Bi-directional multimedia satellite communication system using ultrasmall user terminals

Citation
K. Ohata et al., Bi-directional multimedia satellite communication system using ultrasmall user terminals, ACT ASTRONA, 48(5-12), 2001, pp. 401-409
Citations number
11
Language
INGLESE
art.tipo
Article
Categorie Soggetti
Aereospace Engineering
Journal title
ACTA ASTRONAUTICA
ISSN journal
0094-5765 → ACNP
Volume
48
Issue
5-12
Year of publication
2001
Pages
401 - 409
Database
ISI
SICI code
0094-5765(200103/06)48:5-12<401:BMSCSU>2.0.ZU;2-2
Abstract
NTT started development of a multimedia satellite communication system to p rovide a medium for Internet access in 1995. This system, which entered com mercial service in 1998, uses a hybrid network consisting of a high-speed s atellite forward link and terrestrial access links. To meet the increasing demand for low-cost and ubiquitous access links, a second-generation system equipped with satellite transmitting functions is now being developed. The user terminal design calls for a DTH-sized receiver antenna and a transmis sion power of less than 0.1 W, which will make it suitable for use in homes and small offices. The access link signals from the user terminals are sup erimposed onto the high-speed TDM forward link signal for efficient use of the frequency band. The transmission power from the user terminal is signif icantly low compared to that of the forward link signal, a novel interferen ce cancellation technique is introduced. A channel assignment scheme called "channel reservation with rapid release" is introduced for both efficient use of the channels and higher transmission throughput. The forward link si gnal is completely compatible with the first-generation system, and the dat a rate is about 30 Mb/s. The paper describes the system's configuration, the central earth station's configuration, and the key technologies of the radio system and access con trol system. (C) 2001 International Astronautical Federation. Published by Elsevier Science Ltd.