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

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

Application of advanced on-board processing concepts to future satellite communications systems: Bibliography

Abstracts are presented of a literature survey of reports concerning the application of signal processing concepts. Approximately 300 references are included

Second year technical report on-board processing for future satellite communications systems

Advanced baseband and microwave switching techniques for large domestic communications satellites operating in the 30/20 GHz frequency bands are discussed. The nominal baseband processor throughput is one million packets per second (1.6 Gb/s) from one thousand T1 carrier rate customer premises terminals. A frequency reuse factor of sixteen is assumed by using 16 spot antenna beams with the same 100 MHz bandwidth per beam and a modulation with a one b/s per Hz bandwidth efficiency. Eight of the beams are fixed on major metropolitan areas and eight are scanning beams which periodically cover the remainder of the U.S. under dynamic control. User signals are regenerated (demodulated/remodulated) and message packages are reformatted on board. Frequency division multiple access and time division multiplex are employed on the uplinks and downlinks, respectively, for terminals within the coverage area and dwell interval of a scanning beam. Link establishment and packet routing protocols are defined. Also described is a detailed design of a separate 100 x 100 microwave switch capable of handling nonregenerated signals occupying the remaining 2.4 GHz bandwidth with 60 dB of isolation, at an estimated weight and power consumption of approximately 400 kg and 100 W, respectively

Proceedings of the Second International Mobile Satellite Conference (IMSC 1990)

Presented here are the proceedings of the Second International Mobile Satellite Conference (IMSC), held June 17-20, 1990 in Ottawa, Canada. Topics covered include future mobile satellite communications concepts, aeronautical applications, modulation and coding, propagation and experimental systems, mobile terminal equipment, network architecture and control, regulatory and policy considerations, vehicle antennas, and speech compression

Proceedings of the Third International Mobile Satellite Conference (IMSC 1993)

Satellite-based mobile communications systems provide voice and data communications to users over a vast geographic area. The users may communicate via mobile or hand-held terminals, which may also provide access to terrestrial cellular communications services. While the first and second International Mobile Satellite Conferences (IMSC) mostly concentrated on technical advances, this Third IMSC also focuses on the increasing worldwide commercial activities in Mobile Satellite Services. Because of the large service areas provided by such systems, it is important to consider political and regulatory issues in addition to technical and user requirements issues. Topics covered include: the direct broadcast of audio programming from satellites; spacecraft technology; regulatory and policy considerations; advanced system concepts and analysis; propagation; and user requirements and applications

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

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

Proceedings of the Mobile Satellite Conference

A satellite-based mobile communications system provides voice and data communications to mobile users over a vast geographic area. The technical and service characteristics of mobile satellite systems (MSSs) are presented and form an in-depth view of the current MSS status at the system and subsystem levels. Major emphasis is placed on developments, current and future, in the following critical MSS technology areas: vehicle antennas, networking, modulation and coding, speech compression, channel characterization, space segment technology and MSS experiments. Also, the mobile satellite communications needs of government agencies are addressed, as is the MSS potential to fulfill them

Study of Rain Attenuation Calculation and Strategic Power Control for Ka-Band Satellite Communication in India

The tremendous worldwide growth in the use of Internet and multimedia services prompted the ambitious planning for evolution of commercial and broadband satellite communication systems. The traditional C and Ku bands in satellite communications are getting crowded, So the systems are moving towards higher frequency ranges above 20 GHz. The Ka-band (18-40 GHz) frequency spectrum has gained attention for satellite communication. The inherent drawback of Ka-band satellite system is that increase in signal distortion resulting from propagation effects. Atmospheric attenuation in Ka-band is always severe, especially in the presence of rain. Thus, New technologies are required for Ka-band systems, such as multiple hopping antenna beams and regenerative transponders to support aggregate data rates in the range of 1 - 20 Gbps per satellite, which can provide DTH, HDTV, mobile and fixed Internet users with broadband connection. Currently in India C and Ku-band frequencies are being used for commercial satellite communications. In future Ka-band will be used for wideband applications. Keeping in view of the socio-economic and geographical diversities of India. Propagation studies are essential for estimation of attenuation, so that Ka-band satellite links operating in different parts of Indian region can be registered appropriately. Ka-band system is recognized as a new generation in communication satellites that encompasses a number of innovative technologies such as on board processing (OBP) for multimedia applications and switching to provide two way services to and from small ground terminals. To do this efficiently multiple pencil like spot beams are used. One distinct feature of this propagation being used to address this problem is Satellite Spot-Beam. To design effective satellite communication system, the arrangement of spot beam locations in Indian subcontinent, the study and analysis of link availability for Kaband satellite communication in various geographically separated spot beams in India using statistical data is necessary. Based on global rain models integrated with the link budget, the study allows us to examine major system design issues encountered in Ka-band satellite communication that are susceptible to propagation impairments. This system can be flexible enough to increase power on specific transmissions to compensate for local weather conditions. This can make better use of the available bandwidth than C or Ku-band satellite, and more users can get higher level of services