive Instructional Network (TI-IN); Washington's Satellite Telecommunications Educational Programming (STEP);…

  15. Communications Satellite Receiver Systems for Public Schools: A Technical Primer.

    ERIC Educational Resources Information Center

    Texas Education Agency, Austin.

    Designed to aid school districts contemplating use of some of the telecommunications services now available by satellite, this document contains information on home satellite receiving dishes (Television Receive-Only--TVROs), which can receive radio signals carrying television, sound, and data. This information includes: some factors involved in…

  16. Teleradiology and telemedicine using the advanced communications technology satellite and international maritime satellite at varying bandwidths

    NASA Astrophysics Data System (ADS)

    de Treville, Robert E.; Scotti, Stephen D.; Williamson, Morgan P.; Olson, Eric J.; Brink, Linda; Isle, Ken; Kafaro, Peter

    1995-05-01

    The United States military gained experience with a deployed telemedicine team and unit during the deployment of United States military troops to Haiti as part of `Operation Uphold Democracy.' Consults were conducted primarily between the 28th combat support hospital in Haiti and Walter Reed Army Medical Center in Washington, D.C. The Advanced Communications Technology Satellite and International Maritime Satellite services were used for telecommunications during the deployment. A total of 30 telemedicine consultations were performed during the deployment. All consultations were conducted prospectively, and data was entered in a database for later review. Treatment plans and plans for patient disposition were recorded prior to consultation. Following completion of the telemedicine consultations, each case was reviewed to determine the impact of the telemedicine consult upon the treatment plan or disposition. Fifty percent of the consultations resulted in a significant modification in the patient's treatment plan. Seventeen percent resulted in a significant or possible change in evacuation planning. The most frequently used consultants were the dermatologists, radiologists, and hand surgeons. This experience demonstrates that telemedicine can be used effectively in a deployed military environment. In addition, the ability to obtain remote consultations does impact upon medical treatment and upon medical evacuation. Having support personnel in the field was found to be an important factor in utilization of the system.

  17. Future large broadband switched satellite communications networks

    NASA Technical Reports Server (NTRS)

    Staelin, D. H.; Harvey, R. R.

    1979-01-01

    Critical technical, market, and policy issues relevant to future large broadband switched satellite networks are summarized. Our market projections for the period 1980 to 2000 are compared. Clusters of switched satellites, in lieu of large platforms, etc., are shown to have significant advantages. Analysis of an optimum terrestrial network architecture suggests the proper densities of ground stations and that link reliabilities 99.99% may entail less than a 10% cost premium for diversity protection at 20/30 GHz. These analyses suggest that system costs increase as the 0.6 power of traffic. Cost estimates for nominal 20/30 GHz satellite and ground facilities suggest optimum system configurations might employ satellites with 285 beams, multiple TDMA bands each carrying 256 Mbps, and 16 ft ground station antennas. A nominal development program is outlined.

  18. 75 FR 5513 - Determination of Rates and Terms for Preexisting Subscription Services and Satellite Digital...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-02-03

    ...Preexisting Subscription Services and Satellite Digital Audio Radio Services AGENCY...governing the rates for the preexisting satellite digital audio radio services' use of...period 2007 through 2012 for preexisting satellite digital audio radio services...

  19. R&D of a Next Generation LEO System for Global Multimedia Mobile Satellite Communications

    NASA Astrophysics Data System (ADS)

    Morikawa, E.; Motoyoshi, S.; Koyama, Y.; Suzuki, R.; Yasuda, Y.

    2002-01-01

    Next-generation LEO System Research Center (NeLS) was formed in the end of 1997 as a research group under the Telecommunications Advancement Organization of Japan, in cooperation with the telecommunications operators, manufacturers, universities and governmental research organization. The aim of this project is to develop new technology for global multimedia mobile satellite communications services with a user data rate around 2Mbps for handy terminals. component of the IMT-2000, and the second generation of the big-LEO systems. In prosecuting this project, two-phase approach, phase 1 and phase 2, is considered. Phase 1 is the system definition and development of key technologies. In Phase 2, we plan to verify the developed technology in Phase 1 on space. From this year we shifted the stage to Phase 2, and are now developing the prototype of on-board communication systems for flight tests, which will be planed at around 2006. The satellite altitude is assumed to be 1200 km in order to reduce the number of satellites, to avoid the Van Allen radiation belts and to increase the minimum elevation angle. Ten of the circular orbits with 55 degree of inclination are selected to cover the earth surface from -70 to 70 degree in latitude. 12 satellites are positioned at regular intervals in each orbit. In this case, the minimum elevation angle from the user terminal can be keep more than 20 degree for the visibility of the satellite, and 15 degree for simultaneous visibility of two satellites. Then, NeLS Research Center was focusing on the development of key technologies as the phase 1 project. Four kinds of key technologies; DBF satellite antenna, optical inter-satellite link system, satellite network technology with on-board ATM switch and variable rate modulation were selected. Satellite Antenna Technology: Development of on-board direct radiating active phased array antenna with digital beam forming technology would be one of the most important breakthroughs for the satellite communication systems. Therefore, the experimental DBF network with 16 radiating elements was developed for confirming a basic signal processing performance. A/D sampled data are processed by using FPGA circuit for beam forming by real-time basis. Optical Inter-Satellite Link Technology: The inter-satellite link (ISL) technology is also important, because the inter-satellite network is essential to realize the low delay network connection for multimedia services. The optical ISL simulator was developed for the study of optical modem and optical tracking mechanism. And the sensitivity of 56 photons/bit at 10-9 of error rate has been achieved by employing the Erbium doped fiber amplifier, polarizing filter and narrow band optical filter. Coude path type, the active universal joint (AUJ) type and two flat mirror type of optical antenna mechanism were developed. Satellite Network Technology: For constructing this optical ISL ring, the utilization of wavelength division multiplexing (WDM) technology is envisaged. By applying WDM technology to the optical intra-orbital ISL, logical mesh connections can be achieved by assigning the appropriate wavelength for the links among satellites. By using inclined orbit, inter-orbital ISL connection can be keep continuously. Therefore, WDM technology is also applicable to the inter-orbital ISL network. The satellite ATM network simulator was developed in order to investigate the effect of delay fluctuation caused by the satellite constellations. This simulator works as real-time basis by using commercial ATM switches and personal computers. This simulator was installed Dijkstra's algorithm to determine satellite routing path in order to minimize the end-to-end delay time from the source terminal to the destination terminal. The satellite IP network simulator has been developed in order to evaluate the congestion of the multimedia traffic. Variable Rate Modulation Technology: Considering the propagation impairments in the mobile conditions, we employ the variable rate transmission, which maintains the communication service

  20. Spread spectrum mobile communication experiment using ETS-V satellite

    NASA Technical Reports Server (NTRS)

    Ikegami, Tetsushi; Suzuki, Ryutaro; Kadowaki, Naoto; Taira, Shinichi; Sato, Nobuyasu

    1990-01-01

    The spread spectrum technique is attractive for application to mobile satellite communications, because of its random access capability, immunity to inter-system interference, and robustness to overloading. A novel direct sequence spread spectrum communication equipment is developed for land mobile satellite applications. The equipment is developed based on a matched filter technique to improve the initial acquisition performance. The data rate is 2.4 kilobits per sec. and the PN clock rate is 2.4552 mega-Hz. This equipment also has a function of measuring the multipath delay profile of land mobile satellite channel, making use of a correlation property of a PN code. This paper gives an outline of the equipment and the field test results with ETS-V satellite.

  1. Computer-aided communication satellite system analysis and optimization

    NASA Technical Reports Server (NTRS)

    Stagl, T. W.; Morgan, N. H.; Morley, R. E.; Singh, J. P.

    1973-01-01

    The capabilities and limitations of the various published computer programs for fixed/broadcast communication satellite system synthesis and optimization are discussed. A satellite Telecommunication analysis and Modeling Program (STAMP) for costing and sensitivity analysis work in application of communication satellites to educational development is given. The modifications made to STAMP include: extension of the six beam capability to eight; addition of generation of multiple beams from a single reflector system with an array of feeds; an improved system costing to reflect the time value of money, growth in earth terminal population with time, and to account for various measures of system reliability; inclusion of a model for scintillation at microwave frequencies in the communication link loss model; and, an updated technological environment.

  2. An adaptive array antenna for mobile satellite communications

    NASA Technical Reports Server (NTRS)

    Milne, Robert

    1990-01-01

    The design of an adaptive array antenna for land vehicle operation and its performance in an operational satellite system is described. Linear and circularly polarized antenna designs are presented. The acquisition and tracking operation of a satellite is described and the effect on the communications signal is discussed. A number of system requirements are examined that have a major impact on the antenna design. The results of environmental, power handling, and RFI testing are presented and potential problems are identified.

  3. Personal communications: An extension to the mobile satellite

    NASA Technical Reports Server (NTRS)

    Epstein, Murray; Draper, Francois

    1990-01-01

    As time progresses, customer demands become far more universal, involving integrated, simple to operate, cost effective services, with technology virtually transparent to the operator. Industry will be in a position of providing the necessary services to meet the subscribers' needs. Our resource based industries, transportation services, and utilities in the more rural and unserviced areas will require quality and affordable services that can only be supplied via satellite. One answer to these needs will be one- and two-way interoperable data messaging.

  4. Development of a mobile satellite communication unit

    NASA Technical Reports Server (NTRS)

    Suzuki, Ryutaro; Ikegami, Tetsushi; Hamamoto, Naokazu; Taguchi, Tetsu; Endo, Nobuhiro; Yamamoto, Osamu; Ichiyoshi, Osamu

    1988-01-01

    A compact 210(W) x 280(H) x 330(D) mm mobile terminal capable of transmitting voice and data through L-band mobile satellites is described. The Voice Codec can convert an analog voice to or from digital codes at rates of 9.6, 8 and 4.8 kb/s by an MPC algorithm. The terminal functions with a single 12 V power supplied vehicle battery. The equipment can operate at any L-band frequency allocated for mobile uses in a full duplex mode and will soon be put into a field test via Japans's ETS-V satellite.

  5. Achieving QoS for TCP Traffic in Satellite Networks with Differentiated Services

    NASA Technical Reports Server (NTRS)

    Durresi, Arjan; Kota, Sastri; Goyal, Mukul; Jain, Raj; Bharani, Venkata

    2001-01-01

    Satellite networks play an indispensable role in providing global Internet access and electronic connectivity. To achieve such a global communications, provisioning of quality of service (QoS) within the advanced satellite systems is the main requirement. One of the key mechanisms of implementing the quality of service is traffic management. Traffic management becomes a crucial factor in the case of satellite network because of the limited availability of their resources. Currently, Internet Protocol (IP) only has minimal traffic management capabilities and provides best effort services. In this paper, we presented a broadband satellite network QoS model and simulated performance results. In particular, we discussed the TCP flow aggregates performance for their good behavior in the presence of competing UDP flow aggregates in the same assured forwarding. We identified several factors that affect the performance in the mixed environments and quantified their effects using a full factorial design of experiment methodology.

  6. The Advanced Communications Technology Satellite (ACTS) capabilities for serving science

    NASA Technical Reports Server (NTRS)

    Meyer, Thomas R.

    1990-01-01

    Results of research on potential science applications of the NASA Advanced Communications Technology Satellite (ACTS) are presented. Discussed here are: (1) general research on communications related issues; (2) a survey of science-related activities and programs in the local area; (3) interviews of selected scientists and associated telecommunications support personnel whose projects have communications requirements; (4) analysis of linkages between ACTS functionality and science user communications activities and modes of operation; and (5) an analysis of survey results and the projection of conclusions to a national scale.

  7. Individual Global Navigation Satellite Systems in the Space Service Volume

    NASA Technical Reports Server (NTRS)

    Force, Dale A.

    2013-01-01

    The use of individual Global Navigation Satellite Services (GPS, GLONASS, Galileo, and Beidou/COMPASS) for the position, navigation, and timing in the Space Service Volume at altitudes of 300 km, 3000 km, 8000 km, 15000 km, 25000 km, 36500km and 70000 km is examined and the percent availability of at least one and at least four satellites is presented.

  8. Technology Development on ISS for Satellite Servicing and Exploration

    NASA Technical Reports Server (NTRS)

    Reed, Benjamin B.

    2015-01-01

    NASA's Satellite Servicing Capabilities Office is utilizing the International Space Station to demonstrate technologies essential to satellite servicing endeavors in support of human exploration and science. Within this presentation, we will discuss the status and implications of three of these technology payloads: Restore-L, Asteroid Redirect Robotic Mission (ARRM), Raven, Robotic Refueling Mission (RRM) Phase 2, and RRM Phase 3.

  9. Interference susceptibility measurements for an MSK satellite communication link

    NASA Technical Reports Server (NTRS)

    Kerczewski, Robert J.; Fujikawa, Gene

    1992-01-01

    The results are presented of measurements of the degradation of an MSK satellite link due to modulated and CW (unmodulated) interference. These measurements were made using a hardware based satellite communication link simulator at NASA-Lewis. The results indicate the amount of bit error rate degradation caused by CW interference as a function of frequency and power level, and the degradation caused by adjacent channel and cochannel modulated interference as a function of interference power level. Results were obtained for both the uplink case (including satellite nonlinearity) and the downlink case (linear channel).

  10. Determination of the Required Number of Randomly Spaced Communication Satellites

    NASA Technical Reports Server (NTRS)

    Bennett, Floyd V.; Coleman, Thomas L.; Houbolt, John C.

    1961-01-01

    An investigation has been made f o r determining the minimum number of passive satellites i n near-earth orbits required t o provide given percentages of communication time between two selected ground stations. The study is limited to the geometrical and probability aspects of the problem. An application of the analysis i s made f o r an assumed transatlantic communication system. The satellites are considered t o be i n circular, randomly spaced orbits with fixed inclination and altitude considered range from 1,000 t o 3,000 statute miles.

  11. Satellite Point-to-Multipoint Services for Information Dissemination: Opportunities and Economics.

    ERIC Educational Resources Information Center

    Casewell, I. E.

    1992-01-01

    Outlines the current status of satellite-delivered narrowcasting services in Europe; identifies potential applications, including electronic publishing and corporate data communications; compares various transmission technologies; and explores economic issues with the aid of a spreadsheet model for the cases of a facsimile broadcast and a weather…

  12. Improving Library Services to Satellite Campuses: The Case of the University of Lethbridge

    ERIC Educational Resources Information Center

    Eva, Nicole C.

    2012-01-01

    A survey was done of instructors at two satellite campuses located at a distance from the main campus of the University of Lethbridge in order to ascertain both utilization and awareness of library resources and services. Results were enlightening, indicating that lack of awareness and communication is one of the biggest obstacles for these…

  13. DS-CDMA satellite diversity reception for personal satellite communication: Downlink performance analysis

    NASA Technical Reports Server (NTRS)

    DeGaudenzi, Riccardo; Giannetti, Filippo

    1995-01-01

    The downlink of a satellite-mobile personal communication system employing power-controlled Direct Sequence Code Division Multiple Access (DS-CDMA) and exploiting satellite-diversity is analyzed and its performance compared with a more traditional communication system utilizing single satellite reception. The analytical model developed has been thoroughly validated by means of extensive Monte Carlo computer simulations. It is shown how the capacity gain provided by diversity reception shrinks considerably in the presence of increasing traffic or in the case of light shadowing conditions. Moreover, the quantitative results tend to indicate that to combat system capacity reduction due to intra-system interference, no more than two satellites shall be active over the same region. To achieve higher system capacity, differently from terrestrial cellular systems, Multi-User Detection (MUD) techniques are likely to be required in the mobile user terminal, thus considerably increasing its complexity.

  14. 76 FR 18759 - Improving Communications Services for Native Nations

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-04-05

    ...FEDERAL COMMUNICATIONS COMMISSION [CG Docket...11-30] Improving Communications Services for Native Nations AGENCY: Federal Communications Commission. ACTION...economic, market entry, communication adoption...

  15. Utilization of photovoltaic for broadband satellite communications in rural area of Thailand

    NASA Astrophysics Data System (ADS)

    Jinayim, Theerawut; Mungkung, Narong; Kasayapanand, Nat

    2013-06-01

    Electricity, Information and Communication Technologies (ICTs) are very important not only in urban areas but also in rural areas. To provide ICTs service in rural areas, sources of electricity and communication infrastructures must be implemented. Electricity is a major condition due to the fact that all electronic devices needed it in order to power on, so that it is impossible to operate any forms of ICTs in areas where the main national grid line is unavailable. Almost rural areas of Thailand where the main national grid line is unavailable have very good sunlight intensity. Photovoltaic is the most effective renewable energy technologies in those areas for meeting electricity needed in areas that are not connected to the main national grid line. In this paper, the efficiency utilization of photovoltaic as source of electricity for broadband satellite communication systems as well as social and economic impact and quality of life of people in rural areas of Thailand are presented. The results show that most rural communities would be able to universally access to the basic telecommunications services such as internet access and public telephone via satellite communication systems. However, in some field case study, broadband internet access via satellite communication may be unnecessary for some rural communities and the most exactly rural communities needed are electricity for household usage and battery charger.

  16. Advanced Communication Technology Satellite (ACTS) multibeam antenna technology verification experiments

    NASA Technical Reports Server (NTRS)

    Acosta, Roberto J.; Larko, Jeffrey M.; Lagin, Alan R.

    1992-01-01

    The Advanced Communication Technology Satellite (ACTS) is a key to reaching NASA's goal of developing high-risk, advanced communications technology using multiple frequency bands to support the nation's future communication needs. Using the multiple, dynamic hopping spot beams, and advanced on board switching and processing systems, ACTS will open a new era in communications satellite technology. One of the key technologies to be validated as part of the ACTS program is the multibeam antenna with rapidly reconfigurable hopping and fixed spot beam to serve users equipped with small-aperature terminals within the coverage areas. The proposed antenna technology experiments are designed to evaluate in-orbit ACTS multibeam antenna performance (radiation pattern, gain, cross pol levels, etc.).

  17. Fault-tolerant onboard digital information switching and routing for communications satellites

    NASA Technical Reports Server (NTRS)

    Shalkhauser, Mary JO; Quintana, Jorge A.; Soni, Nitin J.; Kim, Heechul

    1993-01-01

    The NASA Lewis Research Center is developing an information-switching processor for future meshed very-small-aperture terminal (VSAT) communications satellites. The information-switching processor will switch and route baseband user data onboard the VSAT satellite to connect thousands of Earth terminals. Fault tolerance is a critical issue in developing information-switching processor circuitry that will provide and maintain reliable communications services. In parallel with the conceptual development of the meshed VSAT satellite network architecture, NASA designed and built a simple test bed for developing and demonstrating baseband switch architectures and fault-tolerance techniques. The meshed VSAT architecture and the switching demonstration test bed are described, and the initial switching architecture and the fault-tolerance techniques that were developed and tested are discussed.

  18. Modulation/demodulation techniques for satellite communications. Part 1: Background

    NASA Technical Reports Server (NTRS)

    Omura, J. K.; Simon, M. K.

    1981-01-01

    Basic characteristics of digital data transmission systems described include the physical communication links, the notion of bandwidth, FCC regulations, and performance measurements such as bit rates, bit error probabilities, throughputs, and delays. The error probability performance and spectral characteristics of various modulation/demodulation techniques commonly used or proposed for use in radio and satellite communication links are summarized. Forward error correction with block or convolutional codes is also discussed along with the important coding parameter, channel cutoff rate.

  19. Satellite Technologies and Services: Implications for International Distance Education.

    ERIC Educational Resources Information Center

    Stahmer, Anna

    1987-01-01

    This examination of international distance education and open university applications of communication satellites at the postsecondary level notes activities in less developed countries (LDCs); presents potential models for cooperation; and describes technical systems for distance education, emphasizing satellite technology and possible problems…

  20. Optical deep space communication via relay satellite

    NASA Technical Reports Server (NTRS)

    Gagliardi, R. M.; Vilnrotter, V. A.; Dolinar, S. J., Jr.

    1981-01-01

    The possible use of an optical for high rate data transmission from a deep space vehicle to an Earth-orbiting relay satellite while RF links are envisioned for the relay to Earth link was studied. A preliminary link analysis is presented for initial sizing of optical components and power levels, in terms of achievable data rates and feasible range distances. Modulation formats are restricted to pulsed laser operation, involving bot coded and uncoded schemes. The advantage of an optical link over present RF deep space link capabilities is shown. The problems of acquisition, pointing and tracking with narrow optical beams are presented and discussed. Mathematical models of beam trackers are derived, aiding in the design of such systems for minimizing beam pointing errors. The expected orbital geometry between spacecraft and relay satellite, and its impact on beam pointing dynamics are discussed.

  1. 77 FR 30046 - Ninth Meeting: RTCA Special Committee 222, Inmarsat Aeronautical Mobile Satellite (Route) Services

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-05-21

    ...222, Inmarsat Aeronautical Mobile Satellite (Route) Services...222, Inmarsat Aeronautical Mobile Satellite (Route) Services...222, Inmarsat Aeronautical Mobile Satellite (Route) Services...92-463, 5 U.S.C., App.), notice is hereby...

  2. 77 FR 48584 - Tenth Meeting: RTCA Special Committee 222, Inmarsat Aeronautical Mobile Satellite (Route) Services

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-08-14

    ...222, Inmarsat Aeronautical Mobile Satellite (Route) Services...222, Inmarsat Aeronautical Mobile Satellite (Route) Services...222, Inmarsat Aeronautical Mobile Satellite (Route) Services...92-463, 5 U.S.C., App.), notice is hereby...

  3. 75 FR 39724 - Sixth Meeting-Special Committee 222: Inmarsat Aeronautical Mobile Satellite (Route) Services

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-07-12

    ...Committee 222: Inmarsat Aeronautical Mobile Satellite (Route) Services AGENCY: Federal Aviation...Committee 222: Inmarsat Aeronautical Mobile Satellite (Route) Services meeting...Committee 222: Inmarsat Aeronautical Mobile Satellite (Route) Services. DATES: The...

  4. 75 FR 63534 - Seventh Meeting-Special Committee 222: Inmarsat Aeronautical Mobile Satellite (Route) Services

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-10-15

    ...Committee 222: Inmarsat Aeronautical Mobile Satellite (Route) Services AGENCY: Federal Aviation...Committee 222: Inmarsat Aeronautical Mobile Satellite (Route) Services meeting...Committee 222: Inmarsat Aeronautical Mobile Satellite (Route) Services. DATES: The...

  5. 75 FR 15770 - Fifth Meeting-Special Committee 222: Inmarsat Aeronautical Mobile Satellite (Route) Services

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-03-30

    ...Committee 222: Inmarsat Aeronautical Mobile Satellite (Route) Services AGENCY: Federal Aviation...Committee 222: Inmarsat Aeronautical Mobile Satellite (Route) Services meeting...Committee 222: Inmarsat Aeronautical Mobile Satellite (Route) Services. DATES: The...

  6. The Army's Use of the Advanced Communications Technology Satellite

    NASA Technical Reports Server (NTRS)

    Ilse, Kenneth

    1996-01-01

    Tactical operations require military commanders to be mobile and have a high level of independence in their actions. Communications capabilities providing intelligence and command orders in these tactical situations have been limited to simple voice communications or low-rate narrow bandwidth communications because of the need for immediate reliable connectivity. The Advanced Communications Technology Satellite (ACTS) has brought an improved communications tool to the tactical commander giving the ability to gain access to a global communications system using high data rates and wide bandwidths. The Army has successfully tested this new capability of bandwidth-on-demand and high data rates for commanders in real-world conditions during Operation UPHOLD DEMOCRACY in Haiti during the fall and winter of 1994. This paper examines ACTS use by field commanders and details the success of the ACTS system in support of a wide variety of field condition command functions.

  7. US development and commercialization of a North American mobile satellite service

    NASA Technical Reports Server (NTRS)

    Arnold, Ray J.; Gray, Valerie; Freibaum, Jerry

    1990-01-01

    U.S. policies promoting applications and commercialization of space technology for the 'benefit of mankind,' and emphasis on international competitiveness, formed the basis of NASA's Mobile Satellite (MSAT) R&D and user experiments program to develop a commercial U.S. Mobile Satellite Service. Exemplifying this philosophy, the MSAT program targets the reduction of technical, regulatory, market, and financial risks that inhibit commercialization. The program strategy includes industry and user involvement in developing and demonstrating advanced technologies, regulatory advocacy, and financial incentives to industry. Approximately two decades of NASA's satellite communications development and demonstrations have contributed to the emergence of a new multi-billion dollar industry for land, aeronautical, and maritime mobile communications via satellite. NASA's R&D efforts are now evolving from the development of 'enabling' ground technologies for VHF, UHF, and L-Band mobile terminals, to Ka-Band terminals offering additional mobility and user convenience.

  8. 22 CFR 123.27 - Special licensing regime for export to U.S. allies of commercial communications satellite...

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ...allies of commercial communications satellite components, systems, parts, accessories...allies of commercial communications satellite components, systems, parts, accessories...technical data for commercial communications satellites, and who are so registered...

  9. 77 FR 51045 - Certain Two-Way Global Satellite Communication Devices, System and Components Thereof; Notice of...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-08-23

    ...No. 2907] Certain Two-Way Global Satellite Communication Devices, System and Components...complaint entitled Certain Two-Way Global Satellite Communication Devices, System and Components...United States after importation of certain satellite communication devices, systems....

  10. 22 CFR 123.27 - Special licensing regime for export to U.S. allies of commercial communications satellite...

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    .... allies of commercial communications satellite components, systems, parts, accessories, attachments and... export to U.S. allies of commercial communications satellite components, systems, parts, accessories... associated technical data for commercial communications satellites, and who are so registered with...

  11. 22 CFR 123.27 - Special licensing regime for export to U.S. allies of commercial communications satellite...

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    .... allies of commercial communications satellite components, systems, parts, accessories, attachments and... export to U.S. allies of commercial communications satellite components, systems, parts, accessories... associated technical data for commercial communications satellites, and who are so registered with...

  12. 22 CFR 123.27 - Special licensing regime for export to U.S. allies of commercial communications satellite...

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    .... allies of commercial communications satellite components, systems, parts, accessories, attachments and... export to U.S. allies of commercial communications satellite components, systems, parts, accessories... associated technical data for commercial communications satellites, and who are so registered with...

  13. 22 CFR 123.27 - Special licensing regime for export to U.S. allies of commercial communications satellite...

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    .... allies of commercial communications satellite components, systems, parts, accessories, attachments and... export to U.S. allies of commercial communications satellite components, systems, parts, accessories... associated technical data for commercial communications satellites, and who are so registered with...

  14. 22 CFR 123.27 - Special licensing regime for export to U.S. allies of commercial communications satellite...

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    .... allies of commercial communications satellite components, systems, parts, accessories, attachments and... licensing regime for export to U.S. allies of commercial communications satellite components, systems, parts... and certain associated technical data for commercial communications satellites, and who are...

  15. Space station automation study-satellite servicing, volume 2

    NASA Technical Reports Server (NTRS)

    Meissinger, H. F.

    1984-01-01

    Technology requirements for automated satellite servicing operations aboard the NASA space station were studied. The three major tasks addressed: (1) servicing requirements (satellite and space station elements) and the role of automation; (2) assessment of automation technology; and (3) conceptual design of servicing facilities on the space station. It is found that many servicing functions cloud benefit from automation support; and the certain research and development activities on automation technologies for servicing should start as soon as possible. Also, some advanced automation developments for orbital servicing could be effectively applied to U.S. industrial ground based operations.

  16. The 30/20 GHz fixed communications systems service demand assessment. Volume 2: Main report

    NASA Technical Reports Server (NTRS)

    Gamble, R. B.; Seltzer, H. R.; Speter, K. M.; Westheimer, M.

    1979-01-01

    A forecast of demand for telecommunications services through the year 2000 is presented with particular reference to demand for satellite communications. Estimates of demand are provided for voice, video, and data services and for various subcategories of these services. The results are converted to a common digital measure in terms of terabits per year and aggregated to obtain total demand projections.

  17. Toward a Communications Satellite Network for Humanitarian Relief

    NASA Technical Reports Server (NTRS)

    Burleigh, Scott C.; Birrane, Edward J.

    2011-01-01

    Since the introduction in 2008 of the "Ring Road" concept, proposing a communications satellite network designed to support disadvantaged populations, there have been a number of advances in the underlying technologies, CubeSat picosatellites and Delay-Tolerant Networking. We review the original Ring Road proposal, discuss relevant recent technological progress, and offer some tentative notes on projected cost and performance.

  18. An overview of the Communications Technology Satellite (CTS) project

    NASA Technical Reports Server (NTRS)

    Rapp, W.; Ogden, D.; Wright, D.

    1982-01-01

    The Communications Technology Satellite (CTS) project is reviewed. A technical description of the CTS spacecraft and its cognate hardware and operations is included. A historical treatise of the CTS project is provided. Also presented is an overview of the CTS experiments and demonstrations conducted during the course of the project.

  19. Frequency conversion at earth stations for satellite communications

    NASA Astrophysics Data System (ADS)

    Dorsi, D.; Bonfanti, M.; Franti, L. F.

    Dual IF to RF and RD to IF converters used at ground stations interfacing with communications satellite repeaters are described. The dual conversion converters add frequency agility which permits n-to-1 redundancy of GCE and TDMA transponder hopping. Block diagrams are provided for the microwave ICs and wideband low-phase noise microwave sources installed in the converters.

  20. Radar meteorology for satellite communications and earth sensing. II

    NASA Astrophysics Data System (ADS)

    Schroth, A.

    1984-08-01

    The use of coherent polarization diversity radar for satellite communication and earth sensing is discussed along with the design of such a radar and of the DFVLR cloud radar, now under construction. Block circuit diagrams and polarization spheres are shown. Various design alternatives are compared.

  1. Within compound, looking southeast, Satellite Communications Terminal Building (Building 5771) ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    Within compound, looking southeast, Satellite Communications Terminal Building (Building 5771) to left, Gate House (Building 5764) to right of center - Beale Air Force Base, Perimeter Acquisition Vehicle Entry Phased-Array Warning System, End of Spencer Paul Road, north of Warren Shingle Road (14th Street), Marysville, Yuba County, CA

  2. Applications of Multi Port Amplifier to personal satellite communications

    NASA Technical Reports Server (NTRS)

    Egami, Shunichiro

    1995-01-01

    In personal satellite communications, satellite antenna beam becomes narrow, and number of beams will be thirty to more than one hundred. This paper shows that Multi Port Amplifier is most suitable to multiple beam transmitter for personal communications satellite. It was shown that the single beam coverage area(cell) diameter is determined by personal earth station(PES) eirp, uplink C/No and uplink frequency band. Required number of cells for European or North American regional coverage at FPLMTS uplink frequency band is shown as around 32. It was shown that 32 beams systems will be easily implemented by using 2 set of 16-port MPA. Redundancy to SSPA failure is considered by increasing number of SSPAs. Actual configuration for 16-port MPA are briefly shown. The presented configuration will be easy to implement and the most economical solution.

  3. Application of adaptive antenna techniques to future commercial satellite communication

    NASA Technical Reports Server (NTRS)

    Ersoy, L.; Lee, E. A.; Matthews, E. W.

    1987-01-01

    The purpose of this contract was to identify the application of adaptive antenna technique in future operational commercial satellite communication systems and to quantify potential benefits. The contract consisted of two major subtasks. Task 1, Assessment of Future Commercial Satellite System Requirements, was generally referred to as the Adaptive section. Task 2 dealt with Pointing Error Compensation Study for a Multiple Scanning/Fixed Spot Beam Reflector Antenna System and was referred to as the reconfigurable system. Each of these tasks was further sub-divided into smaller subtasks. It should also be noted that the reconfigurable system is usually defined as an open-loop system while the adaptive system is a closed-loop system. The differences between the open- and closed-loop systems were defined. Both the adaptive and reconfigurable systems were explained and the potential applications of such systems were presented in the context of commercial communication satellite systems.

  4. Concepts for 18/30 GHz satellite communication system, volume 1

    NASA Technical Reports Server (NTRS)

    Jorasch, R.; Baker, M.; Davies, R.; Cuccia, L.; Mitchell, C.

    1979-01-01

    Concepts for 18/30 GHz satellite communication systems are presented. Major terminal trunking as well as direct-to-user configurations were evaluated. Critical technologies in support of millimeter wave satellite communications were determined.

  5. A study and experiment plan for digital mobile communication via satellite

    NASA Technical Reports Server (NTRS)

    Jones, J. J.; Craighill, E. J.; Evans, R. G.; Vincze, A. D.; Tom, N. N.

    1978-01-01

    The viability of mobile communications is examined within the context of a frequency division multiple access, single channel per carrier satellite system emphasizing digital techniques to serve a large population of users. The intent is to provide the mobile users with a grade of service consistant with the requirements for remote, rural (perhaps emergency) voice communications, but which approaches toll quality speech. A traffic model is derived on which to base the determination of the required maximum number of satellite channels to provide the anticipated level of service. Various voice digitalization and digital modulation schemes are reviewed along with a general link analysis of the mobile system. Demand assignment multiple access considerations and analysis tradeoffs are presented. Finally, a completed configuration is described.

  6. Communications satellites in the national and global health care information infrastructure: their role, impact, and issues

    NASA Technical Reports Server (NTRS)

    Zuzek, J. E.; Bhasin, K. B.

    1996-01-01

    Health care services delivered from a distance, known collectively as telemedicine, are being increasingly demonstrated on various transmission media. Telemedicine activities have included diagnosis by a doctor at a remote location, emergency and disaster medical assistance, medical education, and medical informatics. The ability of communications satellites to offer communication channels and bandwidth on demand, connectivity to mobile, remote and under served regions, and global access will afford them a critical role for telemedicine applications within the National and Global Information Infrastructure (NII/GII). The importance that communications satellites will have in telemedicine applications within the NII/GII the differences in requirements for NII vs. GII, the major issues such as interoperability, confidentiality, quality, availability, and costs, and preliminary conclusions for future usability based on the review of several recent trails at national and global levels are presented.

  7. United States societal experiments via the Communications Technology Satellite. [antenna coverage

    NASA Technical Reports Server (NTRS)

    Donoughe, P. L.

    1976-01-01

    The Communications Technology Satellite (CTS) is a cooperative experimental program of the United States and Canadian governments. The CTS uses a high-power transponder at the frequencies of 14/12 GHz for two-way television and voice communication. The United States and Canada have agreed to share equally in the use of CTS. The U.S. program includes a variety of societal experiments. The ground stations for these experiments are located from the Atlantic to the Pacific. The satellite communications capabilities and the antenna coverage for the U.S. are summarized. Emphasis is placed on the U.S. societal experiments in the areas of education, health care, and community and special services; nine separate experiments are discussed.

  8. Land Mobile Satellite Service (LMSS): A conceptual system design and identification of the critical technologies: Part 2: Technical report

    NASA Technical Reports Server (NTRS)

    Naderi, F. (editor)

    1982-01-01

    A conceptual system design for a satellite-aided land mobile service is described. A geostationary satellite which employs a large (55-m) UHF reflector to communicate with small inexpensive user antennas on mobile vehicles is discussed. It is shown that such a satellite system through multiple beam antennas and frequency reuse can provide thousands of radiotelephone and dispatch channels serving hundreds of thousands of users throughout the U.S.

  9. Providing satellite systems for the national weather satellite services.

    NASA Technical Reports Server (NTRS)

    Stroud, W. G.; Press, H.; Stampfl, R. A.

    1973-01-01

    Discussion of cooperative arrangements and agreements among NASA, the Department of Commerce, and other governmental agencies in developing and operating meteorological satellite systems. The development of present interagency agreements and their conditions are discussed along with differences from the usual NASA program introduced by the supplier-client relationship between NASA and NOAA (National Oceanic and Atmospheric Administration).

  10. Extravehicular Crewman Work System (ECWS) study program. Volume 3: Satellite service

    NASA Technical Reports Server (NTRS)

    Wilde, R. C.

    1980-01-01

    The satellite service portion of the Extravehicular Crewman Work System Study defines requirements and service equipment concepts for performing satellite service from the space shuttle orbiter. Both normal and contingency orbital satellite service is required. Service oriented satellite design practices are required to provide on orbit satellite service capability for the wide variety of satellites at the subsystem level. Development of additional satellite service equipment is required. The existing space transportation system provides a limited capability for performing satellite service tasks in the shuttle payload bay area.

  11. Planetary gearbox condition monitoring of ship-based satellite communication antennas using ensemble multiwavelet analysis method

    NASA Astrophysics Data System (ADS)

    Chen, Jinglong; Zhang, Chunlin; Zhang, Xiaoyan; Zi, Yanyang; He, Shuilong; Yang, Zhe

    2015-03-01

    Satellite communication antennas are key devices of a measurement ship to support voice, data, fax and video integration services. Condition monitoring of mechanical equipment from the vibration measurement data is significant for guaranteeing safe operation and avoiding the unscheduled breakdown. So, condition monitoring system for ship-based satellite communication antennas is designed and developed. Planetary gearboxes play an important role in the transmission train of satellite communication antenna. However, condition monitoring of planetary gearbox still faces challenges due to complexity and weak condition feature. This paper provides a possibility for planetary gearbox condition monitoring by proposing ensemble a multiwavelet analysis method. Benefit from the property on multi-resolution analysis and the multiple wavelet basis functions, multiwavelet has the advantage over characterizing the non-stationary signal. In order to realize the accurate detection of the condition feature and multi-resolution analysis in the whole frequency band, adaptive multiwavelet basis function is constructed via increasing multiplicity and then vibration signal is processed by the ensemble multiwavelet transform. Finally, normalized ensemble multiwavelet transform information entropy is computed to describe the condition of planetary gearbox. The effectiveness of proposed method is first validated through condition monitoring of experimental planetary gearbox. Then this method is used for planetary gearbox condition monitoring of ship-based satellite communication antennas and the results support its feasibility.

  12. Two-way communication promote value-added services

    SciTech Connect

    1996-06-01

    This article reviews a number of developments in the efforts of electric utilities to establish two-way communications with their customers in order to develop products and services to fit each customer`s needs. In their efforts, utilities are facing an array of technology, including broadband, radio frequency, cellular, satellite, dial inbound, and power line carrier current. Individual efforts with each technology are noted. In many cases, the utilities are finding that existing cable and telephone companies are powerful allies in their efforts. Finding that their technology is marketable, the electric utilities are also diversifying horizontally and marketing their communications tools to other, both inside and outside of the utility industry.

  13. The advent of land mobile satellite service systems

    NASA Astrophysics Data System (ADS)

    Pattan, Bruno

    1987-09-01

    The FCC has allocated the L-band spectrum to geostationary satellite-based mobile radio, mobile telephone, and other similar services, which will then become available for large numbers of rural and suburban users. An expedient means of increasing capacity involves the use of single channel per carrier, demand-assignment multiple access with voice and frequency reuse via multiple beams, and orbital reuse by means of multiple satellites. Attention is given to several of the operational, systematic, and technological considerations of the first generation of land mobile satellite services furnishing thin-route services throughout North America.

  14. Optimizing Satellite Communications With Adaptive and Phased Array Antennas Mary Ann Ingram

    E-print Network

    Ingram, Mary Ann

    Optimizing Satellite Communications With Adaptive and Phased Array Antennas Mary Ann Ingram the focus of the current project is for a ground station to communicate with only one satellite at a time communication with mul- tiple satellites. Two phased array technologies are being investigated by re- searchers

  15. The Transformational Satellite Communications System (TSAT) is the DoD's next generation geosynchronous sat-

    E-print Network

    Touch, Joe

    1 of 7 ABSTRACT The Transformational Satellite Communications System (TSAT) is the DoD's next the network management approach for the TSAT system, a DoD next generation satellite communications system). The GIG architecture uses satellite communications (SATCOM) to achieve the goals of: real-time "sensor

  16. Space Communications 21 (2007/2008) 6982 69 Satellite system performance assessment for

    E-print Network

    Mailhes, Corinne

    Space Communications 21 (2007/2008) 69­82 69 IOS Press Satellite system performance assessment. Concurrent satellite systems have been proposed for IFE (In-Flight Entertainment) communications, thus. At the same time, an increasing interest in the use of satellite communications for ATC (Air Traffic Control

  17. The Transformational Satellite Communications System (TSAT) is poised to become the DoD's next generation

    E-print Network

    Touch, Joe

    1 of 7 ABSTRACT The Transformational Satellite Communications System (TSAT) is poised to become, as well as providing security at physical and link layer. I. INTRODUCTION Satellite communications, the US Government has a history of deploying pro- tected satellite communications systems, beginning

  18. Neuronal somatic ATP release triggers neuron satellite glial cell communication in dorsal

    E-print Network

    Newman, Eric A.

    Neuronal somatic ATP release triggers neuron­ satellite glial cell communication in dorsal root activates P2X7 receptors in satellite cells that enwrap each DRG neuron and triggers the communication neuronal somata and thus triggers bidirectional communication between neurons and satellite cells. Results

  19. 77 FR 58579 - Certain Two-Way Global Satellite Communication Devices, System and Components Thereof...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-09-21

    ...337-TA-854] Certain Two-Way Global Satellite Communication Devices, System and Components...importation of certain two-way global satellite communication devices, system and components...importation of certain two-way global satellite communication devices, system and...

  20. 77 FR 58579 - Certain Two-Way Global Satellite Communication Devices, System and Components Thereof...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-09-21

    ... COMMISSION Certain Two-Way Global Satellite Communication Devices, System and Components Thereof; Institution...-way global satellite communication devices, system and components thereof by reason of infringement of... after importation of certain two-way global satellite communication devices, system and...