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1

Privatization of data communication services by domestic satellite in Thailand  

NASA Astrophysics Data System (ADS)

A summary of privatization of satellite communication services in Thailand is presented. A background of satellite communication in Thailand is given. Satellite communication providers, both government and private, are listed. Steps toward privatization and laws governing telecommunications are addressed.

Reowilaisuk, Rianchai

2

Satellite communications for aeronautical and navigation service  

NASA Astrophysics Data System (ADS)

This paper describes the satellite-based systems to be used by the civil aviation community to meet the future communications, navigation and surveillance requirements for air traffic management over oceans and remote land areas, as well as for other aeronautical mobile communications purposes.

Smith, Richard

3

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

Federal Register 2010, 2011, 2012, 2013

...Earth Stations Aboard Aircraft Communicating with Fixed-Satellite Service Geostationary-Orbit Space Stations AGENCY: Federal...Aircraft. FOR FURTHER INFORMATION CONTACT: Andrea Kelly, Satellite Division, International Bureau, FCC, (202)...

2013-03-29

4

Satellite communications experiment for the Ontario air ambulance service  

NASA Astrophysics Data System (ADS)

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.

Butterworth, John S.

1988-05-01

5

Communication satellite applications  

NASA Astrophysics Data System (ADS)

The status and future of the technologies, numbers and services provided by communications satellites worldwide are explored. The evolution of Intelsat satellites and the associated earth terminals toward high-rate all-digital telephony, data, facsimile, videophone, videoconferencing and DBS capabilities are described. The capabilities, services and usage of the Intersputnik, Eutelsat, Arabsat and Palapa systems are also outlined. Domestic satellite communications by means of the Molniya, ANIK, Olympus, Intelsat and Palapa spacecraft are outlined, noting the fast growth of the market and the growing number of different satellite manufacturers. The technical, economic and service definition issues surrounding DBS systems are discussed, along with presently operating and planned maritime and aeronautical communications and positioning systems. Features of search and rescue and tracking, data, and relay satellite systems are summarized, and services offered or which will be offered by every existing or planned communication satellite worldwide are tabulated.

Pelton, Joseph N.

6

Communications services provided by the PACSAT-1, UOSAT-5, and KITSAT-1 amateur radio satellites  

Microsoft Academic Search

While many proposals to provide communications services via low-Earth-orbit (LEO) satellites have been appearing in the literature, engineers, researchers, and experimenters in the amateur radio service have been advancing the state of the art in single LEO store-and-forward satellite design and application. The scope of this paper will be limited to the PACSAT-1, UOSAT-5, and KITSAT-1 satellites, whose primary mission

Robert J. Diersing

1993-01-01

7

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

Federal Register 2010, 2011, 2012, 2013

...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...

2013-03-08

8

Data communications via satellite  

NASA Astrophysics Data System (ADS)

The Americom satellite communications system is described with respect to data service offerings that range from teletype traffic to wideband services in excess of 60 Mbps. Present wideband services are discussed, along with voice bandwidth data, satellite channel delay, bit rate variations, and the commercial wideband data system known as 56 Plus. Attention is given to the forward error correction, TDMA transmission, terminal operation, and piggyback data on TV distribution.

Langhans, R. A.; Mitchell, T. H.

1980-12-01

9

ConeXpress Orbital Life Extension Vehicle - a commercial service for communications satellites  

NASA Astrophysics Data System (ADS)

Telecommunications satellites are designed for useful lives of 10-15 years before they are "junked" when their propellant runs out. This is a waste of huge catital investments, because all or most of the satellites' revenue-generating communications payloads is still functional. The ConeXpress Orbital Life Extension Vehicle is a novel spacecraft that will significantly prolong the operating lives of these valuable satellites. Launched aboard Ariane-5, it is designed to dock with a satellite and operate as an orbital "tugboat", supplying the propulsion, navigation and guidance to keep its host in the proper orbital slot for many years of revenue-earning service.

Caswell, Doug; Visentin, Gianfranco; Ortega, Guillermo; de Kam, Jaap; Nugteren, Paul Robert; Scholten, Han

2006-08-01

10

Definition of a commercial mobile satellite services network to meet DoD communications needs  

Microsoft Academic Search

Commercial-based satellite networks have the potential to provide cost effective communications support for the Department of Defense (DoD's) less critical needs which include administration, logistics, and other support functions. This paper summarizes the definition of a possible multi-vendor Mobile Satellite Services (MSS) network architecture. A determination is presented as to what degree existing and planned commercial MSS systems could satisfy

K. M. Price; R. G. Leamon

1993-01-01

11

Satellite communications today  

NASA Astrophysics Data System (ADS)

Satellites have opened up prospects for the development of communications, television, and radio broadcasting systems. The area of applications of these systems were expanded and possibilities have appeared. The history of the development of commumications systems is discussed along with its advantages and shortcomings. Development prospects are examined. The implementation of the developments will make it possible to raise the technical level of satellite communications systems and to increase the number of services which can be offered to the people by the communications industry, as well as to improve the quality of an individual services for the country, especially its eastern region.

Zubarev, Yu. B.

1987-02-01

12

An introduction to satellite communications  

NASA Astrophysics Data System (ADS)

An expository treatment of the principles and practice of satellite communications is presented. The development of communications satellite services is described, and the evolution of satellites and earth stations to meet changing requirements is reviewed. The physics and geometry of the geostationary orbit and the construction and operation of satellites and launch vehicles are addressed. The essential factors governing the quality of speech, data, and television signals received via satellite are analyzed. Special attention is given to growth areas in satellite communications (including analog television transmission); digital methods of transmission of voice and data; the use of satellites for maritime, aeronautical, and land-mobile communications; and very-small-aperture terminals.

Dalgleish, Don I.

13

Radio determination satellite service  

NASA Astrophysics Data System (ADS)

The capabilities and measured performance of a geosynchronous satellite-based service called the radio determination satellite service (RDSS), which operates at radio frequencies allocated by the International Telecommunications Union (ITU) and is licensed in the United States by the Federal Communications Commission (FCC), are discussed. Plans for both improvement in capability and expansion to nearly global coverage are described. Since RDSS can also provide radio navigation, some comparisons of this service with the Global Positioning System (GPS) are made.

Briskman, Robert D.

1990-07-01

14

Satellite services beyond 1990  

NASA Astrophysics Data System (ADS)

The commercial use of satellite-system services is discussed in terms of the services that can complement high-speed optical cables. The services currently offered are reviewed, and advances in fiber optics are evaluated to determine potential satellite-service markets. The advantages of satellite implementations include large coverage area, network flexibility, direct connections, and both multipoint-to-point and point-to-multipoint connections. Potential applications and services listed include multipoint and multilateral videoconferencing, computer/data communications, universal personal telecommunications, Ka-band bulk data transfer, satellite news gathering, and single-band VSATs. One important conclusion of the present review is that satellite designs should be driven by market/service considerations as opposed to technology.

Mohajeri, M.; Lo, Gerald; Subaran, Frank; Siachinji, Kenneth

1992-03-01

15

Maritime satellite communication and navigation  

Microsoft Academic Search

The contribution of satellite services to improving maritime safety, covering navigation as well as safety and distress communication, is discussed. The availability and accessibility of these services must be ascertained through international agreements. Satellite services will play an essential role for the electronic sea chart display. International carriage requirements and performance standards are necessary for the relevant equipment on board

Peter Ehlers

1992-01-01

16

Maritime satellite communication and navigation  

NASA Astrophysics Data System (ADS)

The contribution of satellite services to improving maritime safety, covering navigation as well as safety and distress communication, is discussed. The availability and accessibility of these services must be ascertained through international agreements. Satellite services will play an essential role for the electronic sea chart display. International carriage requirements and performance standards are necessary for the relevant equipment on board ships. New generic mobile satellite services will also be of relevance for maritime communication. As far as safety and distress communication is concerned, government agreements are necessary.

Ehlers, Peter

1992-07-01

17

Digital communications by satellite  

Microsoft Academic Search

Topics in digital satellite communications are treated extensively for a readership of students or communications system designers acquainted with communications theory fundamentals and random processes. Major parts of the book are: signal quantizing and multiplexing; satellite communications; modulation and coding in distorted channels; worldwide timing by satellite relay. Some specific topics treated include: PCM quantizing, sampling of nonbandlimited signals, delta

J. J. Spilker Jr.

1977-01-01

18

A TDMA satellite communication system for ISDN services-offset QPSK burst modem coupled with high coding gain FEC  

Microsoft Academic Search

The authors propose a time-division multiple-access (TDMA) satellite communication system suitable for integrated services digital network (ISDN) services for both basic interface services and primary interface services. The proposed system offers B-channel transmission lines among telephone offices and subscriber lines for basic and primary interface services. To provide these service economically and efficiently, the proposed system uses an offset QPSK

Shuzo Kato; Masahiro Morikura; Shuji Kubota; Hiroshi Kazama; Kiyoshi Enomoto

1991-01-01

19

Random Communication Satellite Coverage.  

National Technical Information Service (NTIS)

The report develops models for assessing credible satellite failure rates, population densities, coverage probabilities, and outage intervals. These models are interpreted in terms of the present random military communication satellite system. A sufficien...

C. S. Lorens

1967-01-01

20

Compatibility Analysis between Wideband Code Division Multiple Access (WCDMA) Service and Global Mobile Personal Communication by Satellite (GMPCS)  

Microsoft Academic Search

Due to explosive demand for wireless service and limited frequency spectrum resource, an efficient use of frequency spectrum has been a critical issue for making a full use of available frequency bands. In this paper, we analyze the compatibility between wideband code division multiple access (WCDMA) and the global mobile personal communication by satellite (GMPCS) which is investigated by analyzing

Yong-il Oh; Chung Sang Lyu; Seong Teak Oh; Jin Young Kim

2008-01-01

21

IRIDIUM(R) aeronautical satellite communications  

Microsoft Academic Search

The ever-increasing demand to stay in touch, to be able to communicate anywhere and anytime, has created a market for Low Earth Orbit (LEG) satellite communications services such as the Iridium System. The Iridium satellite communications network is being developed to support the needs of the passenger, the cabin crew and the flight crew. Iridium Communications LLC owns a network

P. W. Lemme; S. M. Glenister; A. W. Miller

1998-01-01

22

47 CFR 25.279 - Inter-satellite service.  

Code of Federal Regulations, 2012 CFR

... 2012-10-01 false Inter-satellite service. 25.279 Section 25...CONTINUED) COMMON CARRIER SERVICES SATELLITE COMMUNICATIONS Technical Operations § 25.279 Inter-satellite service. (a) Any satellite...

2012-10-01

23

47 CFR 25.279 - Inter-satellite service.  

Code of Federal Regulations, 2011 CFR

... 2011-10-01 false Inter-satellite service. 25.279 Section 25...CONTINUED) COMMON CARRIER SERVICES SATELLITE COMMUNICATIONS Technical Operations § 25.279 Inter-satellite service. (a) Any satellite...

2011-10-01

24

Operational disaster communications via satellite  

NASA Astrophysics Data System (ADS)

Communications in disaster areas are often disrupted or so overburdened as to be of little value. Prompt restoration of reliable communications is needed to assess the extent of the damage and then to coordinate and distribute supplies to minimize the suffering. Therefore, reliable communications equipment, that can be transported easily, needs to be an integral part of the disaster assessment, relief response, and rehabilitation teams. Since the mid 1970s, a number of responsible organizations have initiated satellite experiments and demonstrations of disaster communications response and restoration. Some of these demonstrations took place at actual disasters, where small ground terminal equipment was transported into ravaged areas and performed life-saving services. However, no coordinated disaster satellite communications system or network is operational at the current time. This paper discusses a proposed operational disaster communications response system, what needs to be implemented, and what barriers and issues need to be resolved before a disaster communications response system can be fully efficient and effective.

Helm, Neil R.; Wright, David

25

Domestic Communications Satellites.  

ERIC Educational Resources Information Center

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…

Network Project Notebook, 1972

1972-01-01

26

Mobile satellite communications for consumers  

NASA Astrophysics Data System (ADS)

The RadioSat system based on MSAT satellites and scheduled for launch in 1994 is described. The RadioSat system will provide integrated communications and navigation services to consumers, including nationwide digital audio broadcasts, data broadcasts, precision navigation, and two-way voice and data communications. Particular attention is given to the MSAT satellite system capabilities and economics. It is concluded that the RadioSat system will be capable of providing a low-cost, highly flexible two-way communications for consumers that can be adapted to various applications.

Noreen, Gary K.

1991-11-01

27

Signals from Communications Satellites.  

ERIC Educational Resources Information Center

|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)|

Thomsen, Volker

1996-01-01

28

Iridium(R) aeronautical satellite communications  

Microsoft Academic Search

The ever-increasing demand to stay in touch, to be able to communicate anywhere and anytime, has created a market for low Earth orbit (LEO) satellite communications services such as the Iridium system. The Iridium satellite communications network is being developed to support the needs of the passenger, the cabin crew and the flight crew for: aeronautical public correspondence (APC); aeronautical

P. W. Lemme; S. M. Glenister; A. W. Miller

1999-01-01

29

Next generation satellite communications networks  

NASA Astrophysics Data System (ADS)

Existing communication satellites are primarily bent pipe systems retransmitting unprocessed signals in a range of reserved frequency bands. Recent flown or planned space experiments employ a new generation of space hardware, involving a high level of signal handling and switching. The decoupling of up and down links through regeneration as well as advanced routing and switching, allow new markets and applications to be economically addressed, as well as enhancements to present services. Two possible services are highlighted in this paper, one an enhancement of current private business services offered in the Ku band. This allows full mesh T1 services to be offered on low cost very small aperture terminals (VSAT). The other utilizes similar on-board technologies, applying them to the Ka band in support of new personal / mobile services. These services require the development of a new generation of regenerative / switching satellites. A possible Canadian service and technology demonstration mission, projected for the 1997 timeframe is described.

Garland, P. J.; Osborne, F. J.

30

Satellite communications technology  

Microsoft Academic Search

The historical basis for today's communications satellite systems is reviewed to show how technology has developed in the global system. Three generations of earth stations are discussed and the form of future stations is explored. Higher frequencies, frequency reuse, spot beams, and digital and time-division techniques are discussed as important emerging communications methods. In the spacecraft area, improved methods of

B. I. Edelson

1976-01-01

31

Laser satellite communications  

Microsoft Academic Search

The basic principles of laser communications and the designing of laser systems are analyzed. Consideration is given to the link equation, the transmitter terminal, antennas, the optical detector, optical modulation formats, deriving error rate data, and signal requirements for acquisition and tracking. The characteristics of some semiconductor laser sources used for satellite communications are examined. The functions of the optical

Morris Katzman

1987-01-01

32

Technology Requirements for Post-1985 Communications Satellites.  

National Technical Information Service (NTIS)

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 demand...

J. E. Burtt C. R. Moe R. V. Elms L. A. Delateur W. C. Sedlacek

1973-01-01

33

International communications via satellite  

NASA Astrophysics Data System (ADS)

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.

McLucas, J. L.

34

Overview of commercial satellite communications  

Microsoft Academic Search

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

G. W. Beakley

1984-01-01

35

Overview of commercial satellite communications  

NASA Astrophysics Data System (ADS)

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.

Beakley, G. W.

1984-07-01

36

Mobile satellite communications  

NASA Astrophysics Data System (ADS)

Mobile satellite communications is placed in a global perspective with attention focused on the various commercial systems currently available and those recently proposed. The technology behind the systems is discussed as well as military applications. Mobiles are also examined in terms of commercial competition and politics.

37

The first European communications satellite ECS1  

Microsoft Academic Search

The development and capabilities of ECS-1, the communications satellite launched on the sixth Ariane flight by ESA in June 1983, for use by the postal systems of the member states (for telephone and special services) and by the television networks, are briefly characterized. The advantages of satellite communications over ground systems are indicated; the TDMA system for telephone traffic is

N. P. Enderberg

1984-01-01

38

Low Earth orbit communications satellite  

NASA Astrophysics Data System (ADS)

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.

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

39

AERONAUTICAL BROADBAND COMMUNICATIONS VIA SATELLITE  

Microsoft Academic Search

The paper discusses various aspects of aeronautical broadband satellite communications (AirCom). A range of applications and services is identified and categorized into the scenarios of in-flight entertainment, in-flight office, telemedicine, flight security, and flight logistics & maintenance. A number of operational and planned AirCom systems are presented. A structured overview of key issues and respective steps for the system design

M. Werner; M. Holzbock

40

Network signalling system design considerations in a multi-service mobile satellite communications system  

NASA Astrophysics Data System (ADS)

The characteristics of the multiservice mobile satellite network signaling system are presented, and possible implementations of its subsystems are proposed in terms of signaling and call setup procedures, and multiple access techniques. Because of the severe L-band propagation environment, it is recommended that signaling messages on the L/Ku band signaling channel be kept to a minimum, and that the majority of signaling exchanges be performed in-band on the assigned voice channel and relayed back to the network control center via the more robust Ku-band signaling subsystem. A number of signaling subnetworks will be needed to efficiently address the service requirements.

Ali, M. O.; Spolsky, A. I.; Leung, V. C. M.

41

SLCSAT (Submarine Laser Communication Satellite) communication system design study  

Microsoft Academic Search

This report summarizes the results of a Lincoln Laboratory study of issues affecting Submarine Laser Communication Satellite (SLCSAT) implementation. The study compares alternative SLCSAT downlink implementations using semiconductor and solid-state lasers in terms of the satellite transmitter power required to provide a given level of communication service. Signal coding is applied to increase transmitter design flexibility by accommodating a wider

S. L. Bernstein; R. S. Bondurant; E. A. Bucher; V. W. Chan; F. G. Walther

1989-01-01

42

On future missions of satellite communications  

NASA Astrophysics Data System (ADS)

This paper describes a view of satellite communications missions in the 1990's. In this connection, 37 missions are surveyed as future communication/broadcast services. The link budgets for each mission are calculated on a reasonable assumption of both a satellite antenna size and a frequency band used. The diversification in the technology requirements for future missions is shown, including the relationship among scale of earth station, frequency, and transmission rate. Finally, candidate missions for the early 1990's communication satellite services are considered.

Iida, T.; Shimoseko, S.; Iwasaki, K.; Shimada, M.

43

Laser satellite communication network-vibration effect and possible solutions  

Microsoft Academic Search

A number of serious consortiums develop satellite communication networks. The objective of these communication projects is to service personal communication users almost everywhere on Earth. The intersatellite links in those projects use microwave radiation as the carrier. Free-space optical communication between satellites networked together can make possible high-speed communication between different places on Earth. Some advantages of an optical communication

SHLOMI ARNON; N. S. Kopeika

1997-01-01

44

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

Code of Federal Regulations, 2012 CFR

...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...

2012-10-01

45

The satellite communications alternative for maritime safety  

NASA Astrophysics Data System (ADS)

The current status of satellite communication technology for maritime users is surveyed, with an emphasis on emergency communication capabilities. Topics addressed include the organizational structure of Inmarsat, the present and planned Inmarsat space segment, the coastal and ship earth stations, the compact Standard-C terminal, the Enhanced Group Call system, and the L-band Satellite Emergency Position Indicating Radio Beacon. Consideration is given to the services available to Standard-C stations, distress and safety communication procedures, and the use of satellite communication to disseminate weather information. The equipment costs for various ship installations are indicated in a table.

Fear, James L.

1988-10-01

46

Small satellites applications - A new perspective in satellite communications  

NASA Astrophysics Data System (ADS)

The relative advantages of exploiting small satellites for communications systems is addressed with attention given to orbital problems and frequency-band management. Current small-satellite projects which propose the use of VHF and UHF bands from 137 MHz to the L-band are listed and examined including Iridium, Orbcomm, and Starsys. These projects are evaluated with emphasis given to launch strategies, service potential, the use of on-board processing, intersatellite links, and multibeam antennas. The long-term perspective on the use of small-satellite systems indicates good market penetration for low-rate data-transmission services, bearer services, and the transmission of educational programs. The costs of the developing programs are analyzed and shown to offer a lower cost per Kbit in terms of launch and deployment. The use of multiple satellites is shown to be of the most value to programs for global communications which require flexibility in terms of future traffic growth.

Ananasso, F.; Rondinelli, G.; Palmucci, P.; Pavesi, B.

1992-03-01

47

Corporate strategies for satellite communications  

NASA Astrophysics Data System (ADS)

Terrestrial and satellite broadcast communications technologies, while clearly providing tremendous benefits in many market sectors, present something of a challenge to the strategic planning bodies in most organizations. This is because there is no existing analog for the services in the organizations' telecommunications networks. The marketplace is therefore a confusing place for such organizations swamped as it is with competing service providers, technologies, and services, and their telecommunications strategies cannot cope with the opportunities because they have been founded on the exploitation of point to point connections. A mechanism for creating and bounding strategies which combines the rigor of structured analysis with a comprehensive categorization of strategic directions which has been successfully used to generate new paneuropean telecommunications strategies is presented.

Birch, David G. W.; Buck, S. Peter

1991-10-01

48

Optical satellite communications in Europe  

NASA Astrophysics Data System (ADS)

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

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

2010-02-01

49

Radiodetermination satellite services and standard  

NASA Astrophysics Data System (ADS)

Technical and operational aspects of radiodetermination satellite services (RDSSs) are examined in a general overview. RDSS is the satellite position-finding and navigation service (with limited alphanumeric message capability) defined by the FCC and ITU for operation at 1.610-1.626 GHz (uplink) and 2.484-2.500 GHz (downlink). The history of RDSS and its relationship to other satellite communication systems are discussed, and consideration is given to RDSS system architectures; space-segment, control-segment, and user-segment design; traffic management and control of non-RDSS interference; and aeronautical, maritime, land-mobile, personal, and special RDSS applications. Diagrams, graphs, and tables of numerical data are provided.

Rothblatt, Martin A.

50

Potential Use of the Australian Satellite Communications System for School of the Air and Enhanced Educational Services. Report Prepared for the Commonwealth/State Advisory Committee on the Educational Use of Communications Technology.  

ERIC Educational Resources Information Center

|This report considers the potential for the use of the Australian Communications Satellite System (ACSS) for the Australian Schools of the Air (SOTAs) and the delivery of enhanced educational services, and develops the concept of all SOTAs operating through one transponder in a national beam. An evolutionary introduction of satellite transmission…

Davies, N. G.; Gillam, J. A.

51

Satellite Applications for Public Service: Project Summaries.  

ERIC Educational Resources Information Center

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…

Lauffer, Sandra; And Others

52

Satellite Applications for Public Service: Project Summaries.  

ERIC Educational Resources Information Center

|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…

Lauffer, Sandra; And Others

53

Satellite communications and amateur radio  

Microsoft Academic Search

Amateur radio use of Radio-1 and Radio-2 satellite communications is described since its beginning in October, 1978, which involves cooperation between DOSAAF and engineering and student design bodies. Second generation satellites Radio-3 and Radio-8 offered the possibility of an expanded system, and much work was done to increase useful life and reliability of space radio communications. Soviet and foreign radio

A. Abolits

1985-01-01

54

Satellite communications availability - launch scheduling  

Microsoft Academic Search

This report considers the scheduling of periodic launches of communications satellites in order to maintain a required level of system availability. Since satellite lifetimes can be described only statistically, availability is described by the probability of having at least A satellites operating in orbit as a function of time. The behavior of this probability is calculated for variations in launch

C. W. Niessen

1975-01-01

55

Inmarsat second generation satellites for mobile communications  

NASA Astrophysics Data System (ADS)

The second-generation satellites of Inmarsat (the International Maritime Satellite Organization) are in the final stage of integration and testing. The satellites will satisfy the needs originated by the rapid expansion of the system and will allow the introduction of new mobile communications services. The essentials of the spacecraft design and the types of services that will be provided using the new satellites are discussed, with particular consideration given to the characteristics of the communications transponder, its design and technology, the requirements and the design solutions, and the most significant communications parameters. Paralleled linearized traveling-wave amplifiers, L-band shaped global direct radiating array antennas, and surface-acoustic-wave channelization filters are being implemented in the system. Passive intermodulation product generation and multipaction are being recognized as design drivers.

Gambaruto, E.; Banks, D. K.; Krinsky, B.

56

Trends in mobile satellite communication  

NASA Astrophysics Data System (ADS)

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.

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

57

Antennas for mobile satellite communications  

NASA Astrophysics Data System (ADS)

A NASA sponsored program, called the Mobile Satellite (MSAT) system, has prompted the development of several innovative antennas at L-band frequencies. In the space segment of the MSAT system, an efficient, light weight, circularly polarized microstrip array that uses linearly polarized elements was developed as a multiple beam reflector feed system. In the ground segment, a low-cost, low-profile, and very efficient microstrip Yagi array was developed as a medium-gain mechanically steered vehicle antenna. Circularly shaped microstrip patches excited at higher-order modes were also developed as low-gain vehicle antennas. A more recent effort called for the development of a 20/30 GHz mobile terminal antenna for future-generation mobile satellite communications. To combat the high insertion loss encountered at 20/30 GHz, series-fed Monolithic Microwave Integrated Circuit (MMIC) microstrip array antennas are currently being developed. These MMIC arrays may lead to the development of several small but high-gain Ka-band antennas for the Personal Access Satellite Service planned for the 2000s.

Huang, John

1991-12-01

58

Interactive multimedia satellite access communications  

Microsoft Academic Search

Recent advances in satellite technology are making possible the development of broadband satellite access (BSA) systems for two-way access to multimedia Internet services. This article provides an overview of BSA systems with an emphasis on resource management and interworking techniques to support IP-based multimedia services. The article draws on collaborative research performed over the past few years as part of

Tho Le-Ngoc; Victor Leung; Peter Takats; Peter Garland

2003-01-01

59

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

Federal Register 2010, 2011, 2012, 2013

...Geostationary-Orbit Space Stations AGENCY...two-way in-flight broadband services...passengers and flight crews aboard commercial airliners and...geostationary-orbit (GSO) space stations operating...Earth-to-space) band shall...radiation. While in flight there is...

2013-03-08

60

Satellite Applications for Public Service: Project Summaries.  

National Technical Information Service (NTIS)

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 Instructio...

S . Lauffer

1979-01-01

61

Power versus stabilization for laser satellite communication.  

PubMed

To establish optical communication between any two satellites, the lines of sight of their optics must be aligned for the duration of the communication. The satellite pointing and tracking systems perform the alignment. The satellite pointing systems vibrate because of tracking noise and mechanical impacts (such as thruster operation, the antenna pointing mechanism, the solar array driver, navigation noise, tracking noise). These vibrations increase the bit error rate (BER) of the communication system. An expression is derived for adaptive transmitter power that compensates for vibration effects in heterodyne laser satellite links. This compensation makes it possible to keep the link BER performance constant for changes in vibration amplitudes. The motivation for constant BER is derived from the requirement for future satellite communication networks with high quality of service. A practical situation of a two-low-Earth-orbit satellite communication link is given. From the results of the example it is seen that the required power for a given BER increases almost exponentially for linear increase in vibration amplitude. PMID:18319913

Arnon, S

1999-05-20

62

Advanced Satellite Communication System.  

National Technical Information Service (NTIS)

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...

E. J. Staples S. Lie

1992-01-01

63

Mobile communication via satellite towards the year 2000  

NASA Astrophysics Data System (ADS)

Recently, mobile communication services are dramatically growing, and there is an ever increasing demand for these services. INMARSAT (International Maritime Satellite Organization) plays a very important role to establish mobile communication networks for ships and airplanes on the global basis. For personal mobile communication, INMARSAT is currently studying INMARSAT-P hand-held terminal in its Project 21. Several mobile satellite communication systems such as IRIDIUM and Globalstar systems are also proposed in order to realize personal communication services towards the 21st century. This paper presents a recent trend of mobile satellite communication systems mainly aiming at the realization of personal communication services. Activities of CCIR (International Radio Consultative Committee) and major results of WARC (World Administrative Radio Conference) '92 are also briefly introduced focusing on mobile satellite matters.

Hirata, Yasuo

64

Delivery of satellite based broadband services  

NASA Astrophysics Data System (ADS)

Availability of speedy communication links to individuals and organizations is essential to keep pace with the business and social requirements of this modern age. While the PCs have been continuously growing in processing speed and memory capabilities, the availability of broadband communication links still has not been satisfactory in many parts of the world. Recognizing the need to give fillip to the growth of broadband services and improve the broadband penetration, the telecom policies of different counties have placed special emphasis on the same. While emphasis is on the use of fiber optic and copper in local loop, satellite communications systems will play an important role in quickly establishing these services in areas where fiber and other communication systems are not available and are not likely to be available for a long time to come. To make satellite communication systems attractive for the wide spread of these services in a cost effective way special emphasis has to be given on factors affecting the cost of the bandwidth and the equipment. As broadband services are bandwidth demanding, use of bandwidth efficient modulation technique and suitable system architecture are some of the important aspects that need to be examined. Further there is a need to re-look on how information services are provided keeping in view the user requirements and broadcast capability of satellite systems over wide areas. This paper addresses some of the aspects of delivering broadband services via satellite taking Indian requirement as an example.

Chandrasekhar, M. G.; Venugopal, D.

2007-06-01

65

Mobile satellite communications systems - Toward global personal communications  

NASA Astrophysics Data System (ADS)

The constraints imposed by the RF environment are reviewed. An overview of present and planned mobile satellite systems is given. Present systems refer to those already in operation, while planned systems refer to those that have authority to offer the services and have either a satellite in orbit or one being built to support the systems. Future directions for mobile satellite communications systems are discussed. One approach emerging is the use of large satellites, with large antennas, operating at much higher carrier frequencies. A second approach is to use low-earth orbiting (LEO) satellites, in order to reduce the path loss. The LEO approach also results in much smaller propagation delays than those experienced with geostationary satellites.

Lodge, John H.

1991-11-01

66

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

Code of Federal Regulations, 2012 CFR

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

2012-10-01

67

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

Code of Federal Regulations, 2012 CFR

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

2012-10-01

68

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)

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.

Snow, Marcellus S.

1989-09-01

69

Emergency Medical Services Communications.  

National Technical Information Service (NTIS)

Four alternative plans are presented for the New River Valley Planning District Emergency Medical Service Communications System. Because a detailed overall Emergency Medical Service (EMS) plan was lacking for the New River area, communications planners de...

1974-01-01

70

Communications satellites versus fiber optics  

NASA Astrophysics Data System (ADS)

Examples of the interfaces encountered in the provision of intercity, long-distance service in the U.S. are examined, and a comparison is conducted of the costs of the Intercity, Long-Distance portion of a single voice circuit derived from either fixed satellite trunking service or fiber optic bulk capacity. It is estimated that by the end of 1988, fiber optic should span the nation connecting New York and Washington with Los Angeles and San Francisco. It is shown that once fiber connects a given pair of cities, it becomes the least costly transmission medium, especially compared to fixed satellite service. Attention is given to equivalent transmission capacities, six providers of fiber optic capacity, a total satellite capacity comparison, an economic lifetime comparison, satellite and fiber optic network maps, satellite city-pair distance and cost matrices, and fiber optic city-pair distance matrices. It is pointed out that certain future CONUS satellite service applications will be inherently invulnerable to terrestrial fiber optics serving fixed routes.

Goldman, A. M., Jr.

71

Free-space optical communication satellite networks-vibration effects and possible solutions  

Microsoft Academic Search

A number of serious consortiums develop satellite communication networks. The objective of these communication projects is to service personal communication users almost everywhere on earth. The inter satellite links in those project use microwave radiation as the carrier. Free space optical communication between satellites networked together can make possible high speed communications between different places on earth. The advantages of

Shlomi Arnon; Norman S. Kopeika

1997-01-01

72

Healthy satellites provide quality service  

NASA Astrophysics Data System (ADS)

The procedures used by Telesat Canada to ensure the performance of Anik satellites is described. At the Satellite Telemetry, Tracking and Command station, each Anik satellite has its own dedicated antenna. Telemetered information from the satellites is received, processed and forwarded to the Satellite Control Center. There the satellite controllers issue all commands to the satellites, and continually monitor the telemetered data. These data, describing the state of health of the satellites, are then analyzed by engineering specialists. The satellites are held in their precise orbital positions by means of specially developed software. The Anik C and D satellites employ travelling wave tube amplifiers (TWTAs) in the transpounder channels. The TWTA saturated flux density (SFD) and equivalent isotropic radiated power (EIRP) are regularly measured and their trends scrutinized. This ensures that customers receive the radio frequency power needed for high-quality service. The satellite electrical power is supplied by the solar cell array and batteries. Power system performance is evaluated regularly to ensure that power is available to operate the required number of TWTAs. In addition to rain-fades, short service interruptions can be caused by high voltage trip-offs of TWTAs, and by electrostatic discharge related anomalies. To minimize these interruptions, Telesat ensures that the satellite controllers are fully trained and prepared for any eventuality, and the relevant operational procedures are continually refined. A fully trained staff of satellite controllers keep interruptions caused by high voltage trip-offs of TWTAs and by electrostatic discharge to a minimum.

Margittai, Paul

73

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

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

2010-10-01

74

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

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

2009-10-01

75

77 FR 77001 - Comprehensive Review of Licensing and Operating Rules for Satellite Services  

Federal Register 2010, 2011, 2012, 2013

...of Licensing and Operating Rules for Satellite Services AGENCY: Federal Communications...CONTACT: William Bell (202) 418-0741, Satellite Division, International Bureau, Federal...of Licensing and Operating Rules for Satellite Services, adopted and released on...

2012-12-31

76

Telecom 1: French domestic communications satellite system  

NASA Astrophysics Data System (ADS)

Services supplied by TELECOM 1, the components of the TELECOM 1 system, the industrial organization, and the project schedule are described. The TELECOM 1 system: provides broadband digital links between companies in France and neighboring states; routes telephone communications and television broadcasts between France and its overseas territories; and handles government communications. A ground control and monitoring station operates the TDMA system and supervises ground station performance, synchronizes the bursts from each station, surveys the repeaters and provides the billing. Three satellites, including one spare, developed from OTS, MARECS and ECS designs, are launched by Ariane.

1981-05-01

77

A demand assignment control in international business satellite communications network  

NASA Astrophysics Data System (ADS)

An experimental system is being developed for use in an international business satellite (IBS) communications network based on demand-assignment (DA) and TDMA techniques. This paper discusses its system design, in particular from the viewpoints of a network configuration, a DA control, and a satellite channel-assignment algorithm. A satellite channel configuration is also presented along with a tradeoff study on transmission rate, HPA output power, satellite resource efficiency, service quality, and so on.

Nohara, Mitsuo; Takeuchi, Yoshio; Takahata, Fumio; Hirata, Yasuo

78

A native IP satellite communications system  

NASA Astrophysics Data System (ADS)

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

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

2004-08-01

79

Defense satellite communications system - Past, present, and future  

NASA Astrophysics Data System (ADS)

This is a critical point in the long history of the Defense Satellite Communications System. This workhorse communications system has developed from the humble beginnings in the 1960s into today's highly capable backbone of U.S. Government Communications. After a long delay these satellites are being launched again and plan to quickly rebuild this critical national asset which has been held together by determination and sweat following the Challenger disaster. The critical issue is what services shall DSCS provide in the future. The process of defining the SHF communications capability of the next generation of these satellites to support the military needs of the next century is under way.

Cook, Robert G.

1992-03-01

80

Vehicle antennas for mobile satellite communications  

NASA Astrophysics Data System (ADS)

Research on and the state of the art of vehicle antennas for mobile satellite communications are reviewed. Particular attention is given to the concept of mobile satellite communication; system requirements for vehicle antennas; antenna systems for communications, navigation, and broadcasting; and future prospects of vehicle antennas. A monolithic microwave integrated circuit active phased array antenna is considered to be a key technology in the future mobile satellite communications.

Ohmori, Shingo

1991-10-01

81

Application of the aeronautical mobile satellite service (AMSS) and the providers of the service  

NASA Astrophysics Data System (ADS)

The paper describes the different potential users of the AMSS, their requirements, and foreseen applications. The AMSS will be provided by several satellite-communication organizations, including INMARSAT, ARINC, SITA, and various national companies. Consideration is given to air-traffic-control services, aircraft operations communication, administrative communication, passenger communication services, and the problem of compatibility among these components.

Brangier, Francis

1991-07-01

82

Power Versus Stabilization for Laser Satellite Communication  

Microsoft Academic Search

To establish optical communication between any two satellites, the lines of sight of their optics must be aligned for the duration of the communication. The satellite pointing and tracking systems perform the alignment. The satellite pointing systems vibrate because of tracking noise and mechanical impacts (such as thruster operation, the antenna pointing mechanism, the solar array driver, navigation noise, tracking

Shlomi Arnon

1999-01-01

83

Commercial satellite communications - Progress and prospects  

Microsoft Academic Search

A description of international and regional communications satellite systems is presented. It is pointed out that the international area of satellite communications is dominated by Intelsat. There are at present two operational satellites in the Atlantic Ocean Region and one each in the Indian and Pacific Ocean Regions. The Intelsat system will see significant growth in the next decade. During

J. V. Harrington

1977-01-01

84

Domestic satellite communications - The Canadian experience  

NASA Astrophysics Data System (ADS)

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.

Golden, D. A.

1980-09-01

85

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

Code of Federal Regulations, 2010 CFR

...non-voice, non-geostationary mobile-satellite service. 25.142 Section 25.142...CONTINUED) COMMON CARRIER SERVICES SATELLITE COMMUNICATIONS Applications and Licenses...non-voice, non-geostationary mobile-satellite service. (a) Space station...

2009-10-01

86

Leasing of specialized military communication satellites  

Microsoft Academic Search

Traditional military procurement of communication satellites is a long-duration high-cost process. Growing demand for these assets and increased budget constraints are driving the investigation and development of alternative acquisition methods. Leasing of communication bandwidth or transponders is an established alternative to procurement in the commercial satellite industry and for some wideband military communication missions. In general, leasing has not existed

Patrick D. Shannon; Daniel W. Kwon; David Eastin

2012-01-01

87

Optical System in Laser Inter-Satellites Communication  

Microsoft Academic Search

We know that Inter-satellites communication is a very important to us. However, real global coverage can only be achieved by satellite systems. Satellites communication is the most important mean of the communication network. The traditional satellites communication and inter-satellites links are built by microwave. Recent years, laser links for inter-satellites communication are becoming more and more important.

Zhou Li; Wen Chuanhua; Liu Baoming

2008-01-01

88

Experiments on aeronautical satellite communications using ETS-V satellite  

Microsoft Academic Search

The world's first aeronautical satellite communication experiments, conducted at L-band frequencies using a commercial aircraft, are described. An airborne antenna with electronically steerable beam and communication equipment was installed in a B-747F freighter flying over transoceanic flight routes. The satellite used in these experiments is the Engineering Test Satellite-Five (ETS-V). During the test period, various experiments, such as antenna pattern

S. Ohmori; Y. Hase; H. Wakana; S. Taira

1992-01-01

89

Aeronautical Mobile Satellite Service (AMSS) test plan  

NASA Astrophysics Data System (ADS)

A test program is described which will be conducted by the Federal Aviation Administration to support the validation of Standards and Recommended Practices being developed for the Aeronautical Mobile Satellite Service by the International Civil Aviation Organization. A description of the Communication Test Facility is also presented which will be used to perform the tests. A brief description is also included of each test to be performed along with setup and data to be recorded.

Sandlin, Sean M.

1991-05-01

90

Communications and Media Services.  

National Technical Information Service (NTIS)

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 broa...

J. W. Mcculla J. F. Kukowski

1990-01-01

91

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

ERIC Educational Resources Information Center

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…

Richmond, J. Murray

92

Satellite-aided mobile communications: Experiments, applications, and prospects  

Microsoft Academic Search

NASA's application technology satellites (ATS) 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, medical emergency, and for commercial uses in the land and maritime transportation industries. The technical success of the experiments and the demonstrated

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

1981-01-01

93

Satellite-aided mobile communications, experiments, applications and prospects  

Microsoft Academic Search

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

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

1980-01-01

94

Satellite services handbook. Interface guidelines  

NASA Astrophysics Data System (ADS)

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.

1983-12-01

95

Satellite, surface, and subsurface optical communications  

Microsoft Academic Search

Optical communication in the atmosphere, space, the marine boundary layer, and underwater are being investigated for a variety of applications. Three classes of optical communications systems will be addressed: OCULT (optical communications using laser transceivers), ELOS (extended line-of-sight) optical communications, and satellite to subsurface optical communications. OCULT is a 10.6 micron high rate reciprocal tracking heterodyne laser communications system designed

G. C. Mooradian

1978-01-01

96

The Mobile Satellite Services Market.  

ERIC Educational Resources Information Center

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…

Anderson, Samuel

97

INMARSAT and the future of mobile satellite services  

NASA Astrophysics Data System (ADS)

This paper reviews the demand for mobile satellite communications and radiodetermination services from the maritime, aviation, and land mobile communities. It briefly examines existing alternatives and the factors that are affecting the growth and development of mobile satellite communications, with particular reference to INMARSAT. Future mobile earth station standards and services are described, as are the key technological developments and challenges which need to be met before mobile satellite services - on aircraft, the smallest of vessels, and land vehicles - become widely available at significantly lower costs than today.

Ghais, Ahmad; Berzins, Guntis; Wright, David

1987-05-01

98

Communications satellite system for Africa  

NASA Astrophysics Data System (ADS)

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

Kriegl, W.; Laufenberg, W.

1980-09-01

99

Telemedicine using mobile satellite communication.  

PubMed

With a view to providing paramedical care within moving vehicles, a telemedicine technique using mobile satellite communication was proposed. With this technique, the diagnosis from a specialist and the emergency care under his/her instructions would be available on the spot without unnecessary delay. The characteristic problems of this technique were identified as: channel capacity, size of the system, reliability of vital sign transmission, real-time operation and electromagnetic interference. Measures against these problems were devised, and their effectiveness was analyzed. A data format was designed and an experimental system was developed. The system can simultaneously transmit a color image, an audio signal, 3 channels ECG and blood pressures from a mobile station to a ground station. It can transmit an audio signal and error control signals from a ground station to a mobile station in a full duplex mode. Fundamental transmission characteristics were measured in a fixed station. Finally, experiments of medical data transmission were conducted with a navigating ship and an aircraft flying an international route. The measured threshold values of C/N(o) to guarantee satisfactory data reception were well below the lower boundary of C/N(o) of the communication link. Consequently, the feasibility of this technique was verified. PMID:8070809

Murakami, H; Shimizu, K; Yamamoto, K; Mikami, T; Hoshimiya, N; Kondo, K

1994-05-01

100

The satellite communications alternative for maritime safety  

Microsoft Academic Search

The current status of satellite communication technology for maritime users is surveyed, with an emphasis on emergency communication capabilities. Topics addressed include the organizational structure of Inmarsat, the present and planned Inmarsat space segment, the coastal and ship earth stations, the compact Standard-C terminal, the Enhanced Group Call system, and the L-band Satellite Emergency Position Indicating Radio Beacon. Consideration is

James L. Fear

1988-01-01

101

Federal Research and Development for Satellite Communications.  

ERIC Educational Resources Information Center

|This report of the Committee on Satellite Communications (COSC) reviews a number of future communication needs which could be satisfied by satellite systems, including needs in fields such as education, health care delivery, hazard warning, navigation aids, search and rescue, electronic mail delivery, time and frequency dissemination, and…

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

102

Future communication satellite systems and technology trends  

Microsoft Academic Search

Technological trends in communication satellite design and requirements were identified. The Intelsat program, TDR satellite systems, and the European large GEO platforms project were reviewed. There is a tendency towards modularized satellite buildup, large unfurlable lightweight multiple beam antennas 4 to 10 m for high frequencies (12 to 30 GHz) and up to larger than 100 m for lower frequencies,

H. Kellermeier; D. E. Koelle

1981-01-01

103

European small geostationary communications satellites  

NASA Astrophysics Data System (ADS)

Hispasat Advanced Generation 1 (HAG1) is the first satellite using the SGEO platform, which is under the development in the ESA Artes-11 program. Since the last presentation in the IAC 2007, a European industrial consortium led by OHB has completed the mission and spacecraft design. The platform Preliminary Design Review has been carried out in May 2008. The customer for the first mission is a commercial operator—Hispasat. The contract was signed in December 2008 and the satellite will be launched in 2012. To give confidence to the customer, SGEO platform will use up to date flight proven technologies. HAG1 carries 20/24 Ku-band and 3/5 Ka-band transponders to provide commercial services. Some innovative payload technologies will also be flown on board of HAG1 to gain in-orbit heritage. SGEO has also been selected as the baseline platform for the ESA Data Relay Satellite (EDRS). Phase-A study has just kicked off in January 2009. The targeted launch date is 2013. Heinrich Hertz will also use the SGEO platform. Heinrich Hertz is funded by the German Space Agency (DLR) and provides flight opportunities for technologies and components developed by the German Space Industry. With the HAG1 contract in hand, and EDRS and Heinrich Hertz in the line, OHB with its partners has the confidence that it will be able to speed up the product development of the SGEO platform for potential customers in the commercial market. This paper will first present the updated platform design and the status of the product development will be followed with the introduction of innovative payload technologies on board the first mission—HAG1 and ended with the mission concepts of EDRS and Heinrich Hertz missions.

Sun, Wei, , Dr.; Ellmers, Frank; Winkler, Andreas; Schuff, Herbert; Sansegundo Chamarro, Manuel Julián

2011-04-01

104

Soviet satellite communications science and technology  

NASA Astrophysics Data System (ADS)

The current state of the art and projections of future Soviet satellite communications technologies are discussed. A panel of six U.S. scientists and engineers 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 such as Japan, Italy, and France. 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 the published literature clearly shows that the Soviet Union has not exceeded 60 Mbps in its current space system. In response to decreased governmental support, the Soviet communications satellite industry is showing signs of some internal competition, is working on increasing communications satellite lifetime, and is also striving to develop joint ventures with Western firms.

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

1991-08-01

105

Communication satellite system beyond the year 2000  

NASA Astrophysics Data System (ADS)

The primary evolutionary factors of satellite communications technologies are reviewed based on the results of a study of novel satellite developments. A critical evaluation of the viability and availability of the technologies is utilized in conjunction with market forecasts to determine promising commercial strategies. Modern technologies are almost prepared for the development of a class of communications satellites and include bandwidth utilization, spacecraft bus modularity, and functional integration.

Robertson, G. J.; Fourquet, J. M.

1991-10-01

106

A new phase for NASA's communications satellite program  

NASA Astrophysics Data System (ADS)

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.

Dement, D. K.

1980-01-01

107

Broadcast satellite service: The international dimension  

NASA Astrophysics Data System (ADS)

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.

Samara, Noah

1991-09-01

108

Satellite communications in Europe - The earth-segment market  

NASA Astrophysics Data System (ADS)

The earth segment market of the new European satellite telecommunications field is projected for the next decade, and suggestions are made for its improvement. The home market for large Eutelsat stations (comprising the international telephone and television exchanges) is being dominated by the Japanese industry. Small station fixed satellite services (including business multiservices, distribution of CATV and SMATV, and the distribution of information to closed user groups) could create a substantial market for European industry with the relaxation of regulatory restraints. Four high-power satellites currently under development will open a market in direct broadcasting (DBS). Although the potential for mobile-satellite services (land mobile and maritime communications) is great, the European industry possesses only 15 percent of the present Inmarsat ship-terminal market. It is concluded that European industrial competitiveness could be increased by a general telecommunications policy for regulation, standardization, and research. Tables summarizing the telecommunications service potential and the satellite transponders available for TV distribution, are included.

Bartholome, P.; Hughes, C. D.

1985-11-01

109

Vibration noise control in laser satellite communication  

Microsoft Academic Search

Laser satellite communication has become especially attractive in recent years. Because the laser beam width is narrow than in the RF or microwave range, the transmitted optical power may be significantly reduced. This leads to development of miniature communication systems with extremely low power consumption. On the other hand, the laser communication channel is very sensitive to vibrations of the

Avigdor Saksonov; Shlomi Arnon; Norman S. Kopeika

2001-01-01

110

Study on the Applicability of Asynchronous Time Division (ATD) Techniques to Satellite Communications Systems.  

National Technical Information Service (NTIS)

Applicability of asynchronous transfer mode (ATM) in satellite communication systems of the fixed satellite service (FSS) was studied using two models: one model typical for a network, and another typical for a user oriented scenario. Equipment complexity...

H. Kuhlen G. Hertel M. Moerzinga A. Zambra M. Merri

1988-01-01

111

Giant step for communication satellite technology  

NASA Astrophysics Data System (ADS)

NASA's communications program, which is concerned with advanced communications technology, reflects the need for operational communications satellite capacity beyond the capabilities of current technology and the unwillingness of private industry in the U.S. to undertake making the required long-range, high-risk technology advances. It is pointed out that current satellites will not satisfy the forecasted demand for additional capacity in the 1990s and beyond. Current technology exists primarily up to 18 GHz. Designing a communications satellite at each of the three major uplink/downlink frequency bands (C, Ku, and Ka, 6/4 GHz, 14/11 GHz, and 30/20 GHz, respectively) presents different program management and technical problems. Increasing frequency or power can be done only by intensive sustained research. This is the rationale for NASA to pursue the Advanced Communications Technology Satellite (ACTS) program.

Lovell, R. R.

1984-03-01

112

Mobile satellite communications in the 1990's  

NASA Astrophysics Data System (ADS)

The evolution of Inmarsat global services from a single market and single service of the 1980's to all of the key mobile markets and a wide range of new terminals and services in the 1990's is described. An overview of existing mobile satellite services, as well as new services under implementation for introduction in the near and longer term, including a handheld satellite phone (Inmarsat-P), is provided. The initiative taken by Inmarsat in the integration of its global mobile satellite services with global navigation capability derived from GPS (Global Positioning System) and the GLONASS (Russian GPS) navigation satellite systems and the provision of an international civil overlay for GPS/GLONASS integrity and augmentation is highlighted. To complete the overview of the development of mobile satellite services in the 1990's, the known national and regional mobile satellite system plans and the various recent proposals for both orbiting and geostationary satellite systems for proving handheld satellite phone and/or data messaging services are described.

Singh, Jai

1992-07-01

113

Communication Satellites: Guidelines for a Strategic Plan.  

National Technical Information Service (NTIS)

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. Guid...

1987-01-01

114

The role of rain in satellite communications  

Microsoft Academic Search

The most fundamental obstacle encountered in design of satellite communication systems at frequencies above 10 GHz is attenuation by rain. The microwave power radiated toward an earth station, being limited by factors such as available primary power and size of antenna on the satellite, is insufficient, with present technology, to overcome the large attenuation produced by intense rain cells on

D. C. Hogg; Ta-Shing Chu

1975-01-01

115

Advanced antenna technologies for satellite communication payloads  

Microsoft Academic Search

This paper addresses some of the recent developments at LMCSS in the area of multiple beam and reconfigurable beam antennas for communication satellite payloads. These advancements include (a) multiple aperture dual-band reflector antennas, (b) high efficiency horns covering 50% bandwidth, (c) a novel ?stepped-reflector antenna? (SRA) technology, and (d) reconfigurable beam antennas for HIEO and GEO satellites. It is shown

Sudhakar Rao; Minh Tang; Chih-Chien Hsu; Jim Wang

2006-01-01

116

Operational disaster communications via satellite  

Microsoft Academic Search

Communications in disaster areas are often disrupted or so overburdened as to be of little value. Prompt restoration of reliable communications is needed to assess the extent of the damage and then to coordinate and distribute supplies to minimize the suffering. Therefore, reliable communications equipment, that can be transported easily, needs to be an integral part of the disaster assessment,

Neil R. Helm; David Wright

1992-01-01

117

Protected transitional solution to transformational satellite communications  

NASA Astrophysics Data System (ADS)

As the Warfighter progresses into the next generation battlefield, transformational communications become evident as an enabling technology. Satellite communications become even more vital as the battles range over greater non-contiguous spaces. While current satellite communications provide suitable beyond line-of-sight communications and the Transformational Communications Architecture (TCA) sets the stage for sound information exchange, a realizable transition must occur to ensure successful succession to this higher level. This paper addresses the need for a planned escalation to the next generation satellite communications architecture and offers near-term alternatives. Commercial satellite systems continue to enable the Warfighter to reach back to needed information resources, providing a large majority of available bandwidth. Four areas of concentration for transition include encrypted Telemetry, Tracking and Control (or Command) (TT&C), encrypted and covered data, satellite attack detection and protection, and operational mobility. Solution methodologies include directly embedding COMSEC devices in the satellites and terminals, and supplementing existing terminals with suitable equipment and software. Future satellites planned for near-term launches can be adapted to include commercial grade and higher-level secure equipment. Alternately, the expected use of programmable modems (Software Defined Radios (SDR)) enables incorporation of powerful cipher methods approaching military standards as well as waveforms suitable for on-the-move operation. Minimal equipment and software additions on the satellites can provide reasonable attack detection and protection methods in concert with the planned satellite usage. Network management suite modifications enable cohesive incorporation of these protection schemes. Such transitional ideas offer a smooth and planned transition as the TCA takes life.

Brand, Jerry C.

2005-06-01

118

Voice over IP service and performance in satellite networks  

Microsoft Academic Search

Voice over IP services have emerged as a low-cost alternative to PSTN voice service, and an attractive solution for voice\\/data integration in public and private networks. Satellite systems, as an integral part of the global communications infrastructure, already have an increasing portion of their capacities used to carry data packets, and with their global coverage and reach to remote areas

Thuan Nguyen; Ferit Yegenoglu; Agatino Sciuto; Ravi Subbarayan

2001-01-01

119

Revolutionary next generation satellite communications architectures and systems  

Microsoft Academic Search

This paper describes possible revolutionary next generation communications satellite missions and architectures. The satellite communications evolutionary background, current GSO's (geostationary orbit satellites), `Little', `Big' and `Broadband' NGSO's (non-GSO's), and enabling satellite technologies are briefly discussed. Converging technological and economic forces will drive us inevitably to the next decade's communication satellite systems and network architectures. The increasing pace of new capabilities,

J. R. Stuart; J. G. Stuart

1997-01-01

120

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

NASA Astrophysics Data System (ADS)

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.

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

1987-05-01

121

Land mobile communications satellite missions in Europe  

NASA Astrophysics Data System (ADS)

A market survey of the potential needs for land mobile communications in Europe in 1995 and 2005 was carried out. There is an exploding demand for land mobile communications in Europe. This demand justifies that every effort be made to develop as fast as possible a compatible pan-European terrestrial mobile system. The potential remaining needs, outside of the presently planned terrestrial mobile system, which can be served only by satellite, could exceed the capacity of a single medium size communications satellite in the available state of the art technology.

Deverdiere, R.

1986-09-01

122

Positioning determination and communications using two geostationary satellites  

NASA Astrophysics Data System (ADS)

A hybrid satellite communication system has been developed which can provide both communications and positioning services in one system using two geostationary satellites. The experimental system consists of the ETS-V (150 deg E) and INMARSAT (180 deg E), a base earth station (Kashima Space Research Center, Japan), and mobile earth stations. The frequencies between the satellites and mobile stations are 1.6/1.5 GHz. The distinctive feature of this system is that position determination of the mobile earth stations and communication, such as voice and data transmission, can be carried out over the same channel at the same time. Another feature is that the frequency bandwidth of the system is very narrow compared to those of GPS and GEOSTAR. The two types of terminals developed for the experiments with this hybrid system use the single channel per carrier method and the spread spectrum method. An outline of the experimental system is presented, and the estimated positioning accuracy is described.

Morikawa, Eihisa; Miura, Ryu; Kimura, Kazuhiro; Kawase, Seiichiro; Ohmori, Shingo; Matsumoto, Yasushi; Wakao, Masayoshi

1992-07-01

123

Satellite delivery of B-ISDN services  

NASA Astrophysics Data System (ADS)

This paper will address the role of technology in the satellite delivery of B-ISDN services. Satellites excel in serving remote users and in providing multicast and broadcast services. Benefits to potential users employing these satellite broadband services will be examined together with their respective network architecture. Two application requirements are then proposed. The critical technologies needed in the realization of these architectures will be identified.

Kwan, R. K.; Price, K. M.; Chitre, D. M.; White, L. W.; Henderson, T. R.

1992-03-01

124

European small geostationary communications satellites  

Microsoft Academic Search

Hispasat Advanced Generation 1 (HAG1) is the first satellite using the SGEO platform, which is under the development in the ESA Artes-11 program. Since the last presentation in the IAC 2007, a European industrial consortium led by OHB has completed the mission and spacecraft design. The platform Preliminary Design Review has been carried out in May 2008. The customer for

Wei Sun; Frank Ellmers; Andreas Winkler; Herbert Schuff; Manuel Julián Sansegundo Chamarro

2011-01-01

125

The history and future of commercial satellite communications  

NASA Astrophysics Data System (ADS)

The development and operations of commercial satellite communications are described. The development of passive satellites and early active satellites is reviewed, a list of operational and planned communications satellite systems is presented, and active satellites are discussed, including global fixed civil telecommunications satellites, regional systems, domestic fixed satellite systems, global mobile systems, domestic mobile and broadcast systems, and experimental satellites. Comparisons with other transmission techniques are made, the use of earth stations is briefly examined, and industrial growth and future trends are considered.

Pritchard, W. L.

1984-05-01

126

Satellite services for disaster management and security applications  

NASA Astrophysics Data System (ADS)

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.

Koudelka, Otto; Schrotter, P.

2007-06-01

127

Telematic services via satellite in Europe  

Microsoft Academic Search

Telematics in Europe is intended to provide service through five satellites: Eutelsat, Telecom 1, Unisat, DFS, and Italsat. A 'Central Europe' zone will have coverage from the five satellites simultaneously; Eutelsat will be at the hub of the network and will have the largest coverage of all. Two to five transponders per satellite are to be used for telematic special

C. Goumy; E. Golden

1984-01-01

128

Von Karman Lecture - The rocky road to communication satellites  

NASA Astrophysics Data System (ADS)

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.

Wheelon, A. D.

1986-01-01

129

GLOBAL MOBILE SATELLITE COMMUNICATIONS: A REVIEW OF THREE CONTENDERS  

Microsoft Academic Search

The era of satellite-based mobile communications systems started with the first MARISAT satellite which was launched into a geostationary orbit over the Pacific Ocean in 1976 to provide communications between ships and shore stations. The combination of high cost and unacceptably large equipment has kept mobile satellite communications (MSC) systems from appealing to the wider market of personal mobile communications.

Gary M. Comparetto

1994-01-01

130

Securing multimedia services over satellite ATM networks  

Microsoft Academic Search

1. SUMMARY In recent years, there has been increasing interest in interconnecting satellite and ATM networks because both share common characteristics of the ability to provide bandwidth-on-demand and flexibility of integrating voice, video and data services. There are several new satellite constellation proposals that support multimedia service and transport ATM traffic. For a successful implementation of such systems, it is

H. Cruickshank; I. Mertzanis; B. G. Evans; H. Leitold; R. Posch

1998-01-01

131

Satellite Antenna Pointing Procedure Driven by the Ground Service Quality  

NASA Astrophysics Data System (ADS)

A satellite antenna alignment technique is proposed to ensure terrestrial service quality for users. The antenna bore sight orientation is calculated directly from measured data acquired from general ground receivers, which intercept the communication radio waves from any position on the earth's surface. The method coordinates the satellite pointing parameters with signal strength at the receivers while considering location-specific geographical and antenna radiation characteristics and control accuracy. The theoretical development and its validity are examined in the course of equation derivation. Actual measured data of an existing satellite at the maneuver was applied to the method, and the capability was demonstrated and verified. With the wide diversity of satellite usage, such as for mobile communications, temporary network deployment or post-launch positioning accommodations, the proposed method provides a direct evaluation of satellite communication performance at the service level, in conjunction with using high frequency spot beam antennas, which are highly susceptible to pointing gain. This can facilitate swift and flexible satellite service planning and deployment for operators.

Yasui, Yoshitsugu

132

The future role of satellite communications in an improved air traffic management  

NASA Astrophysics Data System (ADS)

The need for air to ground communication in Air Traffic Control (ATC) is discussed and a summary on the birth of aeronautical satellite communication is given. The standardization of an aeronautical mobile communications service by the International Civil Aviation Organization is reported. The feasibility analysis of satellite communications for ATC carried out by the French civil aviation is described. This 'South Pacific Trial' is regarded as a first step towards a full operational implementation.

Gauthier, Patrice

1992-07-01

133

Shuttle impact on commercial communications satellites  

Microsoft Academic Search

The shuttle brings new freedom and challenge to spacecraft designers. Commercial communications satellites, one of the shuttle's largest customer classes, are adapting to its use. This paper presents background from the user's point of view, with the Intelsat program as a case in point. It discusses the immediate impact of the shuttle on Intelsat V and considers spacecraft optimized for

F. H. Esch; C. J. Pentlicki

1977-01-01

134

Distributed Source Coding for Satellite Communications  

Microsoft Academic Search

Inspired by mobile satellite communications systems, we consider a source coding system which consists of multiple sources, multiple encoders, and multiple decoders. Each encoder has access to a certain subset of the sources, each decoder has access to certain subset of the encoders, and each decoder reconstructs a certain subset of the sources almost perfectly. The connectivity between the sources

Raymond W. Yeung; Zhen Zhang

1999-01-01

135

Viterbi Decoding for Satellite and Space Communication  

Microsoft Academic Search

Convolutional coding and Viterbi decoding, along with binary phase-shift keyed modulation, is presented as an efficient system for reliable communication on power limited satellite and space channels. Performance results, obtained theoretically and through computer simulation, are given for optimum short constraint length codes for a range of code constraint lengths and code rates. System efficiency is compared for hard receiver

J. Heller; I. Jacobs

1971-01-01

136

Laser satellite communications: current status and directions  

Microsoft Academic Search

This summary paper outlines the advantages of laser satellite communications (laser satcom) and summarizes the status of relevant programs. It concludes that laser satcom systems offer valuable performance capabilities and system advantages. It notes the urgent need for flight demonstrations to establish the viability and characterize the performance of laser satcom systems.

Geoffrey Hyde; Burton I. Edelson

1997-01-01

137

Satellite communications representation in network simulation  

Microsoft Academic Search

This paper presents methodologies to represent satellite communications (SATCOM) behaviors in network simulation. This paper is based on tasks performed for generic network warfare simulation that employs traditional network simulation models. The methodologies also include the integration issues of SATCOM tools and the network simulation models. We first characterize space segments and assets involved in warfare operations and exercises, and

Kenneth Y. Jo

2001-01-01

138

Satellite communications: Passage to middle age?  

Microsoft Academic Search

The commercial satellite communications industry is barely more than two decades old and is already experiencing symptoms of passage to middle age: The regulated environment of its early youth protected its market share and promoted investment in space and earth facilities designed to maximize transmission capacity for international point to point telephone traffic among a relatively few expensive earth antennas.

D. DiFonzo

1986-01-01

139

Assessment of Commercial Satellite Communications Initiative (CSCI) studies  

NASA Astrophysics Data System (ADS)

This report summarizes the fixed and mobile satellite services (FSS, MSS) as studied by three contractors: COMSAT, Hughes, and Space Systems/LORAL. Each contractor developed a commercial satellite communications initiative (CSCI) architecture based on the requirements provided them from DOD's Integrated Communications Data Base (ICDB). An implementation plan, recommending an acquisition, transition, logistics, and host nation approval plan, was developed according to each contractor's recommended architecture. In addition, this report summarizes the demonstrations conducted by each contractor and the vulnerabilities inherent in using commercial satellites. This summary information is provided as the foundation for the section on the government's assessment and critique of the CSCI study which emphasizes the highlights and remaining uncertainties from this program.

Smith, N.; Kearns, W.; Chapell, P.

1994-01-01

140

Satellite mobile data service for Canada  

NASA Astrophysics Data System (ADS)

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.

Egan, Glenn R.; Sward, David J.

141

Geostationary communications satellite orbit utilization strategies for the 1980s  

NASA Astrophysics Data System (ADS)

Orbital congestion became apparent when the number of applications filed with the Federal Communication Commission (FCC) for 6/4 GHz orbital slots exceeded the number of slots available. In order to overcome this congestion, approaches must be studied for increasing the capacity of the geostationary orbit. In connection with an identification of the factors which affect geostationary orbit capacity, three types of capacity are introduced, including site capacity, service area capacity, and total capacity of the geostationary orbit. Attention is given to approaches for increasing the number of satellites in the geostationary orbit, the phased introduction of new technology, increased interference allocations from other satellites, methods for increasing the spectral efficiency by channel equipment design, the possibility to increase the spectral efficiency by antenna design and frequency reuse, procedures for increasing the available bandwidth, and the development of techniques for optimizing the placement of satellites serving different service areas.

Hedinger, R. A.

142

A network architecture for International Business Satellite communications  

NASA Astrophysics Data System (ADS)

Demand Assignment (DA) control is expected to be introduced in the International Business Satellte communications (IBS) network in order to cope with a growing international business traffic. The paper discusses the DA/IBS network from the viewpoints of network configuration, satellite channel configuration and DA control. The network configuration proposed here consists of one Central Station with network management function and several Network Coordination Stations with user management function. A satellite channel configuration is also presented along with a tradeoff study on transmission bit rate, high power amplifier output power requirement, and service quality. The DA control flow and protocol based on CCITT Signalling System No. 7 are also proposed.

Takahata, Fumio; Nohara, Mitsuo; Takeuchi, Yoshio

143

Commercial communications satellite market and technology in the 90's  

NASA Astrophysics Data System (ADS)

A description is presented of a user requirement study which was conducted during the fall of 1982 to determine possible commercial communications missions for a low-earth orbit space station under consideration for the 1990s. The study included a review of the literature on large space structures for communications. The survey returns were grouped into four categories, taking into account missions relating to testing, space communications technology, scientific research priorities and suggestions for cost savings in space, and communications traffic growth. In discussions regarding the space station, of considerable interest to many of the participants was the concept of the space station as a "service station-in-the-sky". Some interest was expressed in a low-earth orbit communications satellite.

Filep, R. T.

1983-10-01

144

Communication Systems through Artificial Earth Satellites (Selected Pages).  

National Technical Information Service (NTIS)

Contents: Principles of the Construction of Communication Systems Through Artificial Earth Satellites; Motion of Satellites and Duration of Periods of Communication; Signal Level at the Input of Receiver; Noise Level at the Input of a Receiver; Calculatio...

N. I. Kalashnikov

1987-01-01

145

New trends in laser satellite communications: design and limitations  

Microsoft Academic Search

Optical communications offer a capable alternative to radio frequency (RF) communications for applications where high data-rate is required. This technology is particularly promising and challenging in the field of future inter-satellite communications. The term laser satellite communications (LSC) stands for optical links between satellites and\\/or high altitude platforms (HAPs). However, optical links between an earth station and a satellite or

J. Císar; O. Wilfert; F. Fanjul-Vélez; N. Ortega-Quijano; J. L. Arce-Diego

2008-01-01

146

Design on an enhanced interactive satellite communications system analysis program  

Microsoft Academic Search

This thesis describes the design of a user-friendly interactive satellite communications analysis program for use on a personal computer. The user inputs the various parameters of a satellite orbit, ground station location and communications equipment. The output generated allows a user to view the satellite ground trace and footprint, calculate satellite rise and set times, and analyze the performance of

Kevin Robert Andersen

1991-01-01

147

Plan of Advanced Satellite Communications Experiment Using ETS-VI (Engineering Test Satellite VI).  

National Technical Information Service (NTIS)

Communications Research Laboratory (CRL, Ministry of Posts and Telecommunications, Japan) has been engaged in development of three advanced satellite communication payloads aiming at experiments by Japan's 2-ton class Engineering Test Satellite VI (ETS-VI...

T. Shiomi

1988-01-01

148

Future Satellite Navigation Services and Augmentations.  

National Technical Information Service (NTIS)

This report is intended to provide a high-level view of the evolving changes in satellite navigation services. Satellite navigation dates back as one of the first space applications. The report provides a chronological review of the development of the Glo...

J. W. Spalding

2006-01-01

149

Satellite Mobile Data Service for Canada.  

National Technical Information Service (NTIS)

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 test...

G. R. Egan D. J. Sward

1990-01-01

150

Engineering calculations for communications satellite systems planning  

NASA Astrophysics Data System (ADS)

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.

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

1983-12-01

151

Land mobile communications satellite mission (LAMOCOSAMIS) Task 1: Market study  

NASA Astrophysics Data System (ADS)

Land mobile communication service demand in Europe and the Mediterranean basin in the years 1995-2005 was estimated. A traffic model was derived. There is an exploding demand for land mobile communications in Europe, with overwhelming preference for two way telephone services. The users survey shows a surprising lack of sensitivity to prices and tariffs, which widely contributed to the preeminence of the needs for telephone services. This demand justifies that every effort be made to develop as fast as possible a compatible pan-European terrestrial mobile system. If a large proportion of the needs may be satisfied by terrestrial mobile system solutions, the potential remaining needs for telephony, outside of the presently planned terrestrial mobile, which can be served only by satellite, even under the pessimistic economic scenario and high cost/tariff assumptions, requires a number of equivalent telephone circuits which cannot be achieved with available state of the art technology.

1985-12-01

152

Advancing the art of satellite communications - Foreign competition spurs NASA Satcom research  

Microsoft Academic Search

Major advances in satellite communications technology in the US and Japan are detailed. Japan's Ka-band services aboard CS-2a and CS-2b, launched in 1973, are discussed, as well as plans for the ECS-2 and ACTS-E (Advanced Communications Technology Satellite) experimental projects. The ACTS-E would carry both a broadcasting payload operating at 27\\/22 GHz and a communication payload using the 50\\/40 GHz

C. Bulloch

1985-01-01

153

Development of a demand assignment/TDMA system for international business satellite communications  

NASA Astrophysics Data System (ADS)

An experimental IBS (international business satellite) communications system based on a demand assignment and TDMA (time-division multiple-access) operation has been developed. The system utilizes a limited satellite resource efficiently and provides various kinds of ISDN services totally. A discussion is presented of the IBS network configurations suitable to international communications and describes the developed communications system from the viewpoint of the hardware and software implementation. The performance in terms of the transmission quality and call processing is also demonstrated.

Nohara, Mitsuo; Takeuchi, Yoshio; Takahata, Fumio; Hirata, Yasuo; Yamazaki, Yoshiharu

154

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

...COMMUNICATIONS COMMISSION (CONTINUED) COMMON CARRIER SERVICES SATELLITE COMMUNICATIONS...affidavit of a person or persons with knowledge thereof) to demonstrate that the milestone...affidavit of a person or persons with knowledge thereof) to demonstrate that the...

2011-10-01

155

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

...COMMUNICATIONS COMMISSION (CONTINUED) COMMON CARRIER SERVICES SATELLITE COMMUNICATIONS...affidavit of a person or persons with knowledge thereof) to demonstrate that the milestone...affidavit of a person or persons with knowledge thereof) to demonstrate that the...

2012-10-01

156

Leveraging Commercial Communication Satellites to support the Space Situational  

NASA Astrophysics Data System (ADS)

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.

Deaver, T.

157

Project SCS (Special Communication Services).  

National Technical Information Service (NTIS)

This extensive report describes and provides documentation on Special Communications Services for the Sensory Impaired (SCS), a Virginia-based telecommunications delivery system developed by the Center for Excellence, Inc. (CenTex), to provide information...

J. A. Curtis

1982-01-01

158

Network design consideration of a satellite-based mobile communications system  

NASA Astrophysics Data System (ADS)

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.

Yan, T.-Y.

159

The communication-satellite market to the year 2000  

NASA Astrophysics Data System (ADS)

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.

van Duinen, R. J.

1984-10-01

160

Maritime safety communication experiments with the ATS6 satellite  

Microsoft Academic Search

Maritime and aeronautical satellite communications experiments were conducted using the NASA Applications Technology Satellite-Number 6 (ATS-6) from September 1974 through April 1975. The ATS-6 satellite maritime experiments have produced data useful for preparing specifications of ship terminals for possible future operational satellite systems. Evaluations were performed of a shipboard antenna design, various types of voice, data, and ranging modulations, and

J. M. Gutwein; J. A. Wolfson; P. D. Engles

1975-01-01

161

Denial of service prevention in satellite networks  

Microsoft Academic Search

Networks integrating satellite shared access, such as DVB-S\\/RCS, are particularly exposed to denial of service (DoS) attacks through which a satellite terminal can maliciously use the Network Control Center (NCC) resources by submitting a high number of bogus requests. Anti-clogging techniques used in terrestrial mesh networks to thwart DoS attacks fall short of solving DoS problems in the case of

M. Onen; R. Molva

2004-01-01

162

An experimental study of electrical characteristics of mesh reflecting surface for communication satellite antenna  

Microsoft Academic Search

While mesh material is often used for the reflecting surface of satellite antennas because it is lightweight and elastic due to its stitched structure, little research and development have been done for the mesh reflecting surface used for the satellite antenna using the frequency such as the Ka-band. A large deployable antenna with 7-m diameter, which provides communications service in

A. Miura; M. Tanaka

2003-01-01

163

Study of LEO-SAT Microwave Link for Broad-Band Mobile Satellite Communication System.  

National Technical Information Service (NTIS)

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 degr...

M. Fujise W. Chujo I. Chiba Y. Furuhama K. Kawabata

1993-01-01

164

Telematic services via satellite in Europe  

NASA Astrophysics Data System (ADS)

Telematics in Europe is intended to provide service through five satellites: Eutelsat, Telecom 1, Unisat, DFS, and Italsat. A 'Central Europe' zone will have coverage from the five satellites simultaneously; Eutelsat will be at the hub of the network and will have the largest coverage of all. Two to five transponders per satellite are to be used for telematic special services on the 12.5-12.75 GHz down-link band; Italsat will use a 20 GHz down-link. The ground segment will use several hundred small 3.5 m dish antennas and SCPC or 25-60 Mb/s TDMA equipment. Among many services, telematics will include videoconferences, computer-to-computer data transfer, high speed facsimile, and transatlantic digital business. Although all five networks will operate independently, future interconnection among them will allow efficiency improvements.

Goumy, C.; Golden, E.

1984-03-01

165

First Satellite Mobile Communication Trials Using BLQS-CDMA.  

National Technical Information Service (NTIS)

In this paper, technical results obtained in the first MSBN Land mobile technical trial are reported. MSBN (Mobile Satellite Business Network) is a new program undertaken by the European Space Agency (ESA) to promote mobile satellite communication in Euro...

M. Luzdemateo S. Johns M. Dothey C. Vanhimbeeck I. Deman

1993-01-01

166

Prospects of satellite communications for mobiles: Towards a global mobile space segment  

NASA Astrophysics Data System (ADS)

Terrestrial, maritime, and air transportation applications of communications satellites are considered. Communicating with long distance trucks can be achieved by text transmission which is cheaper than voice links, avoids access problems, and uses the frequency spectrum more efficiently. The need to accept fast and slow air traffic in the same air space, especially near airports, creates safety problems that can be overcome by equipping aircraft with a satellite controlled display device, showing traffic in the vicinity. The maritime satellite service is characterized by low market penetration that can be improved by cutting equipment costs, e.g., by decreasing ship antenna performance and using high gain satellite antennas, producing narrow beams.

Rosetti, C.

1981-11-01

167

Ka-band aeronautical satellite communications experiments using COMETS  

Microsoft Academic Search

This paper describes the results of evaluation tests of an aeronautical satellite communications experiments system in the Ka-band using Japan's communications and broadcasting engineering test satellite (COMETS). An active phased-array antenna with an open-loop satellite tracking capability operating in the Ka-band was installed just behind the passenger window of an airplane to receive a satellite signal. The propagation measurements showed

Amane Miura; Shinichi Yamamoto; Huan-Bang Li; Masato Tanaka; Hiromitsu Wakana

2002-01-01

168

Land mobile communications and position fixing using satellites  

Microsoft Academic Search

Relay of land mobile communications directly between the vehicles and central stations using VHF repeaters on satellites in geosynchronous orbits is examined. Experiments demonstrated effective satellite-aided land mobile communications, analog and digital data relay, automatic real-time vehicle position fixing; specially designed satellite antenna, and a digital tone-code ranging responder which operates within the communications bandwidth. A commercial VHF base station

A. F. Brisken; R. E. Anderson; R. L. Frey; J. R. Lewis

1979-01-01

169

Development of aeronautical mobile satellite services over the past thirty years  

NASA Astrophysics Data System (ADS)

This paper presents an overview of the development of aeronautical mobile satellite services (AMSS) over the past 30 years. The inherent shortcomings of present air-ground HF communications have hindered the development of civil aviation, but according to the Future Air Navigation Systems (FANS) concept aeronautical satellite communication - including Automatic Dependent Surveillance (ADS) - will be the key to eliminating the shortcomings of HF communication systems. Satellite-based communication and surveillance will significantly improve air traffic control (ATC) over the oceanic and remote terrestrial airspace, and it will benefit civil aviation authorities, airlines as well as passengers. This paper discusses the availability of system elements, and world wide trials, demonstrations and preoperational use of aeronautical satellite communications over past years are described. Future satellite systems possible for aeronautical communications are also discussed.

Chen, Guangren; Xiong, Fuqin

1994-12-01

170

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

NASA Astrophysics Data System (ADS)

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.

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

171

EUTELTRACS: The European land mobile satellite service  

NASA Astrophysics Data System (ADS)

EUTELTRACS is Europe's first commercially operated land mobile satellite service. EUTELTRACS provides an integrated message exchange and position reporting service for the European transportation industry with the aim of increasing cost effectiveness, radically improving efficiency and security and enhancing business flexibility. The architecture of the system is described, outlining the accuracy of the position determination, and an overview of the commercial deployment of EUTELTRACS is given.

Colcy, Jean-Noel; Steinhaeuser, Rafael; Mock, Kimberly

1992-07-01

172

17/12 GHz communication receiver for direct broadcast satellites  

NASA Astrophysics Data System (ADS)

The Direct Broadcast Satellite (DBS) Service represents a new arena for the development and application of spacecraft technologies. The new satellites will employ high radiated power carrier levels to provide TV signals directly to private homes and businesses. The high carrier levels will make it possible to employ inexpensive receivers and small antennas suitable for home installation. A description is given of the 17/12 GHz communication receiver for the first high-power U.S. DBS, which is to be launched in 1986. The receiver utilizes a compact and all-solid-state design. The three subassemblies of the receiver include the RF (or microwave) unit, the local oscillator unit, and the DC/DC converter unit. The receiver offers excellent transmission characteristics and stable performance in its operating environment.

Dhillon, S. S.; Goldgeier, P.; Sudarsanam, R.; Goldberg, H.

1984-10-01

173

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

Code of Federal Regulations, 2011 CFR

...Telecommunication FEDERAL COMMUNICATIONS COMMISSION (CONTINUED) COMMON CARRIER SERVICES SATELLITE COMMUNICATIONS Applications...information (supported by affidavit of a person or person with knowledge thereof) to demonstrate that the milestone has been...

2011-10-01

174

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

Code of Federal Regulations, 2012 CFR

...Telecommunication FEDERAL COMMUNICATIONS COMMISSION (CONTINUED) COMMON CARRIER SERVICES SATELLITE COMMUNICATIONS Applications...information (supported by affidavit of a person or person with knowledge thereof) to demonstrate that the milestone has been...

2012-10-01

175

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

NASA Astrophysics Data System (ADS)

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.

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

1988-05-01

176

Direct broadcast satellite service by direct broadcast satellite corporation  

NASA Astrophysics Data System (ADS)

It is noted that common carrier operation implies the offer to transmit television programs or any other information in electronic form for any customer at a rate posted in a tariff recorded at the FCC and applied without discrimination. The satellite system developed must be flexible enough to provide virtually any transmision service its customers may decide to offer at some future time. This means that spot beams must be available, which will permit the programmer to concentrate his offerings on particular regions of the country. Also, with the first satellite, there will be full-coverage service to the entire contiguous United States; in this way, programmers wishing to reach a nationwide audience will be able to do so from the beginning of their DBS operation. In addition, there will be an effective isotropic radiated power level that is high enough to accommodate high-definition television. As a common carrier, it is also necessary to seek the maximum possible standardization of signal transmission formats, receiver and antenna characteristics, and satellite locations so that programmers wishing to provide either subscription-supported or advertiser-supported programs can reach the widest possible audiences.

Pritchard, W. L.; Radin, H. W.

1984-03-01

177

Demonstration of a Ka-Band communication path for On-Orbit Servicing  

Microsoft Academic Search

The objectives of on-orbit servicing (OOS) missions include manipulation, proximity operations and inspection of target satellites. Therefore the servicer satellite often has to be teleoperated at low latency for several minutes to fulfill these tasks. That means communication plays a crucial role for OOS missions because real time teleoperation including high data rates has to be realized. So the communication

R. Purschke; J. Harder; A. Fleischner

2011-01-01

178

Engineering management consideration for an integrated aeronautical mobile satellite service  

NASA Astrophysics Data System (ADS)

In order to meet local air traffic control terminal requirements as well as national and transborder requirements, countries have developed communications, navigation, and surveillance (CNS) systems having little systems integration and a solely ground-based solution to air traffic control problems. It is believed that the application of satellite technology is the only currently viable solution that will enable international civil aviation to overcome the shortcomings of the presently available CNS systems. If properly implemented, available satellite system technology integrated with avionics and ground based capabilities, can be used to meet new global aviation demands. A clear transition plan has to be implemented so as to ensure continuity of service, recognize user-borne costs, and satisfy institutional and national objectives in the progress toward a universal air traffic management (ATM) system. ATM systems design should rely on a modular approach for flexibility and upgrading. An aeronautical mobile satellite service is intended to provide a worldwide satellite data link and direct air/ground voice communication. Institutional and financial roadblocks for implemetation of a global based approach will likely be far greater than technical constraints.

Belcher, John M.

179

6 Channel PCM Sound Receiver For Japanese Communication Satellite Audio Broadcasting System  

Microsoft Academic Search

The 6 channel PCM sound receiver for Japanese Chi- - nUitlPiLXer -6 CS(Communication Satellite) audio broadcasting PCI High-quality PCM sound broadcasting service via CS in the 12 GHz band will be started soon in Japan. In this service, 6 channels of 2.048Mbps PCM sound signal are multiplexed by time division, and are broadcasted to home individually using one satellite transponder(l).

Tomozo OHTA; Masao MIYAZAKI; Takamitsu KITAYAMA; Takahiro CHIHARA; Minoru KUBOTA; Yasuhiro HAMAGUCHI; Kazuhiro KISHIMOTO

1992-01-01

180

DOC's role in the development of social service satellite delivery systems  

NASA Astrophysics Data System (ADS)

Over the past decade, the Department of Communications (DOC) has been actively involved in fostering the development of telecommunications services for the benefit of the people of Canada through the Hermes and ANIK-B satellite programs. Hermes, an experimental satellite, had been designed to test new spacecraft technology and to function in the 14/12 GHz band. The satellite was developed under a joint program with U.S. NASA. The satellite was launched in January 1976, and performed satisfactorily until late 1979. ANIK-B, primarily a 6/4 GHz satellite for carrying regular Canadian domestic satellite services, was launched in December 1978. Four 14/12 GHz transponders on ANIK-B were leased by DOC to continue programs initiated on Hermes. These programs included service development projects related to broadcasting, education, health-care community communications, and administration.

Jelly, D. H.

181

Customer Service/Telephone Communications.  

ERIC Educational Resources Information Center

This document is the facilitator's edition of a curriculum designed to be presented as a four-session workshop for customer service and credit department employees of a manufacturing company. It was developed by educators from the Emily Griffith Opportunity School. The workshop is designed around a basic communication model incorporating the three…

Fletcher, Karen

182

Technical comparison of several global mobile satellite communications systems  

NASA Astrophysics Data System (ADS)

The era of satellite-based mobile satellite communications (MSC) systems started with the first MARISAT satellite which was launched into a geostationary orbit over the Pacific Ocean in 1976 to provide communications between ships and shore stations. The combination of high cost and unacceptably large equipment has kept the space-based MSC systems from appealing to the wider market of personal mobile communications. The progress made over the last ten years, however, in digital voice processing, satellite technology, and component miniaturization has resulted in the viability of satellite-based mobile satellite communications systems to meet the growing market in personal mobile communications using handsets similar to those currently in use with land-based cellular systems. Three of the more mature LEO/MEO satellite systems are addressed in this paper including GLOBALSTAR, Iridium, and Odyssey. The system architectures of each system are presented along with a description of the satellite and user handset designs and the multiaccess techniques employed. It will be shown that, although a number of similarities exist among the system addressed, each system is unique in a variety of significant design areas. It is concluded that the technical feasibility of satellite-based mobile satellite communications systems seems to be secure. It will be challenging, however, for the vendors to actually develop and deploy these systems in a cost effective, timely, and reliable way that meets a continually evolving set of requirements based upon a rapidly changing technology base.

Comparetto, Gary M.

183

The Automated Digital Network System (ADNS) Interface to Transformational Satellite Communications System (TSAT)  

Microsoft Academic Search

The U. S. Department of Defense (DoD) is in the initial phase of building the Global Information Grid (GIG), a private secure internetwork connecting a number of its joint and service-specific IP networks. Two of these networks are the Automated Digital Network System (ADNS) and the Transformational Satellite Communications System (TSAT). ADNS provides network services and entry into the Defense

Joanna N. Ptasinski; Yenchi Congtang

2007-01-01

184

The role of technology in influencing future civil communications satellites  

Microsoft Academic Search

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

JAMES W. BAGWELL; CHRISTOPH E. MAHLE

1990-01-01

185

Satellite broadcasting and communications in the Asia-Pacific region  

NASA Astrophysics Data System (ADS)

Against the general context of worldwide developments in satellite communications and broadcasting, and the recent ORB'85 Conference, this paper assesses the future for satellite communication and broadcasting in the Asia-Pacific region. While most attention focusses on satellite developments for the industrialized world, the Asia-Pacific region is expected to play an increasingly significant role, and the needs of its population will be satisfied by development of satellite communications and broadcasting systems. Particular emphasis is placed in this paper on the broadcasting aspects, and their relationship to cultural and economic development.

Bonzon, S.

1985-12-01

186

Man-Made Moons: Satellite Communications for Schools.  

ERIC Educational Resources Information Center

|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…

Grayson, Lawrence P.; And Others

187

A Hierarchy Management Framework for LEO Satellite Communication Networks  

Microsoft Academic Search

An autonomous iteration-based approach is proposed to identify faulty links for LEO satellite systems employing intersatellite links (ISLpsilas). A designed network satellite with management responsibilities collects the routing information of communication itself with other satellites, based on which a fault diagnosis model is introduced. Then the most likely faulty link is identified by using an iteration-based probability method, in conjunction

Zhi-Gang Zhao; Jian-Hui Wang

2008-01-01

188

An advanced conceptual design study for a mobile satellite communications system  

NASA Astrophysics Data System (ADS)

It is pointed out that a vast portion of the land mass, and a significant portion of the U.S. population in rural and remote areas, are deprived of most of the advanced telecommunication services offered in metropolitan areas. For the last decade, investigations have been conducted regarding the feasibility to provide telecommunication services throughtout the thinly populated areas with the aid of a geostationary satellite. The considered communication services are related to mobile and thin-route radiotelephony, wideband and narrowband data transmissions, and position location services. The mobile satellite (MSAT) communications system studied could provide a truly national and ubiquitous service. Attention is given to satellite antenna design, an MSAT link design analysis, and analysis results.

Salmasi, A. B.

189

Role of satellite communication in transport objects management  

NASA Astrophysics Data System (ADS)

A prerequisite for proper operation of a system for managing transport vehicles is the availability of a reliable communications medium for data exchange between the mobile element and the management center. Here, the role of satellite communication in such a system is addressed. A ship automatic control system which serves as an information provider to a centralized traffic management system is described, and the selection of suitable satellite channels is discussed. A system for satellite-aided search and rescue is examined.

Lavkovskii, V.; Cherniaev, R.; Volodin, V.

1990-10-01

190

Japanese first optical interorbit communications engineering satellite (OICETS)  

NASA Astrophysics Data System (ADS)

The National Space Development Agency of Japan (NASDA) plans to conduct an optical inter-orbit ling experiment in cooperation with the European Space Agency (ESA). ESA will launch the ARTEMIS geostationary satellite equipped with the SILEX optical terminal. NASDA will launch the Optical Inter-orbit Communications Engineering Test Satellite (OICETS) equipped with the LUCE optical inter-orbit communications equipment into low earth orbit. The link experiment will be conducted between these satellites with associated ground equipment in Europe and Japan.

Yamamoto, Akio; Hori, Toshihiro; Shimizu, Takafumi; Nakagawa, Keizo

1994-09-01

191

Controlling satellite communication system unwanted emissions in congested RF spectrum  

NASA Astrophysics Data System (ADS)

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

Olsen, Donald; Heymann, Roger

2007-09-01

192

Performance of a global circuit-switched satellite communication network  

Microsoft Academic Search

A circuit-switched network consisting of multiple low Earth orbiting satellites and three geostationary satellites is considered. Crosslinks among low-orbit satellites are used as the major communication channels, while calls are routed via geostationary satellites only when low-orbit routes exceed or equal to a hop-count threshold. Simulation results are used to illustrate the network throughput under various traffic conditions and different

Zsehong Tsai; Chuan-Chen Chuang; Jin-Fu Chang; Chun-Ming Huang

1994-01-01

193

Reconsidering Social Networks for Enterprise Communication Services  

Microsoft Academic Search

Social networking applications leverage valuable information from social graphs and integrate communication capabilities to offer new services. However, currently, these applications are limited to communication capabilities such as click-to-call or click-to-conference. Once the communication session is established the social context and the communication context are not integrated in these services. For social network communication services such integration permits new and

Krishna Kishore Dhara; Venkatesh Krishnaswamy; Taranjeet Singh

2010-01-01

194

Study of the Communications Services Industrial Fund.  

National Technical Information Service (NTIS)

The Communications Services Industrial Fund (CSIF) is an integral tool available to the Defense Communications Agency in directing and controlling the operations of the Defense Communications System. This thesis is an analysis of how effective the current...

J. M. Hinton

1985-01-01

195

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

Federal Register 2010, 2011, 2012, 2013

...Pan-Pacific Education and Communications Experiments by Satellite (PEACESAT): Closing...Pan-Pacific Education and Communications Experiments by Satellite (PEACESAT) Program...Pan-Pacific Education and Communications Experiments by Satellite (PEACESAT) Program...

2010-03-18

196

Communication as an element of service value  

Microsoft Academic Search

Purpose – The paper explores consumers' responsiveness to marketing communication about various services and products in three different media. Communication value is seen as an element of service value and is measured as consumer responsiveness to marketing communication. Design\\/methodology\\/approach – The empirical data is based on interviews with consumers concerning their perceptions of the relevance and acceptance of marketing communication

Kristina Heinonen; Tore Strandvik

2005-01-01

197

Emerging commercial opportunities based on combined communication navigation services  

NASA Astrophysics Data System (ADS)

Cost reduction pressure on companies and increasing regulatory and legislative demand together with rapid technological progress in space-based communication and navigation are opening up new and exciting commercial opportunities. In this framework, a novel service for maritime applications is presented using a two-way messaging system and the global navigation satellite system (GNSS). The system implements an end-to-end solution for asset tracking and fleet management, positioning and tracing, messaging and security for all types of sea-going vessels. The service applies a vessel-based terminal hosting a GNSS receiver which transmits the navigation status together with messages to a Service Center with a flexible return-link capability. A hybrid space segment is considered comprising the Inmarsat constellation of geostationary communications satellites augmented by two highly inclined low earth orbit satellites for truly global services. Services will be offered to commercial enterprises such as fishing companies as well as public entities such as National Coast Guards. A detailed market analysis has been performed to assess these markets and to determine their penetration. Commercial viability has been proven for business models purely based on Inmarsat and a hybrid space segment using Inmarsat and dedicated micro-satellites. Both cases represent viable businesses in the range of MEUR 100 p.a. Although tailored to a specific market, the approach can be extended to other commercial opportunities requiring space-based communication navigation services.

Gill, Eberhard; Fox, Brian M.; Kreisel, Joerg

2006-07-01

198

New trends in laser satellite communications: design and limitations  

NASA Astrophysics Data System (ADS)

Optical communications offer a capable alternative to radio frequency (RF) communications for applications where high data-rate is required. This technology is particularly promising and challenging in the field of future inter-satellite communications. The term laser satellite communications (LSC) stands for optical links between satellites and/or high altitude platforms (HAPs). However, optical links between an earth station and a satellite or HAPs can be also involved. This work gives an overview of nowadays laser satellite communications. Particularly, it is focused on the factors causing degradation of the optical beam in the atmosphere. If an optical link passes through the atmosphere, it suffers from various influences such as attenuation due to absorption and scattering, intensity fluctuations due to atmospheric turbulence and background radiation. Furthermore, platform vibrations cause mispointing and following tracking losses. Suitable devices and used pointing and tracking system for laser satellite communications are discussed. At the end, various scenarios of the optical links and calculations of their power link budgets and limitations are designed. Implemented software is used for calculation of optical links. This work proves that the Free Space Optics (FSO) systems on mobile platforms, like satellites and HAPs are a promising solution for future communication networks.

Císar, J.; Wilfert, O.; Fanjul-Vélez, F.; Ortega-Quijano, N.; Arce-Diego, J. L.

2008-11-01

199

622 Mbps High-speed satellite communication system for WINDS  

NASA Astrophysics Data System (ADS)

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

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

2006-07-01

200

Low Earth-orbit store-and-forward satellites in the amateur radio service  

Microsoft Academic Search

Several aspects of the most recently launched low-earth-orbit (LEO) store-and-forward satellites operating in the amateur satellite service are described. Included are a description of the satellites and their most interesting implementation details, with particular emphasis on the communications system; a description of the file server and broadcast protocol; a description of operation from the user's viewpoint; and some statistics characterizing

Robert J. Diersing; Greg Jones

1993-01-01

201

Spacecraft If Switch Matrix for Wideband Service Applications in 30/20 Ghz Communications Satellite Systems: Proof-of-Concept Model, Executive Summary.  

National Technical Information Service (NTIS)

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) ...

P. T. Ho E. Coban J. Pelose

1983-01-01

202

The ESA technological development activity for domestic communications satellite systems  

NASA Astrophysics Data System (ADS)

Domestic and rural satellite communications, when compared to more traditional satellite systems such as Intelsat and Eutelsat, present different system requirements which result in different technological solutions both for the space segment and the ground segment. In view of preparing European industry to be competitive in an international 'Call for Tenders' expected for such systems, especially from less developed countries, the European Space Agency started in 1982 a program of technological development of specific components, subsystems, and systems described in this communication. After introducing background concepts of Domestic Communication Satellite Systems, the article reviews the technological developments in both the space segment and the earth segment.

Bichi, A. F.

1986-10-01

203

ICDSC-9 - International Conference on Digital Satellite Communications, Copenhagen, Denmark, May 18-22, 1992, Selected Papers  

NASA Astrophysics Data System (ADS)

Attention is given to a future satellite communications system using millimeter-wave bands and an on-board processor; the role of satellite communications in the integrated services digital network (ISDN) era; architectures for the INTELSAT narrowband ISDN-compatible satellite communications network; on-board baseband switch development using a high-speed optical ring; personal communications via INTELSAT Ku-band transponders; burst-error characterization of FEC coded digital channels; and international fixed satellite systems in synchronous digital hierarchy transport networks. Attention is also given to a review of wideband packet protocols, 250 MHz SAW filters for a subchannel switched frequency division multiple access system employing ST-cut quartz substrates, slotted Aloha multiple access and error control coding for land mobile satellite networks, personal communications by satellite, and a multiaccess phased array antenna simulator for a digital beam-forming system investigation. (For individual items see A93-26227 to A93-26238)

1992-10-01

204

Direct broadcast satellite service implementation in the United States of America  

NASA Astrophysics Data System (ADS)

The roots of direct-to-home broadcast satellite (DBS) service go back to Clarke (1945), who pointed out the advantages of a world-wide communications system employing three geostationary satellites, one over each major ocean. In 1977, the International Telecommunication Union (ITU) developed a plan for the Broadcasting-Satellite Service (BSS) in the 12-GHz band. BSS planning for the Western Hemisphere (ITU Region 2) was deferred until 1983. In 1980, the first U.S. application was filed to construct an experimental DBS system. The Federal Communications Commission (FCC) adopted rules in 1982 for licensing and operating DBS systems. Attention is given to DBS service choices, aspects of low-power DBS-like service, medium-power DBS-like service, high-power DBS service, types of DBS business, DBS systems standards, and technical standards for high-power DBS.

Clark, J. F.

1985-10-01

205

Mugunghwa: The first Korean domestic satellite for FSS and DBS services  

NASA Astrophysics Data System (ADS)

Mugunghwa is the first generation satellite for the Republic of Korea. It uses the advanced digital technology for direct broadcasting and fixed satellite services in Korea. It will provide basic satellite communications facilities with small low-cost remote stations for rural and remote areas presently having inadequate or no telecommunication facilities. It will also provide high speed data and video distributions for business television and other professional program services such as tele-educational video networks. High quality color television and high definition TV services will also be available anywhere in Korea.

Hwangbo, Han

206

Hybrid Satellite-Terrestrial Approach to Aeronautical Communication Networks.  

National Technical Information Service (NTIS)

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 in...

B. A. Kachmar G. J. Chomos J. H. Griner K. S. Martzaklis R. J. Kerczewski S. W. Mainger

2000-01-01

207

Queueing Models for Designing Digital Communication Satellite Systems.  

National Technical Information Service (NTIS)

Satellites have an enormous potential for providing efficient communication links between many widely scattered ground stations. By interpreting the messages as customers in a queueing system, an unusual type of queueing model can be formulated to describ...

F. S. Hillier B. Jabbari

1982-01-01

208

Beyond the Ionosphere: Fifty Years of Satellite Communication.  

National Technical Information Service (NTIS)

Partial Contents: Radio Versus Cable: 'International Telecommunications Before Satellites'; 'Moon in Their Eyes: Moon Communication Relay at the Naval Research Laboratory, 1951-1962'; 'Moon Relay Experiments at Jodrell Bank'; 'Something of Value: Echo and...

A. J. Butrica

1997-01-01

209

Personal communications services: Improving theater deployable communications for the 21st century  

NASA Astrophysics Data System (ADS)

Personal Communications Services (PCS) may be the key ingredient for vastly improved military communications capabilities at the turn of the century. The Federal Communications Commission (FCC) defines PCS as a family of mobile or portable radio communications services which could provide services to individuals and businesses and be integrated with a variety of competing networks ... the primary focus of PCS will be to meet communications requirements of people on the move. Today's generation of Theater Deployable Communications, which provides joint tactical communications to deployed forces, is the Tri-Service Tactical Communications (TRI-TAC) system. A description of TRITAC's family of equipment, network topology, typical employment, and critical limitations is presented in this thesis. Five commercial Mobile Satellite Services (MSS) are described as viable candidates for augmenting existing communications systems. Cellular design principles such as frequency reuse, cell splitting, channel access methods, and propagation factors are also addressed. Finally, a framework for comparison of the candidate MSS systems is proposed as a baseline for further studies into the most beneficial implementation of PCS into theater deployable communications systems for the future.

Cournoyer, Ronald C., Jr.

1994-06-01

210

Global maritime mobile service via satellite - The INMARSAT system now and in the future  

NASA Astrophysics Data System (ADS)

The business and technical aspects of the INMARSAT (International Maritime Satellite Organization) system are reviewed along with its present capabilities and services and future developments now being considered. The initial phase of maritime mobile satellite communications began with the introduction by the U.S. of the Marisat system in 1976, satisfying a commitment made by COMSAT (Communications Satellite Corp.) in 1973 to provide a maritime satellite service. The Marisat Consortium, spun off by COMSAT, launched three satellites in 1973 - one to serve shipping in the Atlantic, one for the Pacific, and the third as a spare; the spare was subsequently positioned over the Indian Ocean so that the three provided almost global coverage. Each satellite was served by a coast earth station with a 13-m antenna; satellite-earth station links operated in the 6 and 4-GHz bands and the ship-satellite links were at 1.5 and 1.6 GHz. Superceding the limited Marisat system, the INMARSAT Organization, established in July 1979 and first in service on Feb. 1, 1982, now provides communications through a system of Marecs, Intelsat-V, and Marisat satellites. With 41 Signatories by mid-1985, the organization consists of an Assembly, a Council, and a Directorate. Services provided include: telephone; facsimile; low-speed data; high-speed data; telex; telegram; distress, urgency and safety communications; shore-to-ship group calls; various information and assistance services. Coast earth stations, ship earth stations, network coordination stations, and the London headquarters and operations control center are described. Future developments will include an expanded capacity network, digital services, and a role in the Future Global Maritime Distress and Safety System that will use radio beacons that will automatically transmit distress messages to land-based emergency centers in the event of a disaster at sea.

Snowball, A. E.

1986-06-01

211

IRECIN Nano-satellite communication system and ground segment  

Microsoft Academic Search

On board resources necessary to perform the mission tasks are very limited in nano-satellites. This paper proposes a real-time multi-processing system for the communication system between ground segment and IRECIN nano-satellite.The first microprocessor is devoted to interface to the rice-transceiver subsystem decoding packet information and the second one is in charge to communicate with the other subsystems through I2C bus.

M. Ferrante; M. Povia; L. Di Ciolo; A. Ortenzi; M. Petrozzi

2005-01-01

212

Advanced maritime communications technology ship-to-shore satellite link  

NASA Astrophysics Data System (ADS)

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.

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

1983-01-01

213

Advanced Technologies and Satellite Services for Enhancing Space Surveillance  

NASA Astrophysics Data System (ADS)

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.

2010-08-01

214

Communications Satellites: Looking Down the Road.  

ERIC Educational Resources Information Center

|The first phase of the satellite component of a worldwide information grid is over. The real problems are beginning now with the evolution of technology that will beam specialized transmissions from higher-powered satellites into smaller antennae perched on ships, airplanes, and rooftops. This is another matter politically, economically, and…

Dizard, Wilson P.

215

Human interfaces for robotic satellite servicing  

NASA Astrophysics Data System (ADS)

On-orbit servicing (OOS) is growing in importance for the sustainment of certain satellite systems. Although it is more economical to replace satellites in many cases, OOS could be beneficial, or even critical, for more expensive satellites such as Space-Based Laser and constellations such as the Global Positioning System. Some future OOS missions including refueling and modular component replacement will be highly autonomous, but there will still be a need for humans to supervise and to recover when unexpected situations arise. Non-routine tasks such as damage repair or optics cleaning will likely require a more significant level of human control. The human interfaces for such activities can include body tracking systems, three-dimensional audio and video, tactile feedback devices, and others. This paper will provide some insights into when and at what level human interaction may be needed for OOS tasks. Example missions will be discussed and the argument will be made that human interfaces are important even for primarily autonomous missions. Finally some current research efforts within NASA, academia and the military will be discussed including research being conducted in the Air Force Research Laboratory at Wright-Patterson Air Force Base.

Ianni, John; Repperger, Daniel; Baker, Robert W.; Williams, Robert L.

2002-06-01

216

Satellite Tactical Communications at High Latitudes.  

National Technical Information Service (NTIS)

Canada spans about 90 degrees of longitude and has requirements for tactical command and control communications as far north as to at least 84 degrees north latitude. These facts create unique problems when considering requirements for communication by sa...

K. L. Matheson

1983-01-01

217

EUTELTRACS: The European Experience on Mobile Satellite Services.  

National Technical Information Service (NTIS)

EUTELTRACS is Europe's first commercially operated Mobile Satellite Service. Under the overall network operation of EUTELSAT, the European Telecommunications Satellite Organization, EUTELTRACS provides an integrated message exchange and position reporting...

J. Colcy R. Steinhaeuser

1993-01-01

218

Applications in Military Communications of Low and Medium Earth Orbit Commercial Satellite Systems.  

National Technical Information Service (NTIS)

At the dawn of the 21st century several Low and Medium Earth Orbit Commercial Satellite constellations will be operational and they will be able to provide high bandwidth Global Communications in voice, data and multimedia services for mobile consumers an...

I. Kakavas

1997-01-01

219

A multi-purpose satellite service at 20/30 GHz - Opportunities and challenges  

NASA Astrophysics Data System (ADS)

The suitability of developing high-frequency bands is evaluated with particular attention given to the use of the 20/30-GHz band for satellite voice, data, and video communications. Crowding in the C- and Ku-band frequencies allocated to fixed-satellite services is examined in the light of continuing growth, and the benefits of establishing general-satellite services (GSSs) are listed. NASA's ACTS program and private GSS systems are delineated and shown to offer high-data-rate fixed-communications antennas and technologies suitable for multiple services. The Norstar satellite is described as an example of a GSS system, and the technical characteristics are given. In spite of technical, operational, and regulatory challenges presented by the development of GSS systems, a GSS allocation can enable the International Telecommunications Union to be proactive in its spectrum/orbit allocations.

Taylor, Leslie

1992-03-01

220

Telecommunication service by leased transponders of the regional satellite  

NASA Astrophysics Data System (ADS)

Various telecommunications applications and services that can be provided by regional satellites are discussed. The potential for extending and enhancing Asia's telecommunications infrastructure is huge; and as Asian countries further develop economically, they will require the speed and power of satellites in order to develop their telecom and television broadcasting facilities quickly and economically. Topics discussed include emergence of regional satellite systems; services offered by regional satellites; rural telecommunication; trunk routes; international links; and television broadcasting.

Jordan, Andrew

221

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

ERIC Educational Resources Information Center

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…

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

222

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

ERIC Educational Resources Information Center

|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…

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

223

Trends in satellite communications and the role of optical free-space communications [Invited  

Microsoft Academic Search

Feature Issue on Optical Wireless Communications (OWC) The communication needs of Earth observation satellites is steadily increasing. Within a few years, the data rate of such satellites will exceed 1 Gbit\\/s, the angular resolution of sensors will be less than 1 murad, and the memory size of onboard data recorders will be beyond 1 Tbyte. Compared with radio frequency links,

Morio Toyoshima

2005-01-01

224

An overview of the communications technology satellite project: Executive summary  

NASA Astrophysics Data System (ADS)

An overview of the Communications Technology Satellite (CTS) project, a joint venture between NASA and the Canadian Department of Communications is given. A brief technical description of the CTS spacecraft and its cognate hardware and operations, a history of the CTS project, and a list of the CTS experiments and demonstrations conducted during the course of the project are given.

Rapp, W.; Ogden, D.; Wright, D.

1982-12-01

225

A digital transmission system for global maritime satellite communications  

Microsoft Academic Search

A digital transmission system for global maritime satellite communications has been designed, and experimental communications equipment has been developed, taking account of its potential application to the Inmarsat system where analog modulation is currently used for telephone signal transmission. This paper discusses possible digital technologies to realize an efficient digital transmission system, and presents a concept for the designed system.

Y. Hirata; Y. Yasuda; H. Okinaka; K. Kashiki

1984-01-01

226

76 FR 50425 - Service Rules and Policies for the Broadcasting Satellite Service (BSS)  

Federal Register 2010, 2011, 2012, 2013

...Lynne Montgomery, Satellite Division, International...increased competition among satellite and terrestrial services...license or U.S. market access. We also recognize...Off-Axis Gain Data. Small variations in satellite orbital...

2011-08-15

227

Management of the fleet satellite communications satellite acquisition for the Naval Postgraduate School  

NASA Astrophysics Data System (ADS)

This thesis discusses the management of the acquisition of the fleet Satellite Communications Satellite (FLTSATCOM) Qualification Model for the Naval Postgraduate School. The preparations, scheduling, and accomplishment of the delivery and the efforts required to establish the FLTSATCO laboratory are discussed. The interaction between the Naval Postgraduate School, various government agencies, and the FLTSATCOM prime contractor necessary to accomplish the project is also described.

Eyler, David E.

1991-06-01

228

Land Mobile Communications Satellite Missions (LAMOCOSAMIS) Task 2: Functional Requirements.  

National Technical Information Service (NTIS)

Existing, planned, and foreseeable land mobile communication services in Europe were reviewed. Functional characteristics of available and new services were studied. Assumptions on global architecture were made. Regulatory aspects were investigated. The s...

1985-01-01

229

47 CFR 101.1013 - Permissible communications services.  

Code of Federal Regulations, 2012 CFR

...false Permissible communications services. 101...Telecommunication FEDERAL COMMUNICATIONS COMMISSION (CONTINUED) SAFETY...render any kind of communications service consistent with the Commission's rules and...

2012-10-01

230

47 CFR 101.1013 - Permissible communications services.  

Code of Federal Regulations, 2011 CFR

...false Permissible communications services. 101...Telecommunication FEDERAL COMMUNICATIONS COMMISSION (CONTINUED) SAFETY...render any kind of communications service consistent with the Commission's rules and...

2011-10-01

231

47 CFR 73.667 - TV subsidiary communications services.  

Code of Federal Regulations, 2012 CFR

...false TV subsidiary communications services. 73...Telecommunication FEDERAL COMMUNICATIONS COMMISSION (CONTINUED) ...667 TV subsidiary communications services. (a...required to apply to the FCC for the...

2012-10-01

232

47 CFR 73.295 - FM subsidiary communications services.  

Code of Federal Regulations, 2012 CFR

...false FM subsidiary communications services. 73...Telecommunication FEDERAL COMMUNICATIONS COMMISSION (CONTINUED) ...295 FM subsidiary communications services. (a...required to apply to the FCC for the...

2012-10-01

233

High capacity satellite communication system and key technologies  

Microsoft Academic Search

A high-capacity satellite communication system for Japan, with multiple beams and key technologies for onboard equipment, is described. The system will provide trunk transmission, digital business communication, and mobile communication. Advantages of the multibeam system include increased transmission capacity, reduction in earth-station antenna diameter, and frequency reuse. Onboard technologies discussed include cluster-feed horn design, reflector deployment, antenna pointing control (accurate

Y. Nagai; S. Okasaka; K. Nakagawa

1986-01-01

234

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

ERIC Educational Resources Information Center

|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…

Texas Education Agency, Austin.

235

Role of Communications Satellites in the National and Global Information Infrastructure.  

National Technical Information Service (NTIS)

Early in 1995, the Satellite Industry Task Force (SITF) was initiated by executives of the satellite industry to define the role for communication satellites in the National and Global Information Infrastructure (NII/GII). Satellites are essential to this...

1996-01-01

236

The principle of a navigation constellation composed of SIGSO communication satellites  

NASA Astrophysics Data System (ADS)

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.

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

2013-04-01

237

Emerging communication technologies in emergency medical services  

Microsoft Academic Search

Advances in communication technologies are changing the face of emergency medical services (EMS). Two communication technologies in particular—cellular-enhanced 9-1-1 service and automatic crash notification (ACN)—will have a considerable impact on EMS. Although enhanced 9-1-1 service from land-line phones is now available in nearly every EMS system across the country, enhanced 9-1-1 service from cell phones currently does not exist. With

Richard C. Hunt

2002-01-01

238

Ionospheric scintillation effects on UHF satellite communications  

Microsoft Academic Search

Naturally induced high altitude ionization will cause signal scintillation effects that are of great importance to the design and deployment of military satellite systems employing frequencies below 1 GHz. The scintillation will result in Rician or Rayleigh signal fading with finite signal decorrelation time and limited coherent bandwidth of the transmission channel

P. A. Kullstam; M. J. Keskinen

2000-01-01

239

Personal communications: An extension to the mobile satellite  

NASA Astrophysics Data System (ADS)

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.

Epstein, Murray; Draper, Francois

240

Alternative Visions of Satellite Communication Economics in the 2010-2020 Time Period  

NASA Astrophysics Data System (ADS)

Satellite communications technologies have been gradually improving for over 35 years. Quality and reliability of equipment and services increased dramatically from the 1960s until the early 1980s. In the last 20 years improvements have been progressing steadily but in less dramatic fashion. This paper addresses three new satellite technologies that may be able to rekindle the very rapid prior growth pattern and achieve dramatic new systems economies in the 2010 to 2020 time period. The future could thus see the extension of conventional satellite technologies that produces a scenario in which satellite economics may become progressively less competitive with alternative telecommunications systems. On the other hand the authors explore three possible new technologies that produce alternative economic scenarios for the future. These are: 1) a tethered geo platform network, 2) advanced peizo-electric shaped antennas on a geo platform system, and 3) a geo platform that is constituted by a swarm of nanosatellites. Each of these systems requires significant new research and development. Which of these, if any, will form part of the successful satellite communications designs in the future is unclear at present. Each alternative, however, promises progressive economic cost reductions that could make future satellite networks highly competitive for a variety of broadband services and, potentially, even with some fiber optic transmissions. This paper outlines the technology needed for future competitiveness in such satellite systems, and creates an economic model that analyzes the potential viability and profitability of each system. Further analysis examines the overall business cases. These also test the sensitivity of these systems to more reliable and less costly new launch systems that, if available, would both accelerate the deployment of new satellite communications technologies as well as decrease the cost of all satellite systems.

Pelton, Joseph N.

2002-01-01

241

Service outages in GPS associated with satellite failures  

Microsoft Academic Search

The planned NAVSTAR\\/GPS satellite constellation of 18 satellites plus 3 active spares will provide excellent coverage over the CONUS if all are operating properly. This report examines the coverage under conditions of one satellite failure. It turns out that the failure of any satellie results in service outages of up to half an hour somewhere in the CONUS. While altimeter

R. M. Kalafus

1984-01-01

242

EHF for Satellite Communications: The New Broadband Frontier  

Microsoft Academic Search

The exploitation of extremely high-frequency (EHF) bands (30-300 GHz) for broadband transmission over satellite links is currently a hot research topic. In particular, the Q-V band (30-50 GHz) and W-band (75-110 GHz) seem to offer very promising perspectives. This paper aims at presenting an overview of the current status of research and technology in EHF satellite communications and taking a

Ernestina Cianca; Tommaso Rossi; Asher Yahalom; Yosef Pinhasi; John Farserotu; Claudio Sacchi

2011-01-01

243

Thin-route rural communications using Intelsat satellites  

NASA Astrophysics Data System (ADS)

Application requirements exist and are growing in developing countries for telecommunications services that can be supplied best by use of satellite technology. Many of these requirements can be satisfied with one or two telephone circuits per earth station location. In many areas of the world, the only satellite capacity available to support these thin-route service requirements is in the Intelsat system. Small earth stations, suited economically and sized to provide the required thin-route service capacity, have not been common in the Intelsat system. However, Intelsat is recognizing the need for thin-route services and the opportunities that will develop for providing these services using small earth stations in the Intelsat system. This paper explores the potential advantages of continuously-variable-slope delta modulation (CVSD) voice encoding and the technical parameters of small earth stations suited for thin-route services, as well as the developments within Intelsat for responding to these service needs.

Jennings, R. D.; McManamon, P. M.

244

A digital satellite communications system for SPRINT  

NASA Astrophysics Data System (ADS)

Switched voice, digital data and private line traffic are scheduled to be implemented in 1984-1988 by a digital satellite system encompassing the Spacenet and Gstar satellites. This system features TDMA terminals operating at 60, 90, and 120 Mbps with 36, 54 or 72 MHz-bandwidth transponders, respectively. The network topology will identify two application types: that designated 'on-net', whose earth stations will be strategically located at major junctions of the existing microwave backbone, near the larger cities, and will carry long haul, heavy route traffic between those junctions; and that designated 'off-net', whose earth stations are located off the microwave backbone at smaller cities and will access the backbone, and thence the entire SPRINT network, via gateway earth stations located at major junction sites.

Pourmand, B.; Jacobs, A.

245

Service Learning's Foothold in Communication Scholarship.  

ERIC Educational Resources Information Center

|Considers how much of an impact service learning pedagogies have had among those who teach journalism and mass communication. Attempts to fill the research void by assessing the current state of this pedagogical movement within the journalism/mass communication discipline, and suggests that a formal process for incorporating service learning into…

Panici, Daniel; Lasky, Kathryn

2002-01-01

246

Theater/user-dedicated communications satellite system concept  

NASA Astrophysics Data System (ADS)

The results of an ongoing study of a theater/user-dedicated communications satellite system concept, which would augment the existing satellite systems (DSCS and MILSTAR), are presented. The system attempts to satisfy a user requirement in incremental amounts. The study entails requirements analysis, concept exploration, and cost and risk analysis. User requirements are determined from contact with theater users, from requirements generated by other ongoing studies, and from requirements compiled by US Air Force Space Command. The study defined and evaluated ground and space systems and communications payload concepts. Some of the issues analyzed during the study include system capacity, compatibility, and interoperability with other systems; satellite orbit; constellation size; survivability; responsiveness; and launch options. Communications signal options analyzed were RF frequency, modulation, and link power margins in order to determine system capacity and antijam performance. Command and control concepts and issues were also addressed. A wide variety of potential communications payload concepts that meet the needs of present satellite users were explored, primarily in the SHF and EHF frequency regimes. All payload concepts were evaluated with the intent of minimizing the satellite size, weight, power, risk, and cost.

Bennett, Roger R.

247

Design and characteristics of a multiband communication satellite antenna system  

NASA Astrophysics Data System (ADS)

Feasibility studies on a multiband communication satellite antenna system and the key technologies involved in devising this system are described. The proposed multiband communication satellite utilizes four frequency bands: Ka (30/20 GHz), Ku (14/12 GHz), C (6/4 GHz), and S (2.6/2.5 GHz). It has six beam configurations, three multibeam and three shaped-beam. The following key technologies are presented: (1) a low-loss frequency selective subreflector (FSR) for compact feeds, (2) a low-loss and broadband frequency selective surface (FSS), and (3) a highly accurate and reliable mesh reflector.

Ueno, Kenji; Itanami, Takao; Kumazawa, Hiroyuki; Ohtomo, Isao

1995-04-01

248

Italsat, an advanced on board processing satellite communication system  

NASA Astrophysics Data System (ADS)

The paper presents the Italsat satellite communication system developed by the Italian Space Agency. The system is based on a regenerative switching satellite payload operating at 20 and 30 GHz. The coverage of the Italian territory is achieved by six spot beams controlled by an antenna fine pointing subsystem. This payload is called multibeam payload. A second communication payload covers Italy with a global beam. This payload has three transparent transponders at 20 and 30 GHz. To establish an operative system a second flight unit is now in production. The launch is expected the end of 1993. The operative system will provide up to 24,000 bidirectional telephone connections.

Marconicchio, F.; Morelli, G.; Valdoni, F.

1992-03-01

249

Implementation of a land mobile terminal for satellite data communication  

NASA Astrophysics Data System (ADS)

A prototype for a Land Mobile Terminal (LMT) to perform in-field experimentation and validation activities on the mobile - satellite - shore station link, and to confirm the validity of the proposed LMT implementation was developed for PRODAT. The PRODAT LMT will be a two way system for demonstrating a data only communication at low data rate between land mobile users and a network managing system using the MARECS-A satellite and future dedicated satellites. The terminal consists of the antenna, plus an RF box, below roof equipment, and user interface.

Valsasina, G. B.

1986-09-01

250

Millimeterwave regions for satellite communications (spread-spectrum considerations)  

NASA Astrophysics Data System (ADS)

This paper discusses the choice of spread-spectrum satellite system frequency bands which offer large allocated bandwidth, low attenuation, and large coherent bandwidths. Many millimeter wave regions offer large allocated bandwidth, and atmospheric attenuation and coherent bandwidth to estimate which bands may be useful for spread spectrum satellite communication is examined. First, maximum signal/interference regions (for antennas of constant aperture) are found in the 2-90 GHz region. Next, wide frequency allocations at millimeter wave frequencies are noted to cause upward adjustments in frequency selection. Lastly, satellites in both an inclined 24-hour orbit ('Walker Orbit') and an inclined elliptic orbit (Molniya Orbit) were found to have useful bandwidths.

Kamal, A. K.; Christopher, P. F.

251

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

NASA Astrophysics Data System (ADS)

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

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

2002-01-01

252

Broadband and scalable mobile satellite communication system for future access networks  

NASA Astrophysics Data System (ADS)

Due to the recent market trends, NTT has begun research into next generation satellite communication systems, such as broadband and scalable mobile communication systems. One service application objective is to provide broadband Internet access for transportation systems, temporal broadband access networks and telemetries to remote areas. While these are niche markets the total amount of capacity should be significant. We set a 1-Gb/s total transmission capacity as our goal. Our key concern is the system cost, which means that the system should be unified system with diversified services and not tailored for each application. As satellites account for a large portion of the total system cost, we set the target satellite size as a small, one-ton class dry mass with a 2-kW class payload power. In addition to the payload power and weight, the mobile satellite's frequency band is extremely limited. Therefore, we need to develop innovative technologies that will reduce the weight and maximize spectrum and power efficiency. Another challenge is the need for the system to handle up to 50 dB and a wide data rate range of other applications. This paper describes the key communication system technologies; the frequency reuse strategy, multiplexing scheme, resource allocation scheme, and QoS management algorithm to ensure excellent spectrum efficiency and support a variety of services and quality requirements in the mobile environment.

Ohata, Kohei; Kobayashi, Kiyoshi; Nakahira, Katsuya; Ueba, Masazumi

2005-07-01

253

Millimeter wave advantages for satellite communications  

NASA Astrophysics Data System (ADS)

The benefits of millimeter-wave systems are demonstrated by defining optimal satellite uplink and downlink frequencies in a crowded commercial environment for fixed-size systems. The analysis utilizes a rain attenuation model to determine the total atmospheric attenuation versus frequency. It is inferred that atmospheric attenuation is often reasonable for elevation angles greater than 30 degrees even in a severe rain region (Florida). For constant-size systems, then, the preferable uplink frequencies were found to be greater than 20 GHz, and for downlink frequencies, greater than 40 GHz.

Christopher, P.

254

Communications satellite developments: Technology; Communications Satellite Systems Conference, 5th, Los Angeles, Calif., April 22-24, 1974, Technical Papers  

Microsoft Academic Search

Aspects of spacecraft technology are considered, taking into account efficient high-capacity communications satellites, a constrained lens antenna for multiple-beam satellites, an ATS-6 interferometer, the development and the air bearing test of a double-gimballed momentum wheel attitude-control system, and the advantages of nuclear power systems compared to the current solar systems. Aspects of terminal technology are discussed along with subjects of

W. G. Schmidt; G. E. Lavean

1976-01-01

255

Study on Satellite Communications using Ultra Wideband (UWB) Signals  

Microsoft Academic Search

In this paper, the possibility of satellite communication systems using a multiband UWB signal format is considered. For terrestrial short-distance high-speed communications, multiband UWB schemes are proposed in IEEE 802.15 TG3a and the discussion is ongoing at the standardization body. In the multiband UWB scheme, frequency hopping is adopted over 3.1 - 10.6 GHz, which is regulated by the FCC

Yoshio KUNISAWA Hiroyasu ISHIKAWA; Hisato IWAI; Hideyuki SHINONAGA

256

Propagation losses for satellite-to-submarine optical communication systems  

Microsoft Academic Search

Water absorption characteristics limit the useable electromagnetic carrier frequencies for underwater communication to either less than a few hundred hertz (ELF) or the blue-green optical wavelengths. This paper considers the case of a satellite-borne blue-green laser transmitter communicating at low data rates to a deeply submerged receiver. One difficulty in designing such a system is the uncertainty in propagation losses.

G. Lee; G. Schroeder; C. Ciany

1978-01-01

257

Customer Premise Service Study for 30/20 Ghz Satellite System.  

National Technical Information Service (NTIS)

Satellite systems in which the space segment operates in the 30/20 GHz frequency band are defined and compared as to their potential for providing various types of communications services to customer premises and the economic and technical feasibility of ...

R. T. Milton D. P. Ross A. R. Harcar P. Freedenberg D. Schoen

1983-01-01

258

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

ERIC Educational Resources Information Center

|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…

Casewell, I. E.

1992-01-01

259

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

ERIC Educational Resources Information Center

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…

Eva, Nicole C.

2012-01-01

260

Satellite broadcasting in Europe  

Microsoft Academic Search

Three main communications services are recognized by the International Telecommunications Union: the Fixed Service, the Mobile Service and the Broadcasting Service. In Europe, EUTELSAT has just begun to exploit the first ECS satellite. The ESA-launched satellite was originally designed to provide an international public telecommunication service, however, the satellite will be used now almost exclusively for TV program distribution, while

P. Bartholome

1984-01-01

261

Caribbean Regional Communications Service Study. Report.  

ERIC Educational Resources Information Center

A follow-up to a limited experiment with the use of satellites in education and public service conducted by the University of the West Indies (UWI) in 1978, this study explores the feasibility of providing a number of services, which would include an extension system based on the use of the UWI telecommunications network. The study was designed to…

Lalor, Gerald C.

262

Design of Experiments to Quantify Communication Satellite System Performance.  

National Technical Information Service (NTIS)

The report describes the steps for designing experiments to quantify the performance of a communication satellite system according to the methods specified by ANS X3.141. Performance is described in terms of performance parameters that are user-oriented a...

R. D. Cass M. J. Miles

1990-01-01

263

Hardware Realization of Modified CIC Filter for Satellite Communication  

Microsoft Academic Search

Cascaded Integrated Comb (CIC) filters are mainly used as low pass filter in rate converter module in a multi rate signal processing based systems. Hardware implementation of CIC filter is very efficient as it does not require any multiplier and uses very less memory. The paper presents the FPGA implementation of modified Cascaded Integrated Comb (CIC) filter for satellite communication

Satish Sharma; Sunil Kulkarni; M. Vanitha; P. Lakshminarsimhan

2010-01-01

264

Multiple beam lens antenna for LEO communication satellite  

Microsoft Academic Search

The design of a multiple beam antenna system for a low earth orbiting (LEO) cellular communication satellite is a topic of current interest. A typical uplink requirement is to provide a number of closely overlapping beams to illuminate Earth-fixed super cells at Ka band. These cells span a field of view of approximately ±40° degrees in elevation and azimuth. Their

K. K. Chan; R. Blasing; B. Wallace

1996-01-01

265

Multiquantum well beam-steering device for laser satellite communication  

Microsoft Academic Search

With the increasing interest in laser satellite communications, new methods are sought to solve the existing problems of accurate and rapid laser beam deflection. Current solutions in the form of galvanometers or piezo fast steering mirrors with one or two degrees of freedom are bulky, power-consuming and slow. The Multi-Quantum Well (MQW) is a semiconductor device with unique potential to

Roee Lahat; Itamar Levy; Shlomi Arnon

2002-01-01

266

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

267

77 FR 48584 - Tenth Meeting: RTCA Special Committee 222, Inmarsat Aeronautical Mobile Satellite (Route) Services  

Federal Register 2010, 2011, 2012, 2013

...Committee 222, Inmarsat Aeronautical Mobile Satellite (Route) Services AGENCY: Federal Aviation...Committee 222, Inmarsat Aeronautical Mobile Satellite (Route) Services...Committee 222, Inmarsat Aeronautical Mobile Satellite (Route) Services. DATES: The...

2012-08-14

268

77 FR 30046 - Ninth Meeting: RTCA Special Committee 222, Inmarsat Aeronautical Mobile Satellite (Route) Services  

Federal Register 2010, 2011, 2012, 2013

...Committee 222, Inmarsat Aeronautical Mobile Satellite (Route) Services AGENCY: Federal Aviation...Committee 222, Inmarsat Aeronautical Mobile Satellite (Route) Services...Committee 222, Inmarsat Aeronautical Mobile Satellite (Route) Services. DATES: The...

2012-05-21

269

75 FR 63534 - Seventh Meeting-Special Committee 222: Inmarsat Aeronautical Mobile Satellite (Route) Services  

Federal Register 2010, 2011, 2012, 2013

...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...

2010-10-15

270

76 FR 66350 - Eighth Meeting: RTCA Special Committee 222 Inmarsat Aeronautical Mobile Satellite (Route) Services  

Federal Register 2010, 2011, 2012, 2013

...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 for the Eighth...

2011-10-26

271

Communications Satellites: A New Channel for International Communications, A New Source of International Tension.  

ERIC Educational Resources Information Center

|Communications satellites could be the subject of bitter and potentially dangerous international controversy. They threaten to upset the comfortable monopoly of internal national communications systems which have enrolled national governments to screen intrusions of unwanted information or ideas. The United Nations Working Committee on Direct…

Mickelson, Sig

272

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

NASA Astrophysics Data System (ADS)

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 geostationary communication satellites and collected extensive satellite anomaly and telemetry data since 1990. Over the course of the past twenty years, the satellites have experienced more than 226 single event upsets (SEUs), a catch-all term for anomalies that occur in a satellite's electronics such as bit-flips, trips in power supplies, and memory changes in attitude control systems. While SEUs are seemingly random and difficult to predict, we correlate their occurrences to space weather phenomena, and specifically show correlations between SEUs and solar proton events (SPEs). SPEs are highly energetic protons that originate from solar coronal mass ejections (CMEs). It is thought that when these particles impact geostationary (GEO) satellites they can cause SEUs as well as solar array degradation. We calculate the associated statistical correlations that each SEU occurs within one day, one week, two weeks, and one month of 10 MeV SPEs between 10 - 10,000 particle flux units (pfu). However, we find that SPEs are most prevalent at solar maximum and that the SEUs on Inmarsat's satellites occur out of phase with the solar maximum. Ultimately, this suggests that SPEs are not the primary cause of the Inmarsat SEUs. A better understanding of the causal relationship between SPEs and SEUs will help the satellite communications industry develop component and operational space weather mitigation techniques as well as help the space weather community to refine radiation models.

Lohmeyer, W. Q.; Cahoy, K.; Liu, Shiyang

273

Vibration-induced jitter control in satellite optical communication  

NASA Astrophysics Data System (ADS)

Laser satellite communication has become especially attractive in recent years. However, because the laser beam is very narrow and there is a long distance between satellites, the laser communication channel is very sensitive to vibrations of the optical platform. These vibrations cause optical jitter, leading to the reduction of received signals and bit-error rate degradation. Consequently, optical jitter control with PAT (pointing acquisition and tracking) subsystems is a critical problem in laser satellite communication. To compensate for the platform vibration effectively in realtime, in this paper, an adaptive feedback control technique based on Youla-parameterization is presented, which can adapt to the current disturbance acting on the laser beam by adjusting its parameters in realtime to maintain optimal performance. The main idea is to use the well-known Youla parameterization formula to construct a feedback control scheme with the guaranteed closed loop stability, and the feedback controller is a function of plant coprime factors and a free parameter Q. For adaptive disturbance estimation, the free parameter Q is set to an adaptive finite impulse response (FIR) filter, the coefficients of which are updated by a recursive least-squares (RLS) algorithm in realtime. It is shown in experiment that the adaptive feedback control technique based on Youla-parameterization can reject the optical jitter caused by satellite platform vibration effectively and improve the performance of the system.

Xue, Zheng-yan; Qi, Bo; Ren, Ge

2013-08-01

274

Application of Propagation Data to VHF Satellite Communication and Navigation Systems.  

National Technical Information Service (NTIS)

Contents: Introduction to VHF satellite navigation and communications systems; Ionospheric limitations on performance on VHF navigation and communication satellite systems; The formation of ionospheric irregularities; Amplitude, phase and angle of arrival...

1970-01-01

275

Planning for the Broadcasting-Satellite Service in the United States of America  

NASA Astrophysics Data System (ADS)

The state of the Western Hemisphere's Broadcasting Satellite Service (BSS) system will be determined at the International Telecommunications Union 1983 Regional Administrative Radio Conference (RARC-83) for Region 2. A discussion is presented of the opportunities and problems presented by BSS in the U.S., and mechanisms by which the Federal Communications Commission (FCC) is integrating private sector advice into its planning for the conference are considered. Among the services purveyed by applicants to the Direct Broadcast Satellite (DBS) system are sponsored rebroadcast, subscription, and leased channels.

Clark, J. F.

1981-09-01

276

Personal communications services: the next technological revolution  

Microsoft Academic Search

The US Federal Communications Commission (FCC) has issued a Notice of Inquiry (NOI) to consider whether to allocate frequencies for personal communications services (PCS), the particular PCS offerings to authorize, the technical standards that licensees should follow, and the regulatory policies tha should govern PCS operations, including who may be eligible for PCS licenses. An overview is given of the

R. M. Singer; D. A. Irwin

1991-01-01

277

22 CFR 123.27 - Special licensing regime for export to U.S. allies of commercial communications satellite...  

Code of Federal Regulations, 2013 CFR

...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...

2013-04-01

278

Operation of communications satellite systems during crisis and conflict  

NASA Astrophysics Data System (ADS)

U.S. military communications satellites can provide an impressive capability for command and control. Whether the combat forces will be able to make effective use of this capability depends on the operational management of the systems. Today, control of COMSAT systems optimizes their use to support a single mission or class of missions. In conflict it will be necessary to allocate capacity based on mission priority rather than peacetime operational concepts. A satellite control network tied to the JSC through the Space Defense Operations Center would allow rapid reallocation of capability to support wartime and crisis requirements without jeopardizing the role of the operational manager.

Dickman, R. L.

279

Advanced technology in satellite communication antennas: Electrical and mechanical design  

NASA Astrophysics Data System (ADS)

Antenna technology for earth stations and satellites is discussed. The fundamentals, including common analysis methods, for antenna technology for satellite communication are reviewed. Details of the analysis method for beam waveguide feeds are shown, and electrical and mechanical designs for earth station antennas are examined. Offset dual-reflector antennas and offset reflector antennas with beam waveguide feed are examined, giving comprehensive descriptions of mechanical techniques. The homology design technique for very large and precise antennas and the holographic measurement method of reflector surface error are discussed. Shaped-beam and multibeam antennas are addressed, as is product assurance.

Kitsuregawa, Takashi

280

Mitigation of log-on rush phenomenon in aeronautical satellite data communication  

Microsoft Academic Search

Satellite data communication using geostationary satellites has been introduced for oceanic air traffic control (ATC). Each aircraft needs to log on to a ground earth station (GES) through a satellite before it starts data transmission and log off to finish the communication at the end of a flight. Several hundred aircraft use the link through a satellite at busy times.

Y. Sumiya; A. Ishide

2009-01-01

281

Comparison of Satellite and Fiber Optics Technologies for Intercity and Intercontinental Communications  

Microsoft Academic Search

The applications of satellite and fiber optic technologies to the design of intercity and intercontinental communications networks are examined. Satellite technology including space and ground segments, and advancements and operational requirements for underwater and land fiber optics communications systems are discussed. Communications satellites and fiber optics are compared in terms of physical implementation, switching requirements, transmission parameters, availability, cost, system

M. Hossein Sharifi; Mohammed Arozullah

1986-01-01

282

Technical and economic feasibility of integrated video service by satellite  

NASA Astrophysics Data System (ADS)

A feasibility study is presented of utilizing modern satellite technology, or more advanced technology, to create a cost-effective, user-friendly, integrated video service, which can provide videophone, video conference, or other equivalent wideband service on demand. A system is described that permits a user to select a desired audience and establish the required links similar to arranging a teleconference by phone. Attention is given to video standards, video traffic scenarios, satellite system architecture, and user costs.

Price, K. M.; Kwan, R. K.; White, L. W.; Garlow, R. K.; Henderson, T. R.

1992-03-01

283

Economic case for the retirement of geosynchronous communication satellites via space tugs  

NASA Astrophysics Data System (ADS)

Both the United Nations (UN) and the US Federal Communications Commission (FCC) have published a ruling that calls for geostationary earth orbit (GEO) satellites to be placed in a disposal orbit at the end of their operational lives. Current procedures utilize spacecraft residual propellant and represent a major life-limiting factor for GEO satellites. An alternative approach would be to allow a space tug to capture and move the satellites after all of their fuel has been exhausted. This extended lifetime can provide significant additional revenue to some satellite operators. Before committing to such a capability, however, the lifecycle costs of a space tug infrastructure must be carefully weighed against the opportunity costs of the current retirement practice. This paper investigates the questions of tug costs, perceived benefits, and service fee. It builds a framework that can be used in evaluating various on-orbit servicing opportunities and proposes that the service fee should be charged as a percentage of the additional revenue received by the satellite operators and analyzes how cost estimation uncertainties affect the value of on-orbit tugging. The presented analysis concludes that until advanced propulsion systems gain greater use, retirement via a space tug will be of value for the 10 20 most expensive GEO assets.

Galabova, Kalina K.; de Weck, Olivier L.

2006-05-01

284

Short Messaging Services using TDRSS with low-power Personal Communication Devices  

Microsoft Academic Search

The Tracking and Data Relay Satellite (TDRS) and the TDRS System (TDRSS) form the basis for NASA's Space Network (SN) originally intended for manned spaceflight communications. While admirably serving this function, the TDRSS can also provide alternate communications for a variety of low-power operational requirements. This includes the use of Short Messaging Services (SMS) with personal-sized devices where small amounts

Jerry Brand

2011-01-01

285

Design and performance of a repeater for optical satellite communication  

NASA Astrophysics Data System (ADS)

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

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

286

The flexural behavior of PACSAT (passive communication satellite) in orbit  

NASA Astrophysics Data System (ADS)

This report presents an analysis of the libration and vibration of a passive communications satellite known as PACSAT. It addresses the effects of various disturbing mechanical forces on verticality and straightness. Phenomena considered include orbital ellipticity, earth oblateness, solar and lunar gravity, radiation pressure, micrometeorial impacts, and thermal bending effects. The last two are the most important. It is concluded that the flexural misbehavior of PACSAT in orbit is such that it is most improbable that the present design (unsupported linear array) can perform its communications functions.

Sollfrey, W.

1983-02-01

287

Economy of modularized communication platforms and satellite clusters  

NASA Astrophysics Data System (ADS)

Results from an ESA cost-benefits analysis of modularized communication platforms and satellite clusters are reviewed. Attention was given to a reference satellite based on current technology, and advanced candidates for television broadcasting from a 19 deg W GEO modularized units and clusters. Both the Ariane and the Shuttle were considered as the launch vehicles for large, autonomous satellites, co-orbiting cluster units, or modular platofrms to be assembled in GEO. The analyses included development of performance and specific requirements, and cost comparison. Cost components comprised the spacecraft, constant costs, space segment costs, operations, and total system costs for a direct television broadcast system for Europe. An Ariane-launched modular platform was projected to cost 60% of the reference system, with break-even occurring at the addition of the third payload module.

Kleinau, W.; Nauck, J.; Hansell, P.

1982-09-01

288

A planar wideband circularly polarized antenna for satellite communications  

Microsoft Academic Search

A planar wideband circularly polarized antenna for Ku-band satellite communications is presented. The antenna consists of an array of bow-tie antennas printed on a thin dielectric substrate that is fed through a corporate feed divider network. The array is backed by a low dielectric substrate coated with a metallized ground plane to provide one-sided radiation. This configuration is sandwiched by

D. F. Filipovic

1999-01-01

289

SAW-based IF Processors for mobile communications satellites  

NASA Astrophysics Data System (ADS)

Future generation mobile communications satellite must operate with very limited spectrum allocations and hence require sophisticated on-board processing to provide efficient spectrum management. This paper discusses the use of a complex Surface Acoustic Wave based, IF Processor which will perform the signal processing functions on Inmarsat 3. Comprehensive experimental performance data, obtained from a COM DEV internally funded program has clearly demonstrated the design and implementation to be optimum for the Inmarsat 3 program.

Kovac, Robert; Lee, Mike; Miller, Nigel; Peach, Robert; Swarup, Arvind; van Osch, Brent; Veenstra, Arnold

1991-10-01

290

Land mobile communications and position fixing using satellites  

Microsoft Academic Search

In a recent series of experiments, the General Electric Corporate Research and Development Center demonstrated effective satellite-aided land mobile communications, analog and digital data relay, and automatic real-time vehicle position fixing. In one sequence of tests a station wagon was equipped with a specially designed antenna, a slightly modified commercial VHF transceiver, and a digital tone-code ranging responder that operated

AXEL F. BRISKEN; ROY E. ANDERSON; RICHARD L. FREY; JAMES R. LEWIS

1979-01-01

291

Multi-gigabit laser communications for satellite cross-links  

Microsoft Academic Search

Nd:YAG space laser communications systems are being developed with multi-gigabit capability. A 1 Gbps system Engineering Feasibility Model which has been tested successfully both functionally and environmentally, has led to further designs for space qualified multi-gigabit packages. A system configuration for a 2 Gbps duplex cross-link between synchronous satellites is described. The 2 Gbps transceiver characteristics are addressed in detail

J. A. Maynard; M. Ross; J. D. Wolf

1979-01-01

292

IRECIN Nano-satellite communication system and ground segment  

NASA Astrophysics Data System (ADS)

On board resources necessary to perform the mission tasks are very limited in nano-satellites. This paper proposes a real-time multi-processing system for the communication system between ground segment and IRECIN nano-satellite. The first microprocessor is devoted to interface to the rice-transceiver subsystem decoding packet information and the second one is in charge to communicate with the other subsystems through I2C bus. It uses UHF band and less than 1 W in RF. All electronic components are SMD technology in order to reduce weight and size. The realized electronic boards are completely developed, realized and tested at the Vitrociset S.P.A. under control of Research and Develop Group. This multi-processor system even allows managing the tasks of the microprocessor eventually damaged, the microprocessor still working takes the functionalities of the first one using simpler algorithms. This choice assures an increasing nano-satellite life time. Moreover, the depicted method allows to free the on-board main microprocessor from the control functions of the communication data, increasing its communication capabilities with the other subsystems. The proposed system is implemented on the IRECIN, a modular nano-satellite weighing less than 1.5 kg, constituted by 16 external sides with surface-mounted solar cells and three internal Al plates, kept together by four steel bars. Lithium-ion batteries are added for eclipse operations. Attitude is determined by two three-axis magnetometers and the solar panel data. Control is provided by an active magnetic control system. The spacecraft will be spin-stabilized with the spin-axis normal to the orbit.

Ferrante, M.; Povia, M.; di Ciolo, L.; Ortenzi, A.; Petrozzi, M.

2005-01-01

293

Aiding GPS With Additional Satellite Navigation Services.  

National Technical Information Service (NTIS)

In modern warfare navigation services are very important. GPS is currently providing service for accurate navigation, except in some areas, especially urban areas, where GPS signals cannot always be tracked by users. In these cases some additional navigat...

Y. A. Mutlu

2010-01-01

294

The current status of Russian/CIS communication satellites  

NASA Astrophysics Data System (ADS)

As part of a Memorandum of Understanding (MOU) signed by U.S. President George Bush and Russian President Mikhail Gorbackev during a July 1991 summit meeting, the U.S. agreed to expand civil space cooperation with the Russian Federation and the Commonwealth of Independent States (CIS). The goal of the MOU was to increase the technical capabilities of both sides to respond to both natural and man-made disasters and top benefit from the capabilities and involvement of international and non-government organizations. This summit agreement has allowed the Russian Federation to offer unprecedented commercial and emergency relief access to their on-orbit communications satellites. This thesis presents a brief history of the Soviet/Russian communication satellite program, and an examination of current systems as well as future and on-order systems. Simulations were conducted to determine the useability of the major systems (Gorizont, Ekran, Molniya, and Raduga) from 17 geographic locations. This is concluded with an introduction to the Telemedicine Space-bridge Project that is a direct result of the Bush-Gorbachev summit, and a shining example of Russian/U.S. cooperation in the satellite communication arena.

Ninas, Larry E.

1994-09-01

295

Television satellite data broadcasting systems and services  

Microsoft Academic Search

Recently, the industry has recognized the importance of television data broadcasting systems for a wide range of services, not limited to stock exchanges. Such services have proved to be essential also for database maintenance, software delivery and\\/or updating, news broadcasting, and a wide range of other free and payment services, where the same amount of data has to be delivered

Fabrizio Sestini

1996-01-01

296

Digital sound service for direct broadcasting satellites  

NASA Astrophysics Data System (ADS)

A 16 channel (4 phase (CPSK), or 12 channel (2 phase CPSK) digital sound link for the TV Sat satellite is proposed. Small parabolic antennas suitable for sound and TV broadcasts assure reception. A specially developed tuner allows the user to select either a given program from 1 of 16, or 1 of 8 types of program, e.g., sport or opera. Tests with OTS satellite and a cable distribution network prove the feasibility of the proposal. Encoding, transmission, signal modulation and links are outlined. Equipment is described.

Treytl, D.

297

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

NASA Astrophysics Data System (ADS)

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

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

1986-11-01

298

The Aquila launch service for small satellites  

Microsoft Academic Search

The Aquila launch vehicle is described emphasizing its use in the deployment of small satellites for the commercial sector. The Aquila is designed to use a guidance, navigation, and control system, and the rocket is based on hybrid propulsion incorporating a liquid oxidizer with a solid polybutadiene fuel. The launch vehicle for the system is a ground-launched four-stage vehicle that

George R. Whittinghill; Bevin C. McKinney

1992-01-01

299

An overview of the OmniTRACS - The first operational two-way mobile Ku-band satellite communications system  

NASA Astrophysics Data System (ADS)

A two-way mobile Ku-band satellite-based communications system is presented, which has a position reporting capability integrated into a mobile terminal, allowing automatic transmission of LORAN-C derived position information. The system and its service capabilities are described, including the mobile satellite terminal and network management facility. The possible applications of the system are outlined, including applications in transportation, vehicle location, public safety, and public utilities.

Jacobs, Irwin M.

1989-12-01

300

Space Station's biggest challenge - Servicing satellites in orbit  

Microsoft Academic Search

Attention is given to NASA's use of the prospective Space Station for the servicing of satellites in orbit, beginning with simple refueling tasks and culminating with the repair of sophisticated components. The Space Station will eventually perform all types of servicing on a variety of free-flying, reusable, unmanned platforms, or 'free flyers', which after being carried into low earth orbit

J. H. Brahney

1985-01-01

301

Hybrid Global Communication Architecture with Balloons and Satellites  

NASA Astrophysics Data System (ADS)

Global space communication systems have been developed now for more than three decades, based mainly on geostationary satellites or almost equivalent systems such as the Molnya orbit concepts. The last decade of the twentieth century has seen the emergence of satellite constellations in low or medium Earth orbit, in order to improve accessibility in terms of visibility at higher latitudes and limited size or power requirement for ground equipment. However such systems are complex to operate, there are still many situations where connection may remain difficult to achieve, and commercial benefits are still to be proven. A new concept, using a network combination of geostationary relay satellites and high altitude stratospheric platforms may well overcome the inconveniences of both geostationary systems and satellite constellations to improve greatly global communication in the future. The emergence of enabling technologies developed in Japan and in several other countries will soon make it possible to fly helium balloons in the upper layers of the atmosphere, at altitudes of 20 km or more. At such an altitude, well above the meteorological disturbances and the jet-streams, the stratosphere enjoys a regular wind at moderate speeds ranging between 10 m/s and 30 m/s, depending on latitude and also on season. It is possible for balloons powered by electric engines to fly non- stop upstream of the wind in order to remain stationary above a particular location. Large balloons, with sizes up to 300 m in length, would be able to carry sub-satellite communication payloads, as well as observation apparatus and scientific equipment. The range of visibility for easy both-way communication between the balloon and operators or customers on the ground could be as large as 200 km in radius. Most current studies consider a combination of solar cells and storage batteries to power the balloons, but microwave beam wireless power transportation from the ground could be a very attractive alternative. A fleet of stratospheric balloons could cover the communication needs of all the major economic centres around the Earth, at unit costs that would be only a fraction of the current satellite systems that could serve the same needs. It will be possible to interconnect all the balloons through a handful of geostationary relay satellites. Because the balloons will be in ever-clear atmosphere, without fear of rain or cloud attenuation, it will be possible to use very high frequencies in the range of 60 GHz to 100 GHz, or even laser link systems, between the geostationary satellites and the balloons. There are many developments that need to be made to achieve operational systems, some requiring extended study and testing, such as handling very large balloons in the lower parts of the atmosphere during launch, designing industry-rated energy beam systems, maintaining the balloons for continuous operation over years or decades. But at the beginning of the 21st century, it appears that all these challenges may be met to offer Mankind the most efficient global communication system so far.

Pignolet, G.; Celeste, A.; Erb, B.

2002-01-01

302

Study of a Satellite Communication System for Wideband Communications: Executive Summary.  

National Technical Information Service (NTIS)

Configurations of a 20/30 GHz satellite system providing wide band services over Europe in the 1990's were studied to identify payload technologies which have to be developed. A market study assessed potential demand for wide band services in Europe and d...

1983-01-01

303

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

Code of Federal Regulations, 2011 CFR

...2011-10-01 false Technical requirements for space stations in the Fixed-Satellite Service... § 25.210 Technical requirements for space stations in the Fixed-Satellite Service. (a) All space stations in the Fixed-Satellite...

2011-10-01

304

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

Code of Federal Regulations, 2012 CFR

...2012-10-01 false Technical requirements for space stations in the Fixed-Satellite Service... § 25.210 Technical requirements for space stations in the Fixed-Satellite Service. (a) All space stations in the Fixed-Satellite...

2012-10-01

305

47 CFR 80.333 - Stations in the maritime mobile-satellite service.  

Code of Federal Regulations, 2011 CFR

...false Stations in the maritime mobile-satellite service. 80.333 Section 80.333...333 Stations in the maritime mobile-satellite service. The provisions of...earth stations in the maritime mobile-satellite...

2011-10-01

306

47 CFR 80.333 - Stations in the maritime mobile-satellite service.  

Code of Federal Regulations, 2012 CFR

...false Stations in the maritime mobile-satellite service. 80.333 Section 80.333...333 Stations in the maritime mobile-satellite service. The provisions of...earth stations in the maritime mobile-satellite...

2012-10-01

307

EUTELTRACS: The European experience on mobile satellite services  

NASA Astrophysics Data System (ADS)

EUTELTRACS is Europe's first commercially operated Mobile Satellite Service. Under the overall network operation of EUTELSAT, the European Telecommunications Satellite Organization, EUTELTRACS provides an integrated message exchange and position reporting service. This paper describes the EUTELTRACS system architecture, the message exchange and the position reporting services, including the result of recent analysis of message delivery time and positioning accuracy. It also provides an overview of the commercial deployment, the regulatory situation for its operation within Europe and new applications outside its target market, the international road transportation.

Colcy, Jean-Noel; Steinhaeuser, Rafael

308

The prospects for domestic and international satellite communications 1980-2000  

NASA Astrophysics Data System (ADS)

Planned responses to a growing demand for increased domestic and international satellite telecommunications capacity are explored, noting that almost 100% of the current 156 transponders in orbit are in use. Eight satellites are in orbit, seven are under construction, and 16 are planned, with a trend evident toward higher capacity spacecraft for GEO. Service expansions will occur for data communication, telephony, videoconferencing, and TV, and projected requirements are given. A multibeam satellite for U.S. domestic use is described, and will comprise Shuttle launch and subsequent employment of C-, Ku-, and Ka-bands with adjacent beams on different wavelengths. Research by NASA and industry for developing full international coverage using a cellular approach and the INTELSAT system is outlined; equipment and cost savings due to increased onboard processing sophistication is shown to ease requirements for terrestrial hardware.

Stamminger, R.; Stein, J. A.

1981-12-01

309

Tele-X - A multipurpose communication satellite for the Nordic countries  

NASA Astrophysics Data System (ADS)

Tele-X, the satellite being developed with Norwegian, Swedish, and Finnish government funding by SSC and Aerospatiale to provide direct-broadcast TV, data transmissions, and video transmissions to the Scandinavian countries, is characterized. The three-axis-stabilized 1200-kg-orbit-weight satellite uses the platform, service module, propulsion system, antennas, solar array, and Ariane adapter developed for the TDF-1/TV-Sat spacecraft; the 170-kg communications payload includes three 27-MHz 230-W TWTA TV channels for 18-GHz uplink and 12-GHz downlink (providing 60-dBW EIRP to the entire coverage area) and one 40-MHz and one 86-MHz data/video channel (also with 230-W TWTAs) for bit rates as high as 140 Mbit/s. The industrial organization of the project is indicated, and diagrams, maps, drawings, and tables of the satellite parameters are provided.

Germain, J.

1984-09-01

310

A systems approach to the commercialization of space communications technology - The NASA/JPL Mobile Satellite Program  

NASA Astrophysics Data System (ADS)

This paper discusss the systems approach taken by NASA and the Jet Propulsion Laboratory in the commercialization of land-mobile satellite services (LMSS) in the United States. As the lead center for NASA's Mobile Satellite Program, JPL was involved in identifying and addressing many of the key barriers to commercialization of mobile satellite communications, including technical, economic, regulatory and institutional risks, or uncertainties. The systems engineering approach described here was used to mitigate these risks. The result was the development and implementation of the JPL Mobile Satellite Experiment Project. This Project included not only technology development, but also studies to support NASA in the definition of the regulatory, market, and investment environments within which LMSS would evolve and eventually operate, as well as initiatives to mitigate their associated commercialization risks. The end result of these government-led endeavors was the acceleration of the introduction of commercial mobile satellite services, both nationally and internationally.

Weber, William J., III; Gray, Valerie W.; Jackson, Byron; Steele, Laura C.

1991-10-01

311

Bispectrum modulation for jamming rejection on satellite communication channels  

NASA Astrophysics Data System (ADS)

The Global Grid communications environment is designed to provide a high-data-rate network that supports the full complement of DoD communications needs. Satellite links are an integral part of the Global Grid concept which extends the connectivity to individual mobile units and jointly operating forces at isolated locations. However, satellite channels are vulnerable to jamming, in particular when a high data rate is required. To overcome the jamming problem, the traditional approach is to design modulation techniques such that, on the average, the spectrum of the signal looks like the spectrum of a white noise process. This together with channel coding provides immunity against jamming. The main problem with this approach is that it requires a much larger spectrum than that of the data sequence; hence, the available spectrum on the link is used mostly for jamming protection and not for data communications. The traditional modulation techniques employed on satellite communication links are based on various properties of the second-order spectrum of the modulation wave form. In this study we have explored the utility and performance of a new family of modulation schemes that exploit the properties of the higher-order cumulant sequences and associated polyspectra of the waveform. In particular, we have investigated an approach in which the third-order polyspectrum, which is generally referred to as the bispectrum, is modulated. To determine the performance characteristics of this bispectral modulation scheme, we have considered two different detector structures, for which we have completed both theoretical and simulated performance analyses.

Barton, Richard J.

1995-05-01

312

Study on ISL network structure in LEO satellite communication systems  

NASA Astrophysics Data System (ADS)

Many parameters have to be taken into account in designing an LEO satellite constellation including transmission delay, service coverage, minimum elevation angle, and the effects of space radiation. We selected the 2 ? constellation for the NeLS ISL study to maintain continuous ISL connections, which is expressed by using a Walker notation of 120/10/1 with 55° of inclination. The satellite orbit parameters were examined under conditions where at least two satellites were always visible from the user terminal to enable satellite diversity. The optimum inclination angle for the 2 ? constellation was directly derived from the spherical triangle formed by three adjacent satellites. To evaluate the NeLS's ISL performance, the structure for ISL connections was simplified by using constellation parameters of 121/11/0 instead of 120/10/1. The ISL network had a bi-directional MSN structure with these parameters. The inter-orbital ISL, especially, achieved a ring network shaped like a figure-of-eight using n to n-1 connections. The bi-directional MSN topology of ISL connections is also discussed. A combination of constellation parameters P, S, and F were found to have simple relations in the n to n-1 connections of inter-orbital ISLs. Finally, optimum parameters for the NeLS constellation are discussed, and a candidate parameter ( T/P/F=132/11/-1, h=1100km, and I=57.92?) is proposed.

Suzuki, Ryutaro; Yasuda, Yasuhiko

2007-10-01

313

Telecommunications: Issues in Providing Cable and Satellite Television Services  

NASA Astrophysics Data System (ADS)

This report provides information on (1) whether the availability of cable modem Internet access service appears to be affecting the competitiveness of direct broadcast satellite (DBS) companies in the provision of video services, (2) whether cable prices and DBS penetration rates appear to be affected in areas where the DBS companies offer local broadcast channels, and (3) whether the two individual DBS companies are technologically capable of expanding local broadcast channel services into all 210 television markets in the United States.

2002-10-01

314

Evaluation of Diversity and Power Control Techniques for Satellite Communication Systems in Tropical and Equatorial Rain Climates  

Microsoft Academic Search

Satellite communication systems operating at frequencies above 10 GHz in tropical climates are subjected to many fade occurrences due to heavy rain. Service providers need to consider the use of appropriate forward error correction codes, the choice of modulations, diversity techniques, and the range of uplink\\/downlink power controls to use during severe rain fade periods in the overall design of

Qing Wei Pan; Jeremy E. Allnutt; Charles Tsui

2008-01-01

315

Space station automation study: satellite servicing. Volume II. Technical report  

SciTech Connect

This study was conducted by TRW over the six month time frame from early June through November 1984. Three major tasks were completed: Servicing Requirements (Satellite and Space Station Elements) and the Role of Automation; Assessment of Automation Technology; and Conceptual Design of Servicing Facilities on the Space Station. It was found that many servicing functions could benefit from automation support; that certain research and development activities on automation technologies for servicing should start as soon as possible; and some advanced automation developments for orbital servicing could be effectively applied to US industrial ground based operations. 42 refs., 49 figs., 20 tabs.

Meissinger, H.F.

1984-12-20

316

The Federal Communications Commission and the Communications Satellite Corporation: A Question of Ownership.  

ERIC Educational Resources Information Center

When NASA announced in 1960 that private enterprise would produce communication satellites, rather than the Federal government, several large corporations proposed a joint venture involving a group of international carriers and electronic manufacturers, while American Telephone and Telegraph requested sole ownership. At that time, the Federal…

Lee, William E.

317

Modulation and coding for satellite and space communications  

NASA Astrophysics Data System (ADS)

Several modulation and coding advances supported by NASA are summarized. To support long-constraint-length convolutional code, a VLSI maximum-likelihood decoder, utilizing parallel processing techniques, which is being developed to decode convolutional codes of constraint length 15 and a code rate as low as 1/6 is discussed. A VLSI high-speed 8-b Reed-Solomon decoder which is being developed for advanced tracking and data relay satellite (ATDRS) applications is discussed. A 300-Mb/s modem with continuous phase modulation (CPM) and codings which is being developed for ATDRS is discussed. Trellis-coded modulation (TCM) techniques are discussed for satellite-based mobile communication applications.

Yuen, Joseph H.; Simon, Marvin K.; Pollara, Fabrizio; Divsalar, Dariush; Miller, Warner H.; Morakis, James C.; Ryan, Carl R.

1990-07-01

318

Advancing the art of satellite communications - Foreign competition spurs NASA Satcom research  

NASA Astrophysics Data System (ADS)

Major advances in satellite communications technology in the US and Japan are detailed. Japan's Ka-band services aboard CS-2a and CS-2b, launched in 1973, are discussed, as well as plans for the ECS-2 and ACTS-E (Advanced Communications Technology Satellite) experimental projects. The ACTS-E would carry both a broadcasting payload operating at 27/22 GHz and a communication payload using the 50/40 GHz band. Japan's fourth generation CS-4, for start-up in the first half of the 1990's, is described as a 2-ton craft carrying 60-70 transponders, and providing capacity for up to 100,000 equivalent two-way voice channels via 10 or 20 scanning spotbeams. NASA's new programs are described as well, including the ACTS program, with a communications payload embodying signal-processing, message-routing, and traffic-management techniques, and the MSAT program, concentrating on narrow-band transmissions. Included are the technical description, operational parameters, and schematic layout of NASA's ACTS, and block diagrams of baseband processor for low burst rate communications switching on the ACTS.

Bulloch, C.

1985-01-01

319

Utilization of the Multiple Access Communications Satellite (Macsat) in support of tactical communications  

NASA Astrophysics Data System (ADS)

After a brief on-orbit checkout, the two Macsats launched into 90-deg, near-circular, 400-n. mi. altitude polar orbits on May 9, 1990 began to furnish operational communications support to USMC aircraft involved in Operations Desert Shield and Desert Storm. These operations of the Macsats furnished numerous lessons applicable to prospective design and deployment of small tactical-communications satellites. Macsats proved their ability to support quick-reaction requirements through reschedulings within 2-10 hrs. Their user communications terminal is portable, and easily relocated with changing requirements.

Steele, B.; McCormick, C.; Brandt, K.; Fornwalt, W.; Bonometti, R.

1992-03-01

320

77 FR 58579 - Certain Two-Way Global Satellite Communication Devices, System and Components Thereof...  

Federal Register 2010, 2011, 2012, 2013

...Certain Two-Way Global Satellite Communication...certain two-way global satellite communication...issue an exclusion order and cease and desist orders. ADDRESSES: The...Commission should contact the Office of the...certain two-way global satellite...

2012-09-21

321

Distributed media control tor multimedia communications services  

Microsoft Academic Search

Previous work in distributed feature composition architecture has shown that a modular, compositional architecture of feature logic can lead to successful management of feature interaction. It can also promote rapid deployment of new services and third party innovation in a communication network. ECLIPSE is an implementation of DFC that focuses on voice over IP (VoIP) and multimedia over IP. In

Eric Cheung; Pamela Zave

2002-01-01

322

The NHTSA emergency medical services communications program  

Microsoft Academic Search

The expansion of emergency medical services is limited by residual problems of inadequacy of communications systems developed using insufficient and inadequate VHF frequency channels. The promise of correcting these inadequacies by making available a block of UHF channels for use with a common frequency allocation structure is being diluted by short-sighted planning permitted by inadequacies in applicable FCC rules. There

C. J. Glass

1979-01-01

323

Service architectures and service creation for integrated broadband communications  

Microsoft Academic Search

RACE is a collaborative, pre-competitive R&D programme, partially funded by the European Union. The programme comprises a number of projects involving participants from all major European telecommunications sectors. The focus is IBC, a concept which encompasses broadband fixed and mobile networks, broadcasting and multimedia communication services. The goal is to further the development and deployment of IBC in Europe, eventually

Sebastiano Trigila; Alvin P. Mullery; Mário Campolargo; June Hunt

1995-01-01

324

Multicast Routing Algorithms and Failure Analyses for Low Earth Orbit Satellite Communication Networks.  

National Technical Information Service (NTIS)

In the rapidly changing environment of mobile communications, the importance of the mobile satellite (e,g,, low earth orbit satellites (LEOsats)) networks will increase due to their global visibility and connection. Multicasting is an effective communicat...

J. S. Lee

2002-01-01

325

DOD Use of Commercial Wideband Satellite Communications Systems: How Much is Needed, and How Do We Get It?  

NASA Astrophysics Data System (ADS)

Joint force commanders must have the right information at the right time in order to make the best decisions to conduct successful contingency operations in defense of U.S. national security interests. A key enabler to this end is sufficient wideband satellite communications connectivity DoD's (Department of Defense) organic wideband satellite communications capabilities are inadequate, so commercial services must be used to overcome the shortfall. The problem is to dedicate enough resources in the most efficient manner to meet this growing need, and time is of the essence, This paper capitalizes on the vast work already accomplished concerning what DoD needs to do to obtain the commercial wideband satellite communications it needs. DoD is procuring advanced satellite ground terminals capable of using commercial wideband satellites and is contracting to launch more of its own capabilities, but the gap is continuing to widen. This paper offers a solution of procuring 140 percent of DoD's projected wideband satellite communications from commercial sources, to ensure sufficient capacity is available to support contingency operations.

Hutchens, Robert E., III

2001-04-01

326

Performance limitations of free-space optical communication satellite networks due to vibrations-analog case  

Microsoft Academic Search

Free-space optical communication between satellites networked together can make possible high-speed communication between different places on earth. The use of optical radiation as a carrier between the satellites creates very narrow beam divergence angles. Due to the narrow-beam divergence angle and the large distance between the satellites, the pointing from one satellite to another is complicated. The complication is due

Shlomi Arnon; Norman S. Kopeika

1997-01-01

327

Autonomous robotic operations for on-orbit satellite servicing  

NASA Astrophysics Data System (ADS)

The Orbital Express Demonstration System (OEDS) flight test successfully demonstrated technologies required to autonomously service satellites on-orbit. The mission's integrated robotics solution, the Orbital Express Demonstration Manipulator System (OEDMS) developed by MDA, performed critical flight test operations. The OEDMS comprised a six-jointed robotic manipulator arm and its avionics, non-proprietary servicing and ORU (Orbital Replacement Unit) interfaces, a vision and arm control system for autonomous satellite capture, and a suite of Ground Segment and Flight Segment software allowing script generation and execution under supervised or full autonomy. The arm was mounted on ASTRO, the servicer spacecraft developed by Boeing. The NextSat, developed by Ball Aerospace, served as the client satellite. The OEDMS demonstrated two key goals of the OEDS flight test: autonomous free-flyer capture and berthing of a client satellite, and autonomous transfer of ORUs from servicer to client and back. The paper provides a description of the OEDMS and the key operations it performed.

Ogilvie, Andrew; Allport, Justin; Hannah, Michael; Lymer, John

2008-05-01

328

Red, White, and Blues: Library Services to a Satellite Campus  

ERIC Educational Resources Information Center

Over the last decade, an increasing number of academic institutions have built satellite campuses and developed online courses to meet the needs of distance learners. As these academic institutions have expanded, demand for library service has increased significantly. In an attempt to expand its course offerings to distance learners, Regent…

Lee, Marta

2004-01-01

329

Intelligent information dissemination services in hybrid satellite?wireless networks  

Microsoft Academic Search

The need for rapid deployment and user mobility suggest the use of a hybrid satellite-wireless network infrastructure for important situation awareness and emergency response applications. An Intelligent Information Dissemination Service (IIDS) has been developed to support the dissemination and maintenance of extended situation awareness throughout such a network information infrastructure in a seamless manner. One of the goals of IIDS

Eddie C. Shek; Son K. Dao; Yongguang Zhang; Darrel J. Van Buer; Giovanni Giuffrida

2000-01-01

330

Personal communications services: Improving theater deployable communications for the 21st century  

Microsoft Academic Search

Personal Communications Services (PCS) may be the key ingredient for vastly improved military communications capabilities at the turn of the century. The Federal Communications Commission (FCC) defines PCS as a family of mobile or portable radio communications services which could provide services to individuals and businesses and be integrated with a variety of competing networks ... the primary focus of

Ronald C. Cournoyer Jr.

1994-01-01

331

47 CFR 73.593 - Subsidiary communications services.  

Code of Federal Regulations, 2012 CFR

...Telecommunication 4 2012-10-01 2012-10-01 false Subsidiary communications services. 73.593 Section 73.593 ...Noncommercial Educational FM Broadcast Stations § 73.593 Subsidiary communications services. The licensee of a...

2012-10-01

332

Integration of mobile satellite service with advanced traffic management systems  

NASA Astrophysics Data System (ADS)

Mobile satellite communications systems are reviewed, and applications to the Intelligent Vehicle Highway System (IVHS) are described for the positioning and communications systems of the trucking industry. The advantages of the concept are set forth, and the components of mobile satellite system technologies are listed. Subscriber software and database access are discussed with respect to potential applications of the system including updating vehicle logs, translating driver messages, and checking vehicles. Computerized routing and vehicle tracking can be implemented with the system which would permit the optimization of routing in the trucking industry. The IVHS technologies contribute to four functional areas of traffic operations including traffic management, driver information, commercial vehicle operation, and advanced vehicle control systems.

Davis, Christopher L.

1991-04-01

333

Robotic servicing on Earth orbiting satellites  

NASA Astrophysics Data System (ADS)

An articulated calibration experiment (ACE) concept study was conducted by GSFC to prove the feasibility of instrument calibration by a resident robot on the EOS spacecraft. This study provided a basis for determining the most suitable robot design and operations concepts required to perform accurate instrument calibration on the EOS platform. During the study, the first-order dynamics of robot walking and docking motions as it moves about were evaluated to determine the accelerations and torques imparted into the spacecraft. The major perturbation to the spacecraft was the effect of robot motion and impact on the EOS platform attitude control system. If not carefully controlled, these levels could exceed the maximum allowable levels. As a result of the EOS/ACE feasibility study, a GSFC robotic ground development effort was established. This effort, as described on the paper, will identify the technology required to resolve issues associated with robot in-space servicing dynamics and its impact on spacecraft and designs. Of primary concern are those relating to robot contact loads, docking of robotic systems on space platforms, and basic motion and mobility.

Ollendorf, Stanford

1993-02-01

334

Scheduling algorithm for data relay satellite optical communication based on artificial intelligent optimization  

NASA Astrophysics Data System (ADS)

Optical satellite communication with the advantages of broadband, large capacity and low power consuming broke the bottleneck of the traditional microwave satellite communication. The formation of the Space-based Information System with the technology of high performance optical inter-satellite communication and the realization of global seamless coverage and mobile terminal accessing are the necessary trend of the development of optical satellite communication. Considering the resources, missions and restraints of Data Relay Satellite Optical Communication System, a model of optical communication resources scheduling is established and a scheduling algorithm based on artificial intelligent optimization is put forwarded. According to the multi-relay-satellite, multi-user-satellite, multi-optical-antenna and multi-mission with several priority weights, the resources are scheduled reasonable by the operation: "Ascertain Current Mission Scheduling Time" and "Refresh Latter Mission Time-Window". The priority weight is considered as the parameter of the fitness function and the scheduling project is optimized by the Genetic Algorithm. The simulation scenarios including 3 relay satellites with 6 optical antennas, 12 user satellites and 30 missions, the simulation result reveals that the algorithm obtain satisfactory results in both efficiency and performance and resources scheduling model and the optimization algorithm are suitable in multi-relay-satellite, multi-user-satellite, and multi-optical-antenna recourses scheduling problem.

Zhao, Wei-hu; Zhao, Jing; Zhao, Shang-hong; Li, Yong-jun; Wang, Xiang; Dong, Yi; Dong, Chen

2013-08-01

335

11-GHz fiber optic links for airborne satellite communications applications  

NASA Astrophysics Data System (ADS)

The first implementation of fiber optics at 11 GHz is reported in an experimental satellite communication EHF/SHF research terminal for airborne applications. A functional block diagram of the terminal is shown and discussed, and the fiber optical link is illustrated and described. SNR and bit-error rate (BER) were measured. The results demonstrate that system performance is not significantly degraded by insertion of the fiber optic link, which provides lightweight long-distance remoting that is not practical at high frequencies with coaxial cable or waveguides. The BER results demonstrate that these links can meet the low-noise, high-frequency, and flat frequency response required, and that they could enhance the flexibility and performance of SATCOM terminals for MILSTAR applications.

Gee, C. M.; Thurmond, G. D.; Newberg, I. L.; Yen, H. W.; Lafaw, D.

1988-04-01

336

Optical phase locked loop for transparent inter-satellite communications  

NASA Astrophysics Data System (ADS)

A novel type of optical phase locked loop (OPLL), optimized for homodyne inter-satellite communication, is presented. The loop employs a conventional 180? 3 dB optical hybrid and an AC-coupled balanced front end. No residual carrier transmission is required for phase locking. The loop accepts analog as well as digital data and various modulation formats. The only requirement to the transmitted user signal is a constant envelope. Phase error extraction occurs through applying a small sinusoidal local oscillator (LO) phase disturbance, while measuring its impact on the power of the baseband output signal. First experimental results indicate a receiver sensitivity of 36 photons/bit (-55.7 dBm) for a BER of 10 ^-9, when transmitting a PRBS-31 signal at a data rate of 400 Mbit/s. The system setup employs diode-pumped Nd:YAG lasers at a wavelength of 1.06 ?m.

Herzog, F.; Kudielka, K.; Erni, D.; Bächtold, W.

2005-05-01

337

Communications and radio determination system using two geostationary satellites. Part I: System and experiments  

NASA Astrophysics Data System (ADS)

We developed two types of hybrid terminals that can provide both satellite communication and position determination services in one system. One terminal uses the single channel per carrier (SCPC) technique and the other uses the spread spectrum (SS) technique. To evaluate the performance of the two systems, we carried out experiments in Japan and in the Pacific Ocean using two geostationary satellites, ETS-V (150 deg E) and Inmarsat (180 deg E). The ranging accuracy between the mobile terminals and the base station via the satellites was found to be about 200 m using the SCPC system and about 10 m using the SS system. The measured positioning accuracy was about 1 km in the SCPC system and about 600 m in the SS system when experiments were carried out near Japan. The experimental results show that the positioning errors were mainly caused by the orbital determination errors of the two satellites. Presented here are the configurations and features of the SCPC and SS terminals, the experimental system, and the experimental results.

Morikawa, Eihisa; Miura, Ryu; Matsumoto, Yasushi; Kimura, Kazuhiro; Arakaki, Yoshiya; Ohmori, Shingo; Wakana, Hiromitsu

1995-04-01

338

Progress toward direct broadcast satellite service in the United States of America  

NASA Astrophysics Data System (ADS)

There exist no significant technical or regulatory impediments to the commercial implementation of Direct Broadcast Satellite (DBS) service in the United States, although this service is handicapped by the lack of standard modulation and encryption formats. Problems confronting would-be DBS system operators at this early stage of the business are the fundamental ones like what types of programming will attract enough viewers to pay for the service; should the service be supported by subscription, commercial sponsorship, or some combination of the two; and how can the large start-up costs be shared or otherwise managed. The first three Federal Communications Commission (FCC) construction permit holders are each looking to 'narrowcasting' to the tremendous number of potential viewers across the United States, to accumulate a viable customer base for each specialized type of programming.

Clark, J. F.

1984-10-01

339

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

Federal Register 2010, 2011, 2012, 2013

...Proceeding; Certain Two-Way Global Satellite Communication...April 5, 2013, consent order issued in the above-captioned...FOR FURTHER INFORMATION CONTACT: Clint Gerdine, Esq...of certain two-way global satellite communication...investigation based on a consent order stipulation and...

2013-05-24

340

An up-link power control for demand assignment International Business Satellite Communications Network  

NASA Astrophysics Data System (ADS)

Up-link power control (UPC) is one of the essential technologies to provide efficient satellite communication systems operated at frequency bands above 10 GHz. A simple and cost-effective UPC scheme applicable to a demand assignment international business satellite communications system has been developed. This paper presents the UPC scheme, including the hardware implementation and its performance.

Nohara, Mitsuo; Takeuchi, Yoshio; Takahata, Fumio

341

Prototype adaptive optics system for ground-to-satellite laser communication  

Microsoft Academic Search

We have been studying a high-bit-rate satellite laser communications system between a ground station and a geostationary satellite, named high-speed optical feeder- link system. An adaptive optics (AO) is the best solution to compensate the degradation of the laser beam quality due to atmospheric turbulence and to realize such a high-bit-rate laser communication system.

Yutaka Hayano; Werner Klaus; Yoshinori Arimoto

1998-01-01

342

Lease Versus Buy Decision Making in the Navy's Satellite Communications Systems.  

National Technical Information Service (NTIS)

This thesis provides a general analysis of the United States (U.S.) Navy's lease versus buy decision model in the satellite communications systems. It also examines the Leased Satellite (LEASAT) and the Ultra High Frequency (UHF) Follow-on satellites. It ...

F. Engin

1989-01-01

343

A description of QUALCOMM Automatic Satellite Position Reporting (QASPR(R)) for mobile communications  

Microsoft Academic Search

Two satellite position reporting has been introduced into the OmniTRACS mobile satellite communication system. This system significantly improves position reporting reliability and accuracy while simplifying the terminal's hardware. The positioning technique uses the original OmniTRACS TDMA timing signal formats in the forward and return link directions plus an auxiliary, low power forward link signal through a second satellite to derive

William G. Ames

1990-01-01

344

Uplink Interference Adjustment for Mobile Satellite Service in Multibeam Environments  

Microsoft Academic Search

\\u000a In this paper, uplink interference, which can occur when frequencies are reused, and new measures are mainly discussed. First,\\u000a many different types of scenarios on uplink interference in Mobile Satellite Service in both normal and reverse mode are designed.\\u000a Then the simulator which analyzes uplink interference of a user link, among interferences that can occur when reuse frequencies\\u000a to make

Ill-Keun Rhee; Sang-Am Kim; Keewan Jung; Erchin Serpedin; Jong-Min Park; Young-Hun Lee

345

Communication satellite system for the Arab state countries 'ARABSAT'  

NASA Astrophysics Data System (ADS)

The operational and technical characteristics of the ARABSAT system, which will provide telecommunications services, sound, and television broadcasting to all Arab countries, are discussed. The system has three satellites, each with a seven-year lifetime nad reliability of 0.8 or more. These spacecraft are designed to be launched on either the Space Transporation System/Payload Assist module Delta or the ARIANE. The transmit and receive functions and the transponders are described. The telemetry, tracking, command, and ranging subystems functions are discussed, including the two control stations, the redundancy function, and the two command operation modes. Recommended characteristics for the earth stations, which are to be constructed by individual nations, are given.

Samarkandy, M. K.

346

Baseband performance degradation due to interference in the fixed-satellite service  

NASA Astrophysics Data System (ADS)

A set of receiver transfer characteristic (RTC) algorithms developed at the National Telecommunications and Information Administration (NTIA) for the analytical assessment of mutual interference effects in satellite communication services is described. The RTC algorithms convert the input carrier-to-interference power ratios (C/I) and modulation specifications of the desired (C) and interferer (I) signals into an output baseband performance degradation. The RTC algorithms also compute a C/I threshold margin for a given output baseband performance requirement. The modulation types and communication services include: companded single-sideband, amplitude-modulation, multichannel telephony; regular or companded, frequency-modulated, multichannel telephony; frequency-modulated analog television; digital coherent multiple-phase-shift keying; single-channel-per-carrier with digital coherent multiple-phase-shift keying; and single-channel-per-carrier with frequency-modulating analog voice.

Filippi, C.

1986-08-01

347

Status study on sustainability of satellite communication systems under hostile jamming environment  

Microsoft Academic Search

Globalization of commerce and interlinking of economics of all the countries in the world have changed the configurations of local\\/national\\/regional Communication links. They have now become truly global network centric. Satellite communication links offer flexible data transmission for ground, sea and airborne units. For military, these satellites have enhanced their capabilities with better co-ordination of command and control. Military satellites

G. Kumaraswamy Rao; R. Sree Hari Rao

2011-01-01

348

Laser satellite communication: precise estimation of the satellite position and synchronization and the stabilization of the beam on the receiving satellite  

Microsoft Academic Search

This paper analyses a number of systems and control issues associated with the design of a low orbit communications satellite network. This paper discusses the adaptation of ISDN ATM protocols to the constraints inherent with laser communications. The main proposed change is to replace the link-by-link off band routing by in band arrow routing. The first field is coded using

Lee Young Ju; Tomes Christian

2000-01-01

349

In-orbit measurements of spacecraft microvibrations for satellite laser communication links  

Microsoft Academic Search

Angular microvibrations of platform jitter on the optical inter-orbit communications engineering test satellite are measured in space during ground-to-satellite laser communication links. The microaccelerations are measured by the onboard accelerometers at a sampling rate of 2048 Hz. The angular microvibrations are estimated from the measured microaccelerations using the tracking characteristics of the laser communications terminal and the conversion factor on

Morio Toyoshima; Yoshihisa Takayama; Hiroo Kunimori; Takashi Jono; Shiro Yamakawa

2010-01-01

350

Completion of Optical Inter-Orbit Communications Engineering Test Satellite (OICETS)  

Microsoft Academic Search

National Space Development Agency of Japan (NASDA) has developed the Optical Inter-orbit Communications Engineering Test Satellite (OICETS) since 1993 in order to perform the optical inter-satellite communication experiment with ARTEMIS developed by European Space Agency (ESA). The system proto-fright test was completed in January 2002 and OICETS is ready for launch. OICETS has the free space laser communication equipment (so

K. Nakagawa; T. Yamawaki; M. Toyoshima; K. Arai

2002-01-01

351

The satellite climate monitoring programme of the German Meteorological Service  

NASA Astrophysics Data System (ADS)

The German Meteorological Service (DWD) is host of the Satellite Application Facility on Climate Monitoring (CM-SAF) of EUMETSAT. The CM-SAF with its international partners will provide climate data (daily and monthly means, monthly mean diurnal cycles) based on the satellite systems MSG (Meteosat Second Generation, the first MSG satellite was launched in fall 2002) and the polar orbiting satellites NOAA and EPS (the latter one is the EUMETSAT Polar Satellite System, the first satellite named METOP-1 is planned to be launched in 2005; the NOAA and METOP satellites will form the Initial Joint Polar Satellite System). The parameters to be generated by the CM-SAF are cloud parameters, components of the radiation budget at the earth’s surface and at the top of the atmosphere, ocean wind stress and water vapour in the atmosphere. The data will cover in the initial phase an area of Europe and the North Atlantic, later the area is planned to be extended to the polar regions and the whole MSG disc. The purpose of the CM-SAF is to generate, with long-term commitments on a fully operational basis, homogeneous and consistent products in high quality, which are suitable for assessments of the status of the (regional) climate system. Together with data from the Global Precipitation Climatology Centre (GPCC), which is also operated by the DWD, the CM-SAF products are suitable for monitoring components of the energy and water cycle. To establish a really powerful climate monitoring system, the German Meteorological Service additionally set up a national satellite climatology project called SAT-KLIM. This project uses the CM-SAF products for climate monitoring, but also other satellite climate data, ground based in situ and remote observations as well as model output. In SAT-KLIM, climate monitoring products will be derived from the different data sources and merged to one final high quality product. While CM-SAF can only consider present and future data, SAT-KLIM uses additional data of the past (with satellite data starting in the mid-eighties) to enable the monitoring of long-term climate variability. Further climate elements are also considered in SAT-KLIM, e.g. fog frequency and heat fluxes at the earth’s surface. The final aim of SAT-KLIM is the monitoring of all components of the energy balance at the earth’s surface and in the atmosphere. With such a concept it is not only possible to show, but also to explain and quantify climate changes on a physical basis by changes of regional energy balance components. CM-SAF and SAT-KLIM will start to become operational in 2004. This means that, starting next year, the first climate monitoring products will be released to the public via the Web on a regular (monthly) basis. The first climate monitoring approach in SAT-KLIM will be a very simple one: data of the current month will be compared to a long-term mean of a reference period. Later on, other evaluations (trends, statistical measures) will be added. The fully operational phase will be reached in 2007. Both projects are very challenging tasks since all the peculiarities of the different data sets have to be considered. Validation of all the data sets against each other is a very important aspect of CM-SAF as well as of SAT-KLIM. In this presentation, the concept of the two projects is explained and first demonstration products (climate maps, diagrams and validation results) are shown. The advantages, but also the problems of such a climate monitoring programme are discussed.

Bissolli, P.; Nitsche, H.; Wollenweber, G.; Benesch, W.; Müller-Westermeier, G.; Rosenow, W.

2003-04-01

352

The use of satellites in non-geostationary orbits for unloading geostationary communication satellite traffic peaks. Volume 1: Executive summary  

NASA Astrophysics Data System (ADS)

The overall objective of this program was to assess the application, economic benefits, and technology and system implications of satellites in non-geostationary (non-GEO) orbits for off-loading peak traffic from GEO communications satellites. The study was organized into four technical tasks which are described in turn. They are: (1) concepts development; (2) system definition; (3) economic comparisons; and (4) technology requirements definition. Each of these tasks is defined in detail and the results of each are given.

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

1987-05-01

353

Development status of the Communications and Broadcasting Engineering Test Satellite (COMETS)  

NASA Astrophysics Data System (ADS)

COMETS (Communications and Broadcasting Engineering Test Satellite) is the research and development purpose satellite in the area of satellite communications and broadcasting technologies, to be launched in 1997 by H-2 launch vehicle. The main mission is to experimentally demonstrate and evaluate the technologies on inter-orbit communications, advanced satellite broadcasting on Ka-band and advanced mobile satellite communications on Ka-band and millimeter-wave band. The development of COMETS has been started on March 1991 as the preliminary design phase, and the preliminary design reviews of the subsystems and systems of COMETS had been held between June 1992 to April 1993, in which the feasibility of COMETS system was confirmed. This paper presents the outline of S/C (spacecraft) mission, system configuration, S/C operation plan and development plan of COMETS based on the results of the preliminary design.

Ozawa, Keisuke; Oshida, Kazuhiko; Aoyama, Junichi; Sato, Naoki; Kawaguchi, Masayoshi; Oishi, Katsumi; Ikeda, Mizuho

1993-08-01

354

New approach to detector array receiver performance analysis for laser satellite communication  

Microsoft Academic Search

Laser satellite communication is one of the most promising methods of communication outside the earth's atmosphere. In the continuing quest to optimize atmospheric optical wireless communication, arrays of photodetectors are replacing solitary photodetectors in receivers, affording the advantages of the small fast photodiode while effectively increasing the receiver aperture. Thus, power dispersed by atmospheric turbulence and scattering may be collected

Eyal Kayton; Daniel M. Marom; Shlomi Arnon

2002-01-01

355

Inter-satellite ranging and inter-satellite communication links for enhancing GNSS satellite broadcast navigation data  

NASA Astrophysics Data System (ADS)

Recently the European Space Agency (ESA) has initiated a number of exploratory Projects, within the General Studies Programme (GSP), to analyze what potential improvements on a GNSS system navigation determination and dissemination performance could be brought by introducing inter-satellite ranging & inter-satellite communication-links. The key improvements targeted by these Projects are the enhancement of the orbit and clock prediction accuracy and the reduction of the dependency from ground infrastructure. Both projects adopted the Galileo system architecture as the initial working point.The first exploratory Project, which was labelled as GNSS+ (Amarillo and Gerner, 2007; Amarillo et al., 2008), indicated the practical difficulty to implement these new on-board functionalities except at the price of a visible increase of the payload mass and power (e.g. relative to mass and power of the Galileo IOV navigation payload) (Sánchez and Pulido, 2008); it allowed to define a preliminary system architecture, and it also allowed to identify the technological problems that in practise would likely be encountered.A second exploratory Project, which was labelled as ADVISE, continued the research, targeting a visible simplification of the GNSS+ architecture and an overall consolidation of the design of the most demanding constituents from technology perspective.This article describes the results of the GNSS+ Project as well as the improvements proposed in the frame of the ADVISE Project. As result of the ADVISE Project it has been possible to low very visibly the payload maximum RF power, and to keep the orbit and clock estimation accuracy, which was already on the few cm level.

Fernández, Francisco Amarillo

2011-03-01

356

Mobile satellite services: A survey of business needs  

NASA Astrophysics Data System (ADS)

Conceptualizing and understanding the international business traveler's communication requirements by the use of a survey and selection of a mobile satellite system that satisfies those requirements are discussed. Chapter 5 incorporates an in depth analysis of the respondent's answers to survey questions and graphing them with frequency distribution histograms. Chapter 6 concludes with a selection of the most likely MSS manufacturer who appears to satisfy those communication requirements discovered in the previous chapter. Following a general-introduction in Chapter 1, the current climate of mobile satellite system (MSS) providers is discussed in Chapter 2. Chapter 3 assesses the implication of launch vehicles as it pertains to the political, technical, and financial aspects of MSS manufacturers and users. Special attention is provided, when possible, between the political environment and its relationship with forefront technology. In chapter 4, the procedure that was used to create the survey and its research methodology is shown. Graphs and charts are used, where appropriate, for the purpose of clarity and readability.

Hainzer, Eric M.

357

Characteristics of scale models of large deployable mesh reflector antenna for mobile communications satellites  

NASA Astrophysics Data System (ADS)

In the land mobile satellite system (LMSS) using a geostationary platform (GPF), a 30 m diameter satellite antenna is desirable for small portable terminal communications. SCR has adopted two deployment types of antenna structure, the Hexa-Link Truss reflector and the Tetra-Triagonal Prism Truss (TETRUS) reflector, and has developed scale models of them. Both of them represent important aspects of large satellite antenna technology. This paper describes the SCR outline of a land mobile satellite communications system and the experimental results of the scale models. This research establishes the basic technical information necessary for the development of a 30 m diameter antenna and a conceptual GPF design.

Akaishi, Akira; Orikasa, Teruaki; Kashiki, Kanshiro; Okamoto, Teruki; Otsu, Yuichi; Satoh, Hideo

1993-10-01

358

Characteristics of scale models of large deployable mesh reflector antennas for mobile communications satellites  

NASA Astrophysics Data System (ADS)

In the land mobile satellite system (LMSS) using a geostationary platform (GPF), a 30 m diameter satellite antenna is desirable for small portable terminal communications. SCR has adopted two deployment types of antenna structure, the Hexa-Link Truss reflector and the Tetra-Triagonal Prism Truss (TETRUS) reflector, and has developed scale models of them. Both of them represent important aspects of large satellite antenna technology. This paper describes the SCR outline of a land mobile satellite communications system and the experimental results of the scale models. This research establishes the basic technical information necessary for the development of a 30 m diameter antenna and a conceptual GPF design.

Akaishi, Akira; Orikasa, Teruaki; Kashiki, Kanshiro; Okamoto, Teruki; Otsu, Yuichi; Satoh, Hideo

359

Social Media as Means for Company Communication and Service Design  

Microsoft Academic Search

\\u000a Service development in companies can have a new form when using social media as a communication interface. This communication\\u000a can occur between company and its customers, but also the company’s internal communication using social media services can\\u000a prove beneficial. In this paper, we review and analyze the use of social media as a means for company communication in general\\u000a and

Elina Annanperä; Jouni Markkula

2010-01-01

360

International Conference on Satellite Systems for Mobile Communications and Navigation, 4th, London, England, Oct. 17-19, 1988, Proceedings  

NASA Astrophysics Data System (ADS)

Attention is given to the following topics: antennas and propagation, systems for communication, systems for land mobile communications, systems for aeronautical communications, and system economics, operation, and traffic. Particular papers are presented on tracking receiver design for the electronic beam squint tracking system in the maritime mobile environment, network signalling system design considerations in a multiservice mobile satellite communication systems, Inmarsat's aeronautical satellite communication system, and proposed systems configurations for a satellite-based ISDN.

361

The changing role of satellites in AT&T's communication network  

NASA Astrophysics Data System (ADS)

The Bell System's COMSTAR Domestic Satellite System and its use in providing Message Telephone and Private Line Services is briefly discussed. Also decribed is the TELSTAR 3 satellites scheduled for initial launch in 1983 and how the use of satellites by AT&T-Long Lines is changing. Techniques being explored to increase satellite capacity are also covered - both for voice and for television signals.

Latter, R. F.

362

The role of direct broadcasting satellites in the integrated communications environment  

NASA Astrophysics Data System (ADS)

The global integration of information sources, telecommunication systems, and user terminals into a computer-controlled distributed communication network, known as the Integrated Services Digital Network (ISDN), will markedly affect the role of direct broadcasting satellites (DBS). DBS facilities will be increasingly used for the dissemination of non-video materials and will become a dominant means of electronic publishing. These facilities will also be used to selectively address information to dynamically definable classes of users, thus altering the very concept and definition of broadcasting. Finally, DBS will transform into multipoint distribution systems emanating from the ISDN. It is pointed out that although some of these developments wil not fully emerge for one or two decades, consideration should be given to the impact of the ISDN on society and its legal systems.

Rutkowski, A. M.

363

76 FR 49364 - Fixed and Mobile Services in the Mobile Satellite Service Bands at 1525-1559 MHz and 1626.5-1660...  

Federal Register 2010, 2011, 2012, 2013

...Fixed and Mobile Services in the Mobile Satellite Service Bands at 1525-1559 MHz and...Fixed and Mobile Services in the Mobile Satellite Service Bands at 1525-1559 MHz and...Fixed and Mobile Services in the Mobile Satellite Service Bands at 1525-1559 MHz...

2011-08-10

364

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

Code of Federal Regulations, 2010 CFR

...eligibility for mobile-satellite stations. 80... FEDERAL COMMUNICATIONS COMMISSION...SERVICES STATIONS IN THE MARITIME...Installations Mobile-Satellite...maritime mobile-satellite... (a) A station license for...nonprofit radio communication...

2010-10-01

365

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

Code of Federal Regulations, 2010 CFR

...eligibility for mobile-satellite stations. 80... FEDERAL COMMUNICATIONS COMMISSION...SERVICES STATIONS IN THE MARITIME...Installations Mobile-Satellite...maritime mobile-satellite... (a) A station license for...nonprofit radio communication...

2009-10-01

366

Coding for frequency hopped spread spectrum satellite communications  

NASA Astrophysics Data System (ADS)

Work aimed at improving the jamming resistance of satellite communications is reviewed. The performance of Reed-Solomon (RS) error correcting codes with slow frequency hopped (SFH) differential phase shift keying (DPSK) signalling is analyzed and evaluated under worst case partial band noise and worst case multitone jamming. A representative set of performance curves is shown. Recommendation on the choice of RS code parameters is given. Two in-hop jamming cancellation schemes for SFH/DPSK systems are proposed. One scheme is based on balanced coding; the other one uses notch filter to cancel jamming tone. The performance of both schemes is illustrated. It is shown that both schemes can work well under certain conditions. Basic principles and techniques for designing interleavers are presented. Block, convolution, and the more recent helical interleavers are considered. The trade-off between diversity and coding for spread spectrum systems, where a low code rate is anticipated, is discussed. An error correction scheme is presented for an M-ary symmetric channel (MSC) characterized by a large error probability (Pe). The value of Pe can be near, but smaller than 1-1/M, for which the channel capacity is zero. Such a large Pe may occur, for example, in a jamming environment. Monte-Carlo simulation results are presented. For the binary symmetric channel (BSC), it is shown that the overall code rate is larger than 0.6 R sub 0, where R sub 0 is the cutoff rate of the channel. For BSC and a large diversity order (m), a method is presented for BER (bit error rate) approximation on the central limit theorem.

Bhargava, Vijay K.; Wang, Qiang; Blake, Ian F.; Li, Gang; Gulliver, T. Aaron; Dravnieks, Olaf

1990-04-01

367

Satellite broadcasting in Europe  

NASA Astrophysics Data System (ADS)

Three main communications services are recognized by the International Telecommunications Union: the Fixed Service, the Mobile Service and the Broadcasting Service. In Europe, EUTELSAT has just begun to exploit the first ECS satellite. The ESA-launched satellite was originally designed to provide an international public telecommunication service, however, the satellite will be used now almost exclusively for TV program distribution, while a second ECS satellite will be used for telephony. Despite plans for the launch of a third, countries in Europe are looking to other organizations such as INTELSAT for greater satellite capacity. Other organizations include Unisat, DFS/Copernicus, GDL, and Videosat. Both satellite and cable networks will increase the program-viewing audience, thus encouraging plans for a pan-European television service intended for an international audience. Although the combination of cable networks and distribution satellites looks promising, high-power broadcasting satellites will play an important role because of flexibility and additional program distribution.

Bartholome, P.

1984-05-01

368

Telemetry and telecommand requirements for future synchronous orbit communications satellites  

Microsoft Academic Search

Requirements on telemetry and command are discussed from the satellite operations point of view. Requirements that lead to good visibility and control of the various satellite functions and enable the monitoring and control of the satellites to be computer-controlled are presented. Autonomous functions (on-board vs on-ground) are discussed, as are pros and cons on fixed and reconfigurable telemetry formats. The

Erland Magnusson

1989-01-01

369

Development of Five (Washington, Alaska, Montana, Idaho (WAMI)) Educational Experiments for the Communications Technology Satellite.  

National Technical Information Service (NTIS)

The launching of communications satellites by the National Aeronautics and Space Administration in 1974 and 1976 provided administrators of the Washington, Alaska, Montana, and Idaho (WAMI) program with an opportunity to assess the potential of this techn...

M. Johnson

1977-01-01

370

IpexT: Integrated Planning and Execution for Military Satellite Tele-Communications.  

National Technical Information Service (NTIS)

The next generation of military communications satellites may be designed as a fast packet-switched constellation of spacecraft able to withstand substantial bandwidth capacity fluctuation in the face of dynamic resource utilization and rapid environmenta...

C. Plaunt K. Rajan

2004-01-01

371

Millimeter Wave Propagation Modeling of Inhomogeneous Rain Media for Satellite Communications Systems.  

National Technical Information Service (NTIS)

A theoretical propagation model that represents the scattering properties of an inhomogeneous rain often found on a satellite communications link is presented. The model includes the scattering effects of an arbitrary distribution of particle type (rain o...

R. R. Persinger W. L. Stutzman

1978-01-01

372

Communication and Control in the Canadian North: The Role of Interactive Satellites.  

National Technical Information Service (NTIS)

In 1972 the Canadian government launched its first domestic communications satellite, Anik A, which relays direct broadcast television and telephone messages to northern communities. The impact of television on Inuit life has raised issues and concerns pe...

G. G. Valaskakis

1981-01-01

373

Military Satellite Communications Decision Support System Requirements Analysis and User Interface Design.  

National Technical Information Service (NTIS)

This research analyzed and decomposed U. S. Space Command missions to determine the requirements of a Military Satellite Communications Decision Support System (MDSS). Alternative functional architectures for an MDSS were evaluated and a geographical user...

H. A. Henry

1993-01-01

374

Comparison Between Low Circular and Elliptical Inclined Orbits for Small Satellites Communication Applications.  

National Technical Information Service (NTIS)

Some results of a system study concerning the performance of large constellations of small satellites in low circular and inclined elliptical orbits for real time communications are presented. Performances are evaluated in terms of visibility and mutual c...

G. Perrotta

1991-01-01

375

Economic effect of satellite communications based on the Great East Japan Earthquake  

NASA Astrophysics Data System (ADS)

On 11 March 2011, an undersea earthquake of magnitude 9.0, the largest ever recorded in Japan, occurred off the Oshika Peninsula on the Pacific coast of the Tohoku region. The hypocentral region extended for 500 km in the north-south direction from Iwate Prefecture to Ibaraki Prefecture, and for 200 km in east-west direction. The earthquake generated a tsunami with a height of more than 10 m and a run-up height of up to 40.0 m in certain places, which inflicted devastating damage on the coastal areas of the Tohoku and Kanto regions. In addition to the tsunami, the earthquake caused shaking, liquefaction, subsidence, and the collapse of dams, causing major damage to vast areas in the Tohoku and Kanto regions and disrupting various types of infrastructure, including communication. In light of this unprecedented damage, satellite communications were important from various perspectives while terrestrial communications systems were damaged, and an objective evaluation of the role played by satellite communications is relevant to its future installation, adoption and use as a standalone or backup system. Furthermore, satellite communications can help reduce the extent of damage, particularly damage to communications systems, inflicted by strong earthquakes in the future. Accordingly, we report a preliminary quantitative evaluation of the role of satellite communications in the Great East Japan Earthquake, of the role of satellite communications if it becomes widespread, and of its expected role in future large-scale earthquakes in terms of the economic effect converted into cost.

Toyoshima, Morio; Takahashi, Takashi; Miura, Amane; Fujino, Yoshiyuki; Akioka, Maki

2013-10-01

376

On communication and coordination issues of Semantic Web Services  

Microsoft Academic Search

Semantic Web services have been envisioned in the form of different conceptual models like OWL-S, WSMO and WSDL-S. Web services execution environment (WSMX) is our reference implementation for semantic Web service conceptual model, WSMO. In this paper, we have investigated the communication problems that semantic Web services systems are facing. We have proposed how to overcome these problems by using

M. Omair Shafiq; Michal Zaremba; Dieter Fensel

2007-01-01

377

Performance of MPSK and 16QAM in the satellite communication environment  

Microsoft Academic Search

This paper presents computer simulation results on the performance of quadrature phase shift keying (QPSK), 8-ary phase shift keying (8PSK), and 16 quadrature amplitude modulation (16QAM) schemes in a satellite communication environment employing frequency division multiple accessing (FDMA). The end-to-end communication system, which includes the modulator, klystron amplifier, satellite transponder, carrier and timing recovery loops, and the channel filters, is

J. C. Chen; L. Cooper; D. Taggart; N. S. Wagner; R. Kumar; T. Nguyen; J. Yoh; G. Leon; G. W. Goo

2004-01-01

378

Fiber Bragg grating as optical filter in laser inter-satellites communication  

Microsoft Academic Search

This paper proposes a method of using fiber Bragg grating as optical filter in laser inter-satellites communication system. Effects of Doppler shift to SNR and band requirement of optical filter are researched in this paper. Given the wavelength is 1550nm, strong fiber and Blackman windows function are used in designing fiber grating to satisfy the need of the inter-satellites communication

Zou Xia; Wen Chuanhua; Li Yuquan; Zhou Li

2007-01-01

379

Maritime satellite communications equipment of KDD - Experimental system \\/MARSK-X  

Microsoft Academic Search

The paper describes the system configuration, modulation techniques, and access control method of an experimental maritime satellite communications system called MARSK-X with a view toward evaluating technical problems and establishing the optimum design technique for a future maritime satellite communications system. The MARSK-X system consists of a shipboard below-deck terminal, a shore station equipment, and an IF interface for interconnection.

T. Satoh; Y. Hirata; T. Takahashi

1976-01-01

380

Polymeric waveguide hologram based 4-channel coarse WDM for satellite optical communications  

Microsoft Academic Search

In this paper, a coarse photopolymer grating-based WDM device is proposed and developed to work for a simple point-to-point data transfer between two satellites. The four-channel CWDM device reported herein provides two data streams at 0.83 ?m and 1.55 ?m, an inter-satellite tracking channel at 1.06 ?m, and an intra-satellite communication channel at 1.34 ?m. This device works properly in

Lanlan Gu; Feng Zhao; Zhong Shi; Jian Liu; Ray T Chen

2004-01-01

381

Requirements for a mobile communications satellite system. Part 3: Large space structures measurements study  

Microsoft Academic Search

This study report defines a set of tests and measurements required to characterize the performance of a Large Space System (LSS), and to scale this data to other LSS satellites. Requirements from the Mobile Communication Satellite (MSAT) configurations derived in the parent study were used. MSAT utilizes a large, mesh deployable antenna, and encompasses a significant range of LSS technology

W. Akle

1983-01-01

382

Field test results on a digital transmission system for global maritime satellite communications  

Microsoft Academic Search

A field experiment of a digital shipborne earth station system was successfully performed from April to July 1984, using the shipborne Indian Ocean satellite (Intelsat V satellite with maritime communication subsystem). This paper outlines the experimental setups and presents the test results. The link parameters of the designed system are also discussed based on the obtained data. The test results

K. Kashiki; H. Okinaka; Y. Yasuda; T. Shiokawa; Y. Hirata

1985-01-01

383

Modeling and simulation of an orbit controller for a communication satellite  

Microsoft Academic Search

It is of critical importance to control the altitude of a satellite especially one used for worldwide communications in a geo-stationary orbit. The objective of this work is to evolve a design based on modeling and simulation of an orbit controller for a satellite orbiting into a circular orbit. This involves a good understanding of the system dynamics. Once a

Muhammad Afzaal Malik; Ghazanfar Abbas Zaidi; Iyaz Aziz; Shahab Khushnood

2001-01-01

384

Characteristics of scale models of large deployable mesh reflector antenna for mobile communications satellites  

Microsoft Academic Search

In the land mobile satellite system (LMSS) using a geostationary platform (GPF), a 30 m diameter satellite antenna is desirable for small portable terminal communications. SCR has adopted two deployment types of antenna structure, the Hexa-Link Truss reflector and the Tetra-Triagonal Prism Truss (TETRUS) reflector, and has developed scale models of them. Both of them represent important aspects of large

Akira Akaishi; Teruaki Orikasa; Kanshiro Kashiki; Teruki Okamoto; Yuichi Otsu; Hideo Satoh

1993-01-01

385

Characteristics of scale models of large deployable mesh reflector antennas for mobile communications satellites  

Microsoft Academic Search

In the land mobile satellite system (LMSS) using a geostationary platform (GPF), a 30 m diameter satellite antenna is desirable for small portable terminal communications. SCR has adopted two deployment types of antenna structure, the Hexa-Link Truss reflector and the Tetra-Triagonal Prism Truss (TETRUS) reflector, and has developed scale models of them. Both of them represent important aspects of large

Akira Akaishi; Teruaki Orikasa; Kanshiro Kashiki; Teruki Okamoto; Yuichi Otsu; Hideo Satoh

1993-01-01

386

The land mobile satellite communication channel-recording, statistics, and channel model  

Microsoft Academic Search

The communication channel between the MARECS satellite at 26 deg W and a cruising van was measured and recorded in European areas exhibiting satellite elevations from 13 to 43 deg. Different environments and mobile antennas were tested. Results of an extensive statistical evaluation include spectra of the fading amplitude, probability density, and distribution of the received signal power as well

Erich Lutz; Daniel Cygan; Michael Dippold; Frank Dolainsky; Wolfgang Papke

1991-01-01

387

Analysis of System Parameters for LEO\\/ICO-Satellite Communication Networks  

Microsoft Academic Search

Currently many efforts are undertaken to develop and install communication networks based on low Earth orbit (LEO) and intermediate circular orbit (ICO) satellites. However, many problems are to be solved before the final operation of such networks. This paper deals with basic design problems of LEO\\/ICO-based networks. The topology of the satellite network is considered and estimates for the number

Markus Werner; Axel Jahn; Erich Lutz; Axel Böttcher

1995-01-01

388

Effects of Electrostatic Discharge Phenomena on Telesat's Domestic Communications Satellites,  

National Technical Information Service (NTIS)

With the launch of Anik A1 in November, 1972, Telesat Canada became the first owner and operator of a geosynchronous domestic satellite. The company owns a total of nine satellites, of which six are still operational. Also Telesat is unique in that it is ...

P. N. Wadham

1987-01-01

389

Technical and economic feasibility of telerobotic on-orbit satellite servicing  

Microsoft Academic Search

The aim of this research is to devise an improved method for evaluating the technical and economic feasibility of telerobotic on-orbit satellite servicing scenarios. Past, present, and future telerobotic on-orbit servicing systems and their key capabilities are examined. Previous technical and economic analyses of satellite servicing are reviewed and evaluated. The standard method employed by previous feasibility studies is extended,

Brook Rowland Sullivan

2005-01-01

390

Small satellites with micro-propulsion for communications with the Lunar South Pole Aitkens Basin  

NASA Astrophysics Data System (ADS)

A lunar sample return mission to the Lunar South-Pole Aitkens Basin (LSPAB) has been highlighted as a high priority objective of the most recent (2011) Decadal Survey for Planetary Science, by the National Research Council. This class of mission, however, faces a dramatic communications limitation, due to the lack of a frequent, or continuous, line-of-sight communications path to Earth-based ground stations. Brunner and others have proposed a communications system utilizing Low Lunar Polar Orbits (LLPO) and Lunar Halo orbits for this purpose. Ely and others have outlined proposals for using several communication satellites to form a relay network using LLPO, taking into account the Lunar masscon's that would perturb such orbits. However, any relay network of communication satellites would still have to connect back to a suitable Earth-based ground station (Near Earth Network, or otherwise), or a tracking and data relaying satellite (e.g., TDRS).

Haque, Samudra E.; Straub, Jeremy; Whalen, David

391

MICS transceivers: regulatory standards and applications [medical implant communications service  

Microsoft Academic Search

The medical implant communications service (MICS) is an ultra-low power, unlicensed, mobile radio service for transmitting data in support of diagnostic or therapeutic functions associated with implanted medical devices. The US Federal Communications Commission (FCC) allocated the 402-405 MHz frequency band for MICS operations on a shared, secondary basis in 1999. Although it is a fairly new standard, its usage

Huseyin S. Savci; Ahmet Sula; Zheng Wang; Numan S. Dogan; Ercument Arvas

2005-01-01

392

Do future commercial broadband communication satellites really need laser-communication intersatellite links (ISLs)?  

NASA Astrophysics Data System (ADS)

Large commercial satellite programs requiring ISLs are growing in number and maturing. An important segment of the commercial satellite market, and its ISL needs, is discussed in the paper. ISL value will increase as long-haul terrestrial backbones become increasingly congested. Providing interregional and intercontinental connectivity via ISL presents far lower cost and fewer problems than relying on terrestrial fiber-optic networks. To demonstrate this, a new metric is proposed which allows 'apples-to- apples' cost/performance comparisons between laser communications in GEO, LEO, and terrestrial fiber-optics. ISL requirements in to the next decade are predicted >= 50-100 Gb/s full duplex. Many attitudinal changes must be embraced among those who choose to focus on this new commercial business. Foremost among these is a preponderance to delivering fully acceptable hardware fast and at low cost, as opposed to merely designing such. Considerable attention must be given business considerations foreign to professionals who have spent time in the government or government contracting sectors. Successful ISL customers will come to recognize that ISLs are not commodity products. Failure to embrace these attitudes will nonetheless constitute decision to which the commercial market, and particularly the financial market, will appropriately respond.

Freidell, James E.

1997-05-01

393

The role of communication systems in emergency medical services  

Microsoft Academic Search

The important role that land mobile communication systems play in the effective operation of an emergency medical services (EMS) system is discussed. The need for EMS systems, classification of types of communication subsystems, FCC Rules and Regulations for EMS, what to do before designing communication systems, and examples of several systems are given.

1976-01-01

394

Communication satellites in the geostationary orbit (2nd revised and enlarged edition)  

NASA Astrophysics Data System (ADS)

Regulatory, policy, and technical considerations pertaining to communications satellites in geostationary orbit (GSO) are addressed, and methods of dealing with the problem of interference that such satellites encounter are considered. An overview and historical perspective on GSO is given, and communication satellite sharing of the GSO is discussed. International and domestic orbit-spectrum policy is examined. Factors affecting orbit-spectrum utilization are addressed for both the homogeneous case and the nonhomogeneous case. The performance of analog and digital signals in an interference environment, interference cancellation-reduction techniques, and software for orbit-spectrum utilization studies are discussed.

Jansky, Donald M.; Jeruchim, Michel C.

395

Communication satellite payload technologies - State of the art and trends in Europe  

NASA Astrophysics Data System (ADS)

Communication satellite payload technologies are examined, in terms of past, present, and future ESA guidelines. Various existing payload systems are presented, such as Marecs, ECS, and L-Sat (which will carry four payloads). Future services within the market include 2 Mb/sec high speed data, 2-8 Mb/sec video conference, and 64 Mb/sec television distribution, and growth in these areas is dependent on traffic requirements. Pre-operational satellites are outlined, for example Telecom 1 has an estimated system capacity of 150 Mb/sec, Italsat has an expected 1180 Mb/sec, and DFS demonstrates a possible 1540 Mb/sec capacity. It is found that the 20/30 GHz band should be applied for use in wideband and high capacity trunks among heavy traffic centers. To accommodate for the noise in this waveband, the parametric amplifier developed for L-Sat must be used. Finally, development objectives for future programs include improving spectrum and geostationary orbit utilization, cost-efficiency, and standardization of systems.

Mica, G.; Coirault, R.

1982-09-01

396

Scintillation effects, mitigations and recommendations for AFSATCOM and other satellite communications systems  

Microsoft Academic Search

Signal propagation disturbances, such as scintillations, seriously degrade or disrupt operational performance of AFSATCOM and other satellite communication links. The ionospheric irregularities which cause these disturbances may develop in either a natural or nuclear environment. Natural scintillations correlate with location, time of day, season and solar activity, and are particularly disruptive to airborne (SIOP) communications terminals. The disruptions are expected

E. H. Chapin

1981-01-01

397

Evaluation of a master oscillator power amplifier (MOPA) laser diode for satellite communications  

Microsoft Academic Search

Satellite laser communications offers the potential for lightweight, high speed data transfer. One of the critical aspects of such a system are small, lightweight, high power laser sources. We will evaluate the applicability of SDL's MOPA laser diode for laser communications. Methods for achieving high data rates will be discussed. Output power and beam quality measurements will be made, as

Kevin W. Dorrian; Timothy E. Busch; Paul J. Oleski

1994-01-01

398

Impact of random jitter on a laser satellite communication system with an optical preamplifier  

Microsoft Academic Search

In this work we derive a model, which optimizes the performance of a laser satellite communication link with an optical preamplifier in the presence of random jitter in the transmitter-receiver line of sight. The system utilizes a transceiver containing a single telescope with a circulator. The telescope is used for both transmitting and receiving and thus reduces communication terminal dimensions

Anna Polishuk; Shlomi Arnon

2004-01-01

399

Optimization of a laser satellite communication system with an optical preamplifier  

Microsoft Academic Search

We derive a model that optimizes the performance of a laser satellite communication link with an optical preamplifier in the presence of random jitter in the transmitter-receiver line of sight. The system utilizes a transceiver containing a single telescope with a circulator. The telescope is used for both transmitting and receiving and thus reduces communication terminal dimensions and weight. The

Anna Polishuk; Shlomi Arnon

2004-01-01

400

In-class demonstration using amateur radio satellites for the teaching of communications engineering at the Universiti Kebangsaan Malaysia  

Microsoft Academic Search

One of the most readily available demonstrations for teaching communications engineering is the amateur radio satellites orbiting the Earth. There are several advantages to using amateur satellites for classroom demonstration. The positions of the satellites are predictable, and, unlike terrestrial communications, the links are generally line of sight and more reliable. In general, the effects of the ionosphere are very

A. F. M. Zain

1994-01-01

401

Performance limitations of a free-space optical communication satellite network owing to vibrations: heterodyne detection.  

PubMed

Free-space optical communication between satellites in a distributed network can permit high data rates of communication between different places on Earth. To establish optical communication between any two satellites requires that the line of sight of their optics be aligned during the entire communication time. Because of the large distance between the satellites and the alignment accuracy required, the pointing from one satellite to another is complicated because of vibrations of the pointing system caused by two fundamental stochastic mechanisms: tracking noise created by the electro-optic tracker and vibrations derived from mechanical components. Vibration of the transmitter beam in the receiver plane causes a decrease in the received optical power. Vibrations of the receiver telescope relative to the received beam decrease the heterodyne mixing efficiency. These two factors increase the bit-error rate of a coherent detection network. We derive simple mathematical models of the network bit-error rate versus the system parameters and the transmitter and receiver vibration statistics. An example of a practical optical heterodyne free-space satellite optical communication network is presented. From this research it is clear that even low-amplitude vibration of the satellite-pointing systems dramatically decreases network performance. PMID:18286137

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

1998-09-20

402

Structuring communication software for quality-of-service guarantees  

Microsoft Academic Search

In this paper, we propose architectural mechanisms for structuring host communication software to provide QoS guarantees. In particular, we present and evalu- ate a QoS-sensitive communication subsystem architecture for end hosts that provides real-time communication sup- port for generic network hardware. This architecture pro- vides services for managing communication resources for guaranteed-QoS (real-time) connections, such as admissio n control, traffic

Ashish Mehra; Atri Indiresan; Kang G. Shin

1996-01-01

403

Surrogate Satellite Applications and Survivability  

Microsoft Academic Search

The Tactical Satellite Communications System (TACSATCOM) established by the DOD will provide enhanced communications for US Army Ground Mobile Forces (GMF) and other services. However, in a crisis situation or during intense combat, increased communications will limit the number of users of TACSATCOM channels aboard DOD satellites to only those having top mission priority. Additionally, usage of the GMF equipment

Samuel M. Segner; Francis A. Giordano

1984-01-01

404

Innovations in microwave filters and multiplexing networks for communications satellite systems  

NASA Astrophysics Data System (ADS)

The evolution of microwave filters and multiplexers for space application is described. The advances are described within the context of the design of the overall communications subsystem. Among the topics covered are the filter technology for early commercial satellite communications, dual mode filter networks, the evolution of low-loss filter networks for 14/12 GHz satellite systems, the evolution of contiguous multiplexing for satellite systems, filter response function tradeoffs, multipath effects in satellite channels and their impact on multiplexer tradeoffs, the reduction of filter mass and size using dielectric resonator technology, and spectral efficiency criteria. Extra emphasis is placed on the multipaction and passive intermodulation considerations in designing high-power multiplexers. The impact of microwave filter technology in the channel characterization of satellite systems is described. Future R&D directions are briefly discussed.

Kudsia, Chandra; Cameron, Richard; Tang, Wai-Cheung

1992-06-01

405

Satellites and Developing Countries: Purpose, Problems, and Progress.  

National Technical Information Service (NTIS)

This thesis examines the use of satellites by countries of the Third World. The orientation will be towards communication satellites and the thin-route telecommunication services they provide. Satellite technology plays an important role in the telecommun...

L. A. Cassel

1986-01-01

406

Distributed real-equipment testing for the mobile communications services  

Microsoft Academic Search

The test activities performed during the life cycle of the telecommunication service development ensure the service quality and stability so necessary to achieve the maximum availability and reliability. The paper presents authors' contribution to remote and distributed testing for mobile communications services based on cloud computing assets and paradigms. The access solutions to the test methods were implemented for the

Virgil Cazacu; Laura Iuga; Titus Balan; Florin Sandu

2011-01-01

407

Consumer Acceptance of Personal Information and Communication Technology Services  

Microsoft Academic Search

In today's information and communication technol- ogy (ICT)-enabled service economy, there is great interest in digital service management. While the extant technology acceptance re- search has mainly studied user acceptance of various ICTs, there is a dearth of research on consumer acceptance of personal ICT services. In this paper, we extend the unified theory of acceptance and use of technology

James Y. L. Thong; Viswanath Venkatesh; Xin Xu; Se-Joon Hong; Kar Yan Tam

2011-01-01

408

Communication software for physicians' workstations supporting medical imaging services  

NASA Astrophysics Data System (ADS)

This paper describes a software communication architecture for medical imaging services. This work aims to provide to the physician the communication facilities to access and track a patient's record or to retrieve medical images from a remote database. The proposed architecture is comprised of a communication protocol and an application programming interface (API). The implemented protocol, namely the Telemedicine Network Services (TNS) protocol, has been designed in agreement with Open System Interconnection (OSI) upper layer protocols already standardized. Based on this concept an OSI-like interface has been developed capable of providing application services to the application developer, and thus facilitating the writing of medical application. TNS protocol has been implemented on top of TCP/IP communication protocols, by implementing OSI presentation and application services on top of the Transport Service Access Point (TSAP) which is provided by the socket abstraction on top of the TCP.

Orphanos, George; Kanellopoulos, Dimitris; Koubias, Stavros

1993-09-01

409

Control of satellite clusters in elliptic orbit with limited communication.  

PubMed

The cooperative control of satellite clusters in elliptical, low-Earth orbit is studied, with the goal of minimizing the necessary information passed among the individual satellites in the cluster. We investigate two possible control paradigms in this paper. The system is described using linearized equations of motion, allowing it to be expressed as a time-varying linear system. The control objective is to attain a required formation at a specified point along the orbit. A decentralized controller is used, in which each satellite maintains a local estimate of the overall state of the cluster. These estimates, along with any control information, are shared after any satellite executes a control action. The second paradigm is an extension of the first, in which state estimates are never shared, and only the control information is passed. In each case, less information being passed results in a higher computational burden on each satellite. Simulation results show cyclic errors, likely induced by higher-order terms in eccentricity and inclinations. The controller that shares state estimates performs much better than the controller that passes only control information. PMID:15220147

Chichka, David F; Belanger, Gene; Speyer, Jason L

2004-05-01

410

Ka-band High-speed Communication Systems on Small Satellites for Future Advanced Communication Networks and Earth Observations  

NASA Astrophysics Data System (ADS)

The goal of this paper is to describe the capabilities and application methods of Ka-band communication systems for small satellites indicating contributions to future advanced communication networks and Earth observations. This study is based on the actual experience on the design of the Ka-band high-speed communication system of the small satellite Flying Laptop, which is developed at the Institute of Space Systems of the Universität Stuttgart. The objectives of the Ka-band communication system is to demonstrate high-speed communications with a data rate of up to 500 Mbit/s as well as to conduct scientific Earth observations. Flying Laptop satellite is also equipped with a Ku-band signal transmitter. The attenuation of the two transmission signals in Ka-/Ku-bands are measured with ground stations to estimate the local precipitation rate. The mathematical background and operational scenario of this measurement is summarized. The received Ka-band transmission signal is measured in different meteorological conditions to identify attenuation characteristics of the Ka-band signal due to rain, clouds, trace gases and so forth, which is of great interest for utilization of Ka-band frequencies for future broadband communications.

Kuwahara, Toshinori; Lengowski, Michael; Beyermann, Ulrich; Uryu, Alexander; Roeser, Hans-Peter

411

Network centric satellite communication with IP networks based on regenerative satellite Mesh-A (RSM-A) Ka band technology  

Microsoft Academic Search

Network centric unification of diverse communication and information sharing systems is a key objective for national defense. Overall, IP-convergence is the basis for seamlessly integrating the DoD SATCOM networking and information needs with the Global Information Grid (GIG). This paper explores IP networking with the emerging Regenerative Satellite Mesh-A (RSM-A) Ka band technology. The focus is on RSM-A capabilities to

Rajeev Gopal; Steve Arnold; Lisa Orr; Syed Ali

2008-01-01

412

Group Communication in Differentiated Services Networks  

Microsoft Academic Search

The Differentiated Services (DiffServ) approach will also bring benefits for multicast applications which need quality of service support. For instance, a highly reliable multi- cast service can be provided based on the proposed Expe- dited Forwarding behavior (8). Such a service may also be used advantageously in a global computing cluster in- frastructure, e.g., for distribution of synchronization mes- sages.

Roland Bless; Klaus Wehrle

2001-01-01

413

Impairment of radio wave signal by rainfall on fixed satellite service on earth–space path at 37 stations in Nigeria  

Microsoft Academic Search

This study investigates the effect of rainfall on horizontally polarized radio waves for fixed satellite service at Ku, Ka and V bands for links to the recently launched Nigeria Communication Satellite one (NigComSat-1), for annual time availabilities of 99–99.99% in an average year for 37 stations in Nigeria. The results obtained at Ku-band downlink shows that 99.99% availability is possible

T. V. Omotosho; C. O. Oluwafemi

2009-01-01

414

Technical and economic feasibility of telerobotic on-orbit satellite servicing  

NASA Astrophysics Data System (ADS)

The aim of this research is to devise an improved method for evaluating the technical and economic feasibility of telerobotic on-orbit satellite servicing scenarios. Past, present, and future telerobotic on-orbit servicing systems and their key capabilities are examined. Previous technical and economic analyses of satellite servicing are reviewed and evaluated. The standard method employed by previous feasibility studies is extended, developing a new servicing decision approach incorporating operational uncertainties (launch, docking, et cetera). Comprehensive databases of satellite characteristics and on-orbit failures are developed to provide input to the expected value evaluation of the servicing versus no-servicing decision. Past satellite failures are reviewed and analyzed, including the economic impact of those satellite failures. Opportunities for spacecraft life extension are also determined. Servicing markets of various types are identified and detailed using the results of the database analysis and the new, expected-value-based servicing feasibility method. This expected value market assessment provides a standard basis for satellite servicing decision-making for any proposed servicing architecture. Finally, the method is demonstrated by evaluating a proposed small, lightweight servicer providing retirement services for geosynchronous spacecraft. An additional benefit of the method is that it enables parametric analysis of the sensitivity of economic viability to the probability of docking success, thus establishing a threshold for that critical value. While based on a more economically conservative approach, the new method demonstrates the feasibility of the proposed server in the face of operational uncertainties.

Sullivan, Brook Rowland

415

CAN as a spacecraft communication bus in LEO satellite mission  

Microsoft Academic Search

Low Earth orbits (LEO) typically ranges from an altitude of 100 kms to 1000 kms above the surface of Earth. LEO has a typical inclination angle ranging from 95 to 105. Satellite Mission objectives, in these orbits, are mainly Earth observation and remote sensing. In general, such missions provide greater details of the planet Earth to its inhabitants for monitoring

M. Khurram; S. M. Y. Zaidi

2005-01-01

416

A Portable L-Band Voice Transceiver for Satellite Communication.  

National Technical Information Service (NTIS)

A portable L-band voice transceiver was developed as a feasibility model and can provide a half-duplex voice link to another terminal via the L-band transponder on the Applications Technology Satellite, ATS-6. The narrow band FM transceiver utilizes comme...

J. Maruschak D. Nace

1978-01-01

417

Optical Communications Between Underwater and Above Surface (Satellite) Terminals  

Microsoft Academic Search

A multiple scattering model is used and extended to characterize the channel between underwater and airborne (satellite) terminals at optical frequencies. The effects of the air\\/sea interface are also included with approximate solutions accurate for elevation angles above 45°. The results are presented in terms of a radiance function which is related to the transform of the spatial covariance function

SHERMAN KARP

1976-01-01

418

Optical communications between underwater and above-surface (satellite) terminals  

Microsoft Academic Search

A multiple scattering model is used and extended to characterize the channel between underwater and airborne (satellite) terminals at optical frequencies. The effects of the air\\/sea interface are also included with approximate solutions accurate for elevation angles above 45 degrees. The results are presented in terms of a radiance function which is related to the transform of the spatial covariance

S. Karp

1975-01-01

419

Defining a Communications Satellite Policy System for the 21st Century: A Model for a International Legal Framework and A New _Code of Conduct_  

NASA Astrophysics Data System (ADS)

This paper addresses the changing international communications environment and explores the key elements of a new policy framework for the 21st Century. It addresses the issues related to changing markets, trade considerations, standards, regulatory changes and international institutions and law. The most important aspects will related to new international policy and regulatory frameworks and in particular to a new international code of ethics and behavior in the field of satellite communications. A new communications satellite policy framework requires systematically addressing the following points: • Multi-lateral agreements at the nation state and the operating entity level • Systematic means to access both private and public capital • Meshing ITU regulations with regional and national policy guidelines including • landing rights" and national allocation procedures. • Systematic approach to local partnerships • Resolving the issue of the relative standing of various satellite systems (i.e. GEO, MEO, and LEO systems) • Resolving the rights, duties, and priorities of satellite facility providers versus types of service prviders. Beyond this policy framework and generalized legal infrastructure there is also another need. This is a need that arises from both increased globalism and competitive international markets. This is what might quite simply be called a "code of reasonable conduct:" To provide global and international communications services effectively and well in the 21st Century will require more than meeting minimum international legal requirements. A new "code of conduct" for global satellite communications will thus likely need to address: • Privacy and surveillance • Ethics of transborder data flow • Censorship and moral values • Cultural and linguistic sensitivity • Freedom of the press and respect for journalistic standards As expanding global information and telecommunications systems grow and impact every aspect of modern life, the need for new international policy and especially new suitable standards of conduct in the field of satellite communications become ever more apparent and necessary.

Pelton, Joseph N.

1996-02-01

420

Mobile satellite services: International co-ordination, co-operation and competition  

NASA Astrophysics Data System (ADS)

In the context of a discussion of international cooperation, coordination and competition regarding mobile satellite services, it is asserted that: there will be more than one civil mobile satellite service in the 1990's; competition between these separate mobile satellite systems is inevitable; no system should enjoy monopoly protection or subsidies; and coordination and cooperation are desirable and necessary, since the available L-band spectrum is in short supply.

Lundberg, Olof

1988-05-01

421

A Verification Method for the Risk Management System of the Electric Power Grid (RMS-EPG) using Satellite Communication  

Microsoft Academic Search

In this paper, we propose a verification method for risk management system of the electric power grid (RMS-EPG) using satellite communication network. The RMS-EPG with satellite communication network should be verified with various contingencies for its design and maintenance. For the verification of RMS-PG, the proposed system composed of the satellite communication simulator and the Power flow emulator. Proposed simulator

Kyeongyuk Min; Kwangkyoon Jung; Kyuwhan O; Jongwha Chong

422

SATELLITE TERMINAL QUALITY OF SERVICE MANAGEMENT WITH AQM CONTROL  

Microsoft Academic Search

The standardization of a Return Channel via Satellite (DVB-RCS) and the satellite community efforts in term of interoperability over the last few years are expected to play, in a near future, a decisive role in Next Generation Networks (NGNs) through the integration of Satellite networks as an alternative to terrestrial networks like DSL (Digital Subscriber Line) in low terrestrial in-

Romain Delpoux; Pascal Berthou

2009-01-01

423

Research Issues in the Next Generation Group Communication Services.  

National Technical Information Service (NTIS)

The main objective of the proposed research was to investigate five important practical issues in the design of high performance, heterogeneous group communication services for constructing the next generation defense applications. These issues are: (1) F...

S. Mishra

2000-01-01

424

Network Communication as a Service-Oriented Capability  

SciTech Connect

In widely distributed systems generally, and in science-oriented Grids in particular, software, CPU time, storage, etc., are treated as"services" -- they can be allocated and used with service guarantees that allows them to be integrated into systems that perform complex tasks. Network communication is currently not a service -- it is provided, in general, as a"best effort" capability with no guarantees and only statistical predictability. In order for Grids (and most types of systems with widely distributed components) to be successful in performing the sustained, complex tasks of large-scale science -- e.g., the multi-disciplinary simulation of next generation climate modeling and management and analysis of the petabytes of data that will come from the next generation of scientific instrument (which is very soon for the LHC at CERN) -- networks must provide communication capability that is service-oriented: That is it must be configurable, schedulable, predictable, and reliable. In order to accomplish this, the research and education network community is undertaking a strategy that involves changes in network architecture to support multiple classes of service; development and deployment of service-oriented communication services, and; monitoring and reporting in a form that is directly useful to the application-oriented system so that it may adapt to communications failures. In this paper we describe ESnet's approach to each of these -- an approach that is part of an international community effort to have intra-distributed system communication be based on a service-oriented capability.

Johnston, William; Johnston, William; Metzger, Joe; Collins, Michael; Burrescia, Joseph; Dart, Eli; Gagliardi, Jim; Guok, Chin; Oberman, Kevin; O'Conner, Mike

2008-01-08

425

Calculated noise performance of a frequency hop sequence system with applications to low altitude satellite communications  

NASA Astrophysics Data System (ADS)

This research considers communication amongst a community of earth terminals through a collection of low altitude earth oriented satellites (LASAT). In one proposed LASAT system, all satellites are identical and simultaneous transmission of near identical signals from several satellites creates interference at the earth receivers. Frequency hop sequence (FHS) is a new form of frequency hopping (FH) and is the proposed spread spectrum LASAT communications technique considered in this research. In military applications, the performance of the communications system in the presence of noise only, noise and jamming, noise and multipath or synchronization errors is of interest. FHS offers some immunity to jamming and multipath. This report presents the calculated noise performance of FHS in the presence of jamming, multipath and synchronization errors. For the noise only case, the calculated probability of bit error of a FHS system using eight symbols for a 10 dB value of the ratio of input bit energy to noise power density is 0.0002.

Ozden, Mehmet T.

1990-12-01

426

The study on integrated mode of inter-satellite communication/measurement in autonomous formation flyer  

NASA Astrophysics Data System (ADS)

Considering autonomous and AD-HOC networking of AFF, such as topology, multiple access mode, integrated mode of inter-satellite communication and measurements, and data transfer protocol, are presented and studied in this paper. Inter-satellite non-coherence spread spectrum ranging via full-duplex asynchronous communication link of CCSDS Proximity-1 transfer frame is deeply researched, and Sufficient simulation and engineering experiments are implemented and plenty of results are obtained, which show that the integrated mode of intra-satellite communication and measurement achieves excellent precision, integrates multiple functions in one device with more effective utilization ratio of channel in radio link. The production of principles and technologies in this dissertation has many academic and engineering values, can be used in many fields in the future.

Li, Xue; Liu, Lei; Yang, Yi-Kang

2009-12-01

427

Low traffic density, small terminal network, and satellite antenna design for communications in the rural areas  

NASA Astrophysics Data System (ADS)

The applications of satellite communications techniques for improving the telecommunications scenario in developing countries and access to isolated and disperse users are discussed. The main issues determining the strategy for solving communications problems are summarized, and the main requirements for both the earth and space segments are outlined. System considerations for satellite-network design and the main criteria correlated to rural-area requirements are presented, and emphasis is placed on two proposed concepts for satellite multiple-access techniques: single channel per carrier/demand assignment multiple access (SCPC/DAMA) and code division multiple access/spread spectrum (CDMA/SS). A CDMA/SS network architecture design for 9600 b/s voice-communication and TV-program distribution in African countries and an onboard reconfigurable multispot antenna design for the coverage optimization of African regions are considered as examples.

Bardelli, L.; Martinino, F.; Rispoli, F.

428

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

Code of Federal Regulations, 2012 CFR

...for non-geostationary and geostationary satellite systems in frequencies allocated to the fixed-satellite service. 25.278 Section 25.278...CONTINUED) COMMON CARRIER SERVICES SATELLITE COMMUNICATIONS Technical Operations...

2012-10-01

429

47 CFR 25.146 - Licensing and operating authorization provisions for the non-geostationary satellite orbit fixed...  

Code of Federal Regulations, 2010 CFR

...authorization provisions for the non-geostationary satellite orbit fixed-satellite service (NGSO FSS) in the bands 10.7 GHz to...COMMISSION (CONTINUED) COMMON CARRIER SERVICES SATELLITE COMMUNICATIONS Applications and Licenses...

2009-10-01

430

47 CFR 25.146 - Licensing and operating authorization provisions for the non-geostationary satellite orbit fixed...  

Code of Federal Regulations, 2010 CFR

...authorization provisions for the non-geostationary satellite orbit fixed-satellite service (NGSO FSS) in the bands 10.7 GHz to...COMMISSION (CONTINUED) COMMON CARRIER SERVICES SATELLITE COMMUNICATIONS Applications and Licenses...

2010-10-01

431

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

Code of Federal Regulations, 2011 CFR

...for non-geostationary and geostationary satellite systems in frequencies allocated to the fixed-satellite service. 25.278 Section 25.278...CONTINUED) COMMON CARRIER SERVICES SATELLITE COMMUNICATIONS Technical Operations...

2011-10-01

432

Prediction of the Sun-Glint Locations for the Communication, Ocean and Meteorological Satellite  

Microsoft Academic Search

For the Communication, Ocean and Meteorological Satellite (COMS) which will be launched in 2008, an algorithm for finding the precise location of the sun-glint point on the ocean surface is studied. The precise locations of the sun-glint are estimated by considering azimuth and elevation angles of Sun-satellite-Earth geometric position and the law of reflection. The obtained nonlinear equations are solved

Jae-Ik Park; Kyu-Hong Choi; Sang-Young Park; Joo-Hyung Ryu; Yu-Hwan Ahn; Jae-Woo Park; Byoung-Soo Kim

2005-01-01

433

On-board processing concepts for Multibeam Communication Satellites - Present situation and perspectives  

NASA Astrophysics Data System (ADS)

The present paper addresses some relevant issues concerning Multibeam Communications Satellite, outlining some logical architecture trends aiming at abandoning the old 'cable-in-the-sky' concept in favor of more attractive 'switchboard-in-the-sky' features. On Board Processing (OBP) concepts must then be envisaged to increase the degree of satellite integration in the (digital) terrestrial network. Both system and technology aspects are substantiated in the paper, and potential benefits/critical areas indicated.

Ananasso, Fulvio; Saggese, Enrico

1988-12-01

434

Connecting Autoethnography with Service Learning: A Critical Communication Pedagogical Approach  

ERIC Educational Resources Information Center

This article describes a project that encourages the development of a critical-pedagogical perspective in an undergraduate small group communication class. The project provides a transition from ideology to practice by combining activities that have been connected to critical communication pedagogy--service learning and autoethnography. The…

Kahl, David H., Jr.

2010-01-01

435

A Theory of Interdependent Demand for a Communications Service  

Microsoft Academic Search

The utility that a subscriber derives from a communications service increases as others join the system. This is a classic case of external economies in consumption and has fundamental importance for the economic analysis of the communications industry. This paper analyzes the economic theory of this kind of interdependent demand. We begin by defining \\

Jeffrey Rohlfs

1974-01-01

436

An Effective Error Control Scheme for Satellite Communications  

Microsoft Academic Search

The conventional go-back-NARQ is inadequate for error control on satellite channels due to the large round-trip delay and high bit rate. The throughput efficiency of this system drops rapidly as the channel error rate increases. In this paper, a variation of the go-back-NARQ is described. This variation reduces the effect of the round-trip delay, and hence increases the system throughput

Shu Lin; P. S. Yu

1980-01-01

437

PETRA: performance enhancing transport architecture for Satellite communications  

Microsoft Academic Search

This paper presents a performance enhancing transport architecture for the satellite environment. This solution improves the network transport performance by overcoming the limits imposed by a transmission control protocol\\/Internet protocol (TCP\\/IP)-based stack suite, while maintaining the interfaces offered by it. This is an important issue since TCP\\/IP is widely used and most of the applications are based on it. The

Mario Marchese; Michele Rossi; Giacomo Morabito

2004-01-01

438

Increased Capacity Using CDMA for Mobile Satellite Communication  

Microsoft Academic Search

The performance of a spread-spectrum CDMA (code-division multiple access) system in a mobile satellite environment is analyzed. Comparisons to single-channel-per-carrier FDMA systems are presented which show that the CDMA approach provides greater capacity. Results from computer simulations, laboratory tests, and field tests of a prototype modem are also presented. The tests results show excellent performance of the modem in the

Klein S. Gilhousen; Irwin M. Jacobs; Roberto Padovani; Lindsay A. Weaver Jr.

1990-01-01

439

47 CFR 25.158 - Consideration of GSO-like satellite applications.  

Code of Federal Regulations, 2011 CFR

...158 Telecommunication FEDERAL COMMUNICATIONS COMMISSION (CONTINUED) COMMON CARRIER SERVICES SATELLITE COMMUNICATIONS Applications and Licenses Processing...following criteria: (i) After review of the application and any...

2011-10-01

440

Satellites  

SciTech Connect

The present work is based on a conference: Natural Satellites, Colloquium 77 of the IAU, held at Cornell University from July 5 to 9, 1983. Attention is given to the background and origins of satellites, protosatellite swarms, the tectonics of icy satellites, the physical characteristics of satellite surfaces, and the interactions of planetary magnetospheres with icy satellite surfaces. Other topics include the surface composition of natural satellites, the cratering of planetary satellites, the moon, Io, and Europa. Consideration is also given to Ganymede and Callisto, the satellites of Saturn, small satellites, satellites of Uranus and Neptune, and the Pluto-Charon system.

Burns, J.A.; Matthews, M.S.

1986-01-01

441

Prediction of Communication Outage Period between Satellite and Earth station Due to Sun Interference  

NASA Astrophysics Data System (ADS)

Geostationary satellites are located at an altitude of approximately 35,786km above the equator, and revolve in the same angular velocity as earth. Geostationary satellites can therefore, communicate with a ground earth station at all times. However, geostationary satellites also experience communication failure time, twice a year, closely one upon the other in spring and autumn quarters. The communication errors occur when ground station-satellite-the Sun are aligned closely, which occurs during spring and fall equinoxes. At such times, thermal noise emitted from the Sun's surface hits the rear side of the satellite and flows directly into the earth station antenna. This is called solar interference. Studies on duration calculation methods and prediction results of a solar interference phenomenon were implemented by many scientists (Vuong & Forsey 1983, Mohamadi & Lyon 1988, Lin & Yang 1989) abroad, and also by Lee et al. (1991) in Korea. To calculate the time of solar interference, information on precise position of the Sun and earth station antenna systems is necessary. Previous researches used the formula of Van Flandern (Van Flandern & Pulkkinen 1979) when calculating the Sun's position, but it has position error of about 1 arcmin. Using the precise ephemeris DE406, which published by NASA/JPL and the earth ellipsoid model, the study calculated the precise positioning of the Sun as causing error within 10 arcsec. For the verification of the calculation, we used TU media ground station located in Seongsu-dong and the MBSAT satellite operated by TU media.

Song, Yongjun; Kim, Kap-Sung; Jin, Ho; Lee, Byoung-Sun

2010-03-01

442

Airborne Protected Military Satellite Communications: Analysis of Open- Loop Pointing and Closed-Loop Tracking with Noisy Platform Attitude Information.  

National Technical Information Service (NTIS)

U.S. military assets' increasing need for secure global communications has led to the design and fabrication of airborne satellite communication terminals that operate under protected security protocol. Protected transmission limits the closed-loop tracki...

T. M. Gallagher W. D. Deike

2011-01-01

443

Characteristics of large deployable mesh reflector antennas for future mobile communications satellites  

NASA Astrophysics Data System (ADS)

A large deployable antenna is essential for effective mobile communication satellites. This paper describes the key technologies needed for such an antenna, the development plan, and the characteristics of various scale models. The electrical scale models of the mesh reflector antenna and the mechanical models of the deployable reflector have been constructed to aid in antenna design. The ultimate goal is a deployable mesh reflector antenna with 30-m diameter. The measured performance of the scale models corresponds closely to the calculated performance. These results will be extremely useful for designing large deployable mesh reflector antennas for mobile communication satellites.

Ebisui, Takashi; Iso, Akio; Orikasa, Teruaki; Sugimoto, Toshio; Sato, Shin-Ichi

1992-03-01

444

Design and characteristics of a multi-band communication satellite antenna system  

NASA Astrophysics Data System (ADS)

This paper describes feasibility studies on a multiband communication satellite antenna system and the key technologies involved in devising this system. The proposed multiband communication satellite utilizes four frequency bands, Ka (30/20 GHz), Ku (14/12 GHz), C (6/4 GHz), and S (2.6/2.5 GHz) bands. It has six-beam configurations: three multibeam and three shaped-beam configurations. The following key technologies to be developed are presented: (1) low-loss frequency selective sub-reflector for compact feeds, (2) low-loss and broad-band frequency selective surface, and (3) highly accurate and reliable mesh reflector.

Kumazawa, Hiroyuki; Itanami, Takao; Ueno, Kenji; Ohtomo, Isao

1992-03-01

445

Fleet management based on satellite positioning and communication  

NASA Astrophysics Data System (ADS)

Computerized systems for vehicle location, communication and fleet management provide permanent and direct on route access to the fleet. Thus time schedules, routes and cargo assignments can be optimized. Transport hazards can be identifed and minimized or avoided. The functionality of such a system is based on the following matched components: sufficiently accurate positioning of each vehicle based on GPS (Global Positioning System); communication system, functioning no matter what the position of the vehicle is via Inmarsat; centralized, computer based management system, which will keep the dispatcher free from routine tasks, provide hints for decision finding in tactical situations, enables access and control based on a digital map information system.

Hossfeld, Bernd

1992-07-01

446

A description of QUALCOMM Automatic Satellite Position Reporting (QASPR(R)) for mobile communications  

NASA Astrophysics Data System (ADS)

Two satellite position reporting has been introduced into the OmniTRACS mobile satellite communication system. This system significantly improves position reporting reliability and accuracy while simplifying the terminal's hardware. The positioning technique uses the original OmniTRACS TDMA timing signal formats in the forward and return link directions plus an auxiliary, low power forward link signal through a second satellite to derive distance values. The distances are then converted into the mobile terminal's latitude and longitude in real time. A minor augmentation of the spread spectrum profile of the return link allowed the resolution of periodic ambiguities. The system also locates the two satellites in real time with fixed platforms in known locations using identical mobile terminal hardware. Initial accuracies of 1/4 mile have been realized uniformly throughout the USA using a satellite separation of 22 degrees and there are no dead zones, skywaves, or cycle slips as found in terrestrial systems like LORAN-C.

Ames, William G.

447

Advanced Services: Changing How We Communicate  

Microsoft Academic Search

This paper introduces three next-generation collaboration services designed to restore the human social interactions often lost in geographically distributed work environments. These services—TeamPortal †, ConnectIcon†, and OpenChannel†—will be delivered as a trial and demonstration system on the ser- vice access, mediation, and management (SAMM) platform. SAMM technology allows service providers to use the standard Lucent Softswitch to add converged voice

Raymond O. Colbert; Diane S. Compton; Randy L. Hackbarth; James D. Herbsleb; Laurie A. Hoadley; Graham J. Wills

2001-01-01

448

Research of remote control for Chinese Antarctica Telescope based on iridium satellite communication  

NASA Astrophysics Data System (ADS)

Astronomers are ever dreaming of sites with best seeing on the Earth surface for celestial observation, and the Antarctica is one of a few such sites only left owing to the global air pollution. However, Antarctica region is largely unaccessible for human being due to lacking of fundamental living conditions, travel facilities and effective ways of communication. Worst of all, the popular internet source as a general way of communication scarcely exists there. Facing such a dilemma and as a solution remote control and data transmission for telescopes through iridium satellite communication has been put forward for the Chinese network Antarctic Schmidt Telescopes 3 (AST3), which is currently under all round research and development. This paper presents iridium satellite-based remote control application adapted to telescope control. The pioneer work in China involves hardware and software configuration utilizing techniques for reliable and secure communication, which is outlined in the paper too.

Xu, Lingzhe; Yang, Shihai

2010-07-01

449

Rain height statistics for satellite communication in Malaysia  

NASA Astrophysics Data System (ADS)

The calculation of fade margin required for 99.99% of the time availability of satellite link requires the knowledge of rain height. There is a shortage of results on rain height over Malaysian equatorial stations. The results on rain height in relation to 0 °C isotherm height (Hi) over four stations are presented. The variations of 0 °C isotherm heights for two monsoon seasons have been studied based on an analysis of radiosonde. The exceedence probability statistics of rain height are compared between the two seasons.

Mandeep, J. S.

2008-09-01

450

The Global System for Mobile Communications Short Message Service  

Microsoft Academic Search

This tutorial presents an overview of the Global System for Mobile Communications Short Message Service from the viewpoint of implementing new telematic services. The SMS offers the users of GSM networks the ability to exchange alphanumeric messages up to the limit of 160 characters. The tutorial is motivated by an acute absence of research publications in this field. The information

C. Peersman; S. Cvetkovic; P. Griffiths; H. Spear

2000-01-01

451

In-Service Science Teachers' Attitude towards Information Communication Technology  

ERIC Educational Resources Information Center

|The purpose of this study is to determine the attitude of in-service science teachers towards information communication technology (ICT) in education. The study explores the relationship between in-service teachers and four independent variables: their attitudes toward computers; their cultural perception of computers; their perceived computer…

Kibirige, I.

2011-01-01

452

Electronic Communications for Reference Services: A Case Study.  

ERIC Educational Resources Information Center

Describes services offered by the Center for Electronic Records of the National Archives and Records Administration and discusses electronic communication tools used in its reference services program, including electronic mailing lists, electronic mail, and online descriptive materials and finding aids. Provides an overview of constituency groups…

Hull, Theodore J.; Adams, Margaret O.

1995-01-01

453

Temporal broadening of ultrashort space-time Gaussian pulses with applications in laser satellite communication  

Microsoft Academic Search

In this paper, analytic expressions for the temporal broadening of narrowband space-time Gaussian pulses propagating in weak optical turbulence are derived for both near and far fields. General results are presented for nominal parameter values characterizing laser communication through the atmosphere. Specific examples are calculated for both upper atmosphere UAV-UAV cross-links and uplink\\/downlink satellite communication paths. It is shown that

Deborah E. Kelly; Cynthia Y. Young; Larry C. Andrews

1998-01-01

454

Servicing of multiple satellites using an OMV-derived transfer vehicle  

NASA Astrophysics Data System (ADS)

Servicing vehicles and supplies to be used for extending the mission life of polar orbiting satellites will be launched into orbit by expendable launch vehicles, since the Space Shuttle currently is not expected to operate in this orbital regime. The Orbital Maneuvering Vehicle or a smaller version being designed for this purpose, and its performance potential as a permanently space-based satellite servicing vehicle, are the subject of this paper. A single servicing vehicle of this class can maneuver, as required, to visit multiple user satellites in their respective orbits. Cost-effective orbit transfer techniques are essential for a viable multi-satellite servicing scenario. Such transfer modes and servicing scenarios, and the usable payload delivery performance achievable are analyzed and compared.

Graves, Carl D.; Meissinger, Hans F.; Rosen, Alan

455

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

Code of Federal Regulations, 2010 CFR

...capable of providing fixed-satellite services on a continuous...space station in the fixed-satellite service operating...the milestone has been met. Failure to file a timely certification...primary use by the Fixed-Satellite Service, subject to...

2010-10-01

456

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

Code of Federal Regulations, 2010 CFR

...capable of providing fixed-satellite services on a continuous...space station in the fixed-satellite service operating...the milestone has been met. Failure to file a timely certification...primary use by the Fixed-Satellite Service, subject to...

2009-10-01

457

Satellite-aided mobile communications limited operational test in the trucking industry  

NASA Astrophysics Data System (ADS)

An experiment with NASA's ATS-6 satellite, that demonstrates the practicality of satellite-aided land mobile communications is described. Satellite communications equipment for the experiment was designed so that it would be no more expensive, when mass produced, than conventional two-way mobile radio equipment. It embodied the operational features and convenience of present day mobile radios. Vehicle antennas 75 cm tall and 2 cm in diameter provided good commercial quality signals to and from trucks and jeeps. Operational applicability and usage data were gathered by installing the radio equipment in five long-haul tractor-trailer trucks and two Air Force search and rescue jeeps. Channel occupancy rates are reported. Air Force personnel found the satellite radio system extremely valuable in their search and rescue mission during maneuvers and actual rescue operations. Propagation data is subjectively analyzed and over 4 hours of random data is categorized and graded as to signal quality on a second by second basis. Trends in different topographic regions are reported. An overall communications reliability of 93% was observed despite low satellite elevation angles ranging from 9 to 24 degrees.

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

1980-07-01

458

OSI applied to aeronautical satellite mobile communications in EURATN  

NASA Astrophysics Data System (ADS)

The future Aeronautical Telecommunication Network ATN being standardized by ICAO (International Civil Aviation Organization) and application of OSI (Open Systems Interconnection) are described. The concepts developed by paper work have reached such a maturity that a validation step is now essential in parallel with futher ATN specification activity. This validation requires the development of an experimental ATN. This is the aim of the EURATN project. The Satcom satellite subnetwork will be part of this experimental ATN. The EURATN project will provide an experimental ATN, both for the validation aspects mentioned above and for ATM (Air Traffic Management) enhancement trials. Such experimental activities will be performed after EURATN completion, possibly in the frame of a EURATN 2 project.

Monteil, Franck

1992-07-01

459

Improving Interpersonal Communication through Community Service  

ERIC Educational Resources Information Center

|The current study sought to determine if community based gardening projects would reduce perceptions of the need to use communication devices--cell phones or text messaging--and increase the likelihood of participating in future volunteer projects. Results strongly support the predictions in that the experimental group post-test mean score of the…

Hoffman, August John; Wallach, Julie; Sanchez, Eduardo; Afkhami, Hasti

2009-01-01

460

CONNECT: a user-oriented communications service  

Microsoft Academic Search

The technology exists to produce systems for automated communication within one office or among separate offices. What does NOT exist is a methodology for making such systems EFFECTIVE and ATTRACTIVE for computer-naive users, attributes that should be considered highly important to the sucess of an office-automation system. This paper presents the generalized user's environment and the functional specification of a

Donald R. Oestreicher; John F. Heafner; Jeffrey G. Rothenberg

1974-01-01

461

77 FR 51045 - Certain Two-Way Global Satellite Communication Devices, System and Components Thereof; Notice of...  

Federal Register 2010, 2011, 2012, 2013

...Certain Two-Way Global Satellite Communication...Certain Two-Way Global Satellite Communication...FURTHER INFORMATION CONTACT: Lisa R. Barton...requested remedial orders are used in the United...regarding filing should contact the Secretary (202-205-2000...8(c)). By order of the...

2012-08-23

462

Performance and uses of a refurbished 30-m former satellite communications antenna: The Georgia Tech Woodbury Research Facility  

Microsoft Academic Search

A class of large satellite communication antennas built in the 1970s for commercial purposes comprises a potential set of large antennas useful for education, research, satellite communications, or radio astronomy upon upgrade. Many of these facilities were abandoned as the advent of low-noise electronics obviated the need for such large antennas with their associated maintenance costs. Although many have sat

David R. DeBoer; Paul G. Steffes

1999-01-01

463

The constitution and characteristics of 20 GHz band high power transmitter for communications satellite  

Microsoft Academic Search

The paper describes the design and characteristics of two 20 GHz band high-power transmitters onboard a communication satellite. The type A transmitter is a lightweight model noted for its electrical performance, while the type B transmitter is an environmental test model designed to withstand severe launching and geostationary orbit conditions. Both transmitters consist of active and standby TWT amplifiers, single

M. Nakamura; F. Kawashima; A. Iso

1975-01-01

464

Aspects of Late-Time Striation Behavior and Satellite Communication Effects.  

National Technical Information Service (NTIS)

This report is a study of aspects of plasma wave turbulence relevant to late-time striation behavior and satellite communication effects. These include: 1. Basic theory of particle diffusion due to quasi-neutral plasma modes. 2. Forms for the diffusion co...

J. L. Sperling S. R. Goldman

1979-01-01

465

Relationships between U.S. Naval Observatory, LORAN-C and the Defense Satellite Communication System  

NASA Astrophysics Data System (ADS)

The methods used in forming time scales for distant sites monitoring LORAN-C are addressed. The time transfers obtained via the defense satellite communication system (DSCS) and the data provided by this system used to calibrate these remote time scales are emphasized. The errors involved are discussed.

Charron, L. G.

1982-03-01

466

A conformal UHF antenna suitable for satellite communications by small air, land & sea sensor platforms  

Microsoft Academic Search

Today's warfighter has access to seamless global connectivity through a number of satellite communication (SATCOM) networks operating at frequencies from UHF to K band. This is especially important when performing Intelligence, Surveillance and Reconnaissance (ISR) missions with an Unmanned Air Vehicle (UAV) where a pilot may be thousands of miles removed from the platform. A very attractive radio link to

D. T. Auckland; Mark Reese

2011-01-01

467

Europe at the crossroads: The future of its satellite communications industry  

Microsoft Academic Search

Ways of adapting the European Space Agency's role to the new industrial environment of satellite communications, which is characterized by the disappearance of traditional monopolies and the introduction of competition, are presented. As far as ESA is concerned, it is found that a general consensus exists to recommend that the agency should take a much wider view of its role

Pierre Bartholome; B. Battrick

1993-01-01

468

Development of Algorithm, Architecture and FPGA Implementation of Demodulator for Processing Satellite Data Communication  

Microsoft Academic Search

Summary This paper proposes a novel VLSI architecture for the demodulator for processing satellite data communication. The overall receiver algorithm is divided into two parts: one to be implemented on an FPGA and the other on a DSP processor. A new distributed arithmetic based architecture for implementing a Sampling Rate Converter is also proposed. The main advantage of this architecture

K. R. Nataraj; S. Ramachandran; B. S. Nagabushan

2009-01-01

469

Study on the Applicability of Asynchronous Time Division (ATD) Techniques to Satellite Communications Systems, Executive Summary.  

National Technical Information Service (NTIS)

The utilization of asynchronous transfer mode (ATM) in satellite communication networks was assessed, using a user-based and a network-oriented scenario. The user scenario appears to be a good candidate for an immediate application while the situation of ...

H. Kuhlen G. Hertel M. Moerzinger A. Zambra M. Merri

1988-01-01

470

Further considerations on satellite communication systems applicable to offshore gas\\/oil exploitation activities  

Microsoft Academic Search

The system defined originally is compared with existing satellite communication systems, and items in the baseline systems concept, which may be subjected to further analysis or modification, are identified. As a result of this study, a possible 4\\/6 GHz system and a modified version of the 12 GHz baseline system concept proposed originally, are synthesized. It is concluded that the

H. Schuessler

1975-01-01

471

A PC?based Audio\\/Graphics\\/Video Image Satellite Communication Education System and its Applications  

Microsoft Academic Search

A PC?based audio\\/graphic\\/video image satellite communication education system is described in this paper Five demonstrations of this system between China and the United States are described. This system is found to have possessed potential applications in various fields. It offers some concrete suggestions for teleteaching and teleconferencing development.

Fuwen Gao; Weiwei Li; Danian Li

1989-01-01

472

Research on denoising in WDM laser inter-satellites communication system  

Microsoft Academic Search

This paper proposes a method of wavelet analysis for de-noising at receiver system in WDM laser inter-satellites communication. Background noises such as galactic noise, sunlight and etc make the received power reduce. The noisy signal is decomposed using wavelets and wavelet packets; then is transformed into wavelet coefficients and the lower order coefficients are removed by applying a soft threshold.

Chuanhua Wen; Yang Su; Yuquan Li; Li Zhou

2006-01-01

473

Effects of multipath interference in aeronautical and maritime satellite communication links  

Microsoft Academic Search

In establishing aeronautical and maritime communication links via satellite, in addition to thermal noise, further degradation factors such as the reflected multipath interference should be taken into account. This paper describes the general approach for evaluating the average probability of error with the assumption of the multipath interference characterized by the Nakagami m-distribution for its envelope. Several expressions are derived

T. Mizuno; N. Morinaga; Y. Hirata; T. Namekawa

1975-01-01

474

Trajectory tracking of a satellite communicated missile with Fuzzy and PID control  

Microsoft Academic Search

com Abstract- In this study, the trajectory of a satellite communicated missile, which is thrown from combat plane to combat plane, has been investigated with using Fuzzy and PID control seperately. The Guidance Section of Missile consists of an active radar seeker and radome, radar altimeter and antennas, and power converter. Simulations have been done with Matlab Simulink toolbox and

Mustafa Yagimli; Ugur Simsir; Hakan Tozan

2011-01-01

475

Characteristics of large deployable mesh reflector antennas for future mobile communications satellites  

Microsoft Academic Search

A large deployable antenna is essential for effective mobile communication satellites. This paper describes the key technologies needed for such an antenna, the development plan, and the characteristics of various scale models. The electrical scale models of the mesh reflector antenna and the mechanical models of the deployable reflector have been constructed to aid in antenna design. The ultimate goal

Takashi Ebisui; Akio Iso; Teruaki Orikasa; Toshio Sugimoto; Shin-Ichi Sato

1992-01-01

476

A novel AFC scheme with time diversity combining for helicopter satellite communications  

Microsoft Academic Search

In helicopter satellite communications, the periodic blockage of received signal and the carrier frequency fluctuation are the most important problems. In this paper, we propose a novel automatic frequency controller (AFC) scheme with time diversity combining. The proposed AFC generates the frequency error signal based on the time diversity combined signal. The signal-to-noise power ratio (SNR) of the frequency error

Toshiharu Kojima; B. Batbaatar; C. Batzorig; T. Fujino

2009-01-01

477

Low cost electronically steered antenna and receiver system for mobile satellite communications  

Microsoft Academic Search

The design, construction, and basic characteristics of an electronically steered, adaptive phased array antenna for land mobile satellite communications are described here. The antenna system includes an array of six microstrip stacked patch antennas, each one connected to an RF channel, which include a monolithic microwave\\/millimeter wave integrated circuit (MMIC) low noise amplifier and a commercial silicon monolithic I-Q modulator.

J. I. Alonso; J. M. Blas; L. E. Garcia; J. Ramos; J. de Pablos; J. Grajal; G. G. Gentili; J. Gismero; F. Perez

1996-01-01

478

Performance of satellite-to-ground communications link between ARTEMIS and the Optical Ground Station  

Microsoft Academic Search

The European Space Agency has built an optical ground station sited at the Observatorio del Teide operated by the Instituto de Astrofísica de Canarias. This station, equipped with a 1m telescope, has a multipurpose configuration for in-orbit commissioning and checkout of laser communication payloads. Since November 2001, the bidirectional link with satellite ARTEMIS has been established in more than 80

Angel Alonso; Marcos Reyes; Zoran Sodnik

2004-01-01

479

Satellite communications at ku, ka, and V bands: Propagation impairments and mitigation techniques  

Microsoft Academic Search

This article surveys the alternative fade mitigation techniques for satellite communication systems operating at Ku, Ka and V frequency bands. The specific phenomena influencing the propagation of radiowaves on Earth-space links are also overviewed. Emphasis is placed on modeling, experimental work carried out in the past, and practical implementations related to each mitigation technique.

Athanasios D. Panagopoulos; Pantelis-daniel M. Arapoglou; Panayotis G. Cottis

2004-01-01

480

Military satellite communications decision support system requirements analysis and user interface design  

Microsoft Academic Search

This research analyzed and decomposed U.S. Space Command missions to determine the requirements of a Military Satellite Communications Decision Support System (MDSS). Alternative functional architectures for an MDSS were evaluated and a graphical user interface prototype was developed. MDSS system requirements were derived through the combined use of the method of Critical Success Factors and the Representations, Operations, Memory Aids,

Hugh A. Henry

1993-01-01

481

Innovations in microwave filters and multiplexing networks for communications satellite systems  

Microsoft Academic Search

The evolution of microwave filters and multiplexers for space application is described. The many advances are described within the context of the design of the overall communication subsystem. Emphasis is placed on the multipaction and passive intermodulation (PIM) considerations in designing high-power multiplexers. The impact of microwave filter technology in the channel characterization of satellite systems is described. The future

Chandra Kudsia; Richard Cameron; Wai-Cheung Tang

1992-01-01

482

OWLS: a ten-year history in optical wireless links for intra-satellite communications  

Microsoft Academic Search

The application of Optical Wireless Links to intra- Spacecraft communications (OWLS) is presented here. This work summarizes ten years of developments, ranging from basic optoelectronic parts and front-end electronics, to different inorbit demonstrations. Several wireless applications were carried out in representative environments at ground level, and on in-flight experiments. A completely wireless satellite will be launched at the beginning of

I. Arruego; H. Guerrero; S. Rodriguez; J. Martinez-Oter; J. J. Jimenez; J. A. Dominguez; A. Martin-Ortega; J. de Mingo; J. Rivas; V. Apestigue; J. Sanchez; J. Iglesias; M. T. Alvarez; P. Gallego; J. Azcue; C. Ruiz de Galarreta; B. Martin; A. Alvarez-Herrero; M. Diaz-Michelena; I. Martin; F. Tamayo; M. Reina; M. Gutierrez; L. Sabau; J. Torres

2009-01-01

483

Solar Paddle Antenna on Pico-Satellite for Amateur Radio Communication  

NASA Astrophysics Data System (ADS)

This paper describes solar paddle antenna proposed in the development of Kagawa Satellite "KUKAI." KUKAI is a mother-daughter pico-satellite for technical verification of a tethered space robot. The mother and the daughter satellites communicate respectively with the ground station by amateur radio frequencies. For the purpose of simple deployment system on orbit and antenna directivity suitable for KUKAI, solar paddle antenna mounted at the edge of a solar paddle is employed. After sufficient antenna adjustment on the ground, KUKAI was launched on 23 January 2009 by the H-IIA rocket from Tanegashima Space Center. The solar paddles were successfully deployed, and communication by the solar paddle antenna was successful.

Nohmi, Masahiro; Oi, Katsumi; Takuma, Satoshi; Ogawa, Masaaki

484

Thermal analysis method of heat pipe embedded equipment panel of communications satellite  

NASA Astrophysics Data System (ADS)

The thermal analysis method for the heat pipe embedded equipment panel of communications satellite is presented. The analytical model of the honeycomb sandwich panel embedded with heat pipes is developed and evaluated by the experiments. The new method to predict temperature distribution of the entire communications equipment panel precisely without the increase of computer CPU memory size is proposed. It works even when the large number of communications transponders are put on the panel. The correctness of the method is also confirmed by the experiment.

Tsunoda, Hiroaki

485

Annual Conference of the Public Service Satellite Consortium (4th, Washington, D.C., October 11-12, 1979).  

ERIC Educational Resources Information Center

|This collection of papers delivered at the conference provides information on the current state of communications satellite applications and technology, the relationship of cable television and satellites, the role of satellites in public broadcasting, and the future of satellites in serving the needs of the public. Remarks and addresses by the…

Public Service Satellite Consortium, Washington, DC.