2,301 research outputs found
Sharing the 620-790 MHz band allocated to terrestrial television with an audio-bandwidth social service satellite system
A study was carried out to identify the optimum uplink and downlink frequencies for audio-bandwidth channels for use by a satellite system distributing social services. The study considered functional-user-need models for five types of social services and identified a general baseline system that is appropriate for most of them. Technical aspects and costs of this system and of the frequency bands that it might use were reviewed, leading to the identification of the 620-790 MHz band as a perferred candidate for both uplink and downlink transmissions for nonmobile applications. The study also led to some ideas as to how to configure the satellite system
Guidelines for spaceborne microwave remote sensors
A handbook was developed to provide information and support to the spaceborne remote sensing and frequency management communities: to guide sensor developers in the choice of frequencies; to advise regulators on sensor technology needs and sharing potential; to present sharing analysis models and, through example, methods for determining sensor sharing feasibility; to introduce developers to the regulatory process; to create awareness of proper assignment procedures; to present sensor allocations; and to provide guidelines on the use and limitations of allocated bands. Controlling physical factors and user requirements and the regulatory environment are discussed. Sensor frequency allocation achievable performance and usefulness are reviewed. Procedures for national and international registration, the use of non-allocated bands and steps for obtaining new frequency allocations, and procedures for reporting interference are also discussed
ACTS propagation terminal prototype planning and design
The planning and design of a prototype propagation receiving terminal for beacon signals at 27 and 20 GHz bands are examined. The developmental plan is discussed, followed by technical design considerations including, the Advanced Communications Technology Satellite (ACTS) system salient features and frequency plan, beacon signal parameters and specifications, system calculations, and terminal hardware design issues
Cost benefit analysis of space communications technology. Volume 2: Final report
For abstract, see preceding accession
Computer-aided communication satellite system analysis and optimization
The capabilities and limitations of the various published computer programs for fixed/broadcast communication satellite system synthesis and optimization are discussed. A satellite Telecommunication analysis and Modeling Program (STAMP) for costing and sensitivity analysis work in application of communication satellites to educational development is given. The modifications made to STAMP include: extension of the six beam capability to eight; addition of generation of multiple beams from a single reflector system with an array of feeds; an improved system costing to reflect the time value of money, growth in earth terminal population with time, and to account for various measures of system reliability; inclusion of a model for scintillation at microwave frequencies in the communication link loss model; and, an updated technological environment
Disaster warning system: Satellite feasibility and comparison with terrestrial systems. Volume 2: Final report
For abstract, see Vol. 1
Spectrum Usage for 5G Mobile Communication Systems and Electromagnetic Compatibility with Existent Technologies
The increased demand of consumers on services in the mobile broadband environment with high data rate and developed mobile broadband communication systems will require more spectrum to be available in the future. New technologies as well as the existing services require frequencies for their development. In this chapter, we investigate the available and potential future mobile terrestrial radio frequency bands (5G)—worldwide and in Europe. An insight into the mobile spectrum estimate is provided. Characteristics and requirements of IMT-2020, future possible IMT frequency bands, and examples of 5G usage scenarios are also addressed in the chapter. Electromagnetic compatibility evaluation methods are provided mainly focusing on existent mobile technologies below 1 GHz where also 5G technologies will be developed in the future. It is stressed that the radio frequency spectrum is a limited national resource that will become increasingly precious in the future
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