摘要:

AbstractSatellites are considered in arbitrary orbits, and interference between them and other satellites or earth‐stations is calculated. The composite interference from a complete system is found by summing over the set of visible satellites. One starts with the Keplerian orbital parameters and assumed antenna patterns and transmitter characteristics. Using classical orbital mechanics and a series of co‐ordinate transformations, one determines the location of any satellite in the frame of reference of any other satellite or earth‐station. Conventional interference methods are then used to find the r

ISSN:0737-2884    

DOI:10.1002/sat.4600120112

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1994

数据来源: WILEY

摘要:

AbstractAn option being considered by current and prospective mobile satellite service (MSS) operators is the use of constellations of non‐geostationary orbit (NGSO) satellites to provide global personal communications. The scarcity of free spectrum, together with the bandwidth typically required, means that any new MSS system must consider sharing spectrum with other systems and services. Spectrum sharing must be based on defined interference criteria being satisfied. When multiple NGSO satellites are considered there is no accepted method for assessing interference. This paper describes a model used as the basis for a computer simulation of interference scenarios involving MSS, fixed service (FS) and fixed satellite service (FSS) systems. The simulation includes NGSO dynamics, constellations of MSS satellites with multi‐spot antennas, multiple geostationary FSS satellites and multiple hop FS links. Interference events are based onC/Icalculations, and statistics, such as the percentage of time that theC/Ifalls below a required protection ratio, are calculated. More generallyC/Icumulative distribution functions are produ

ISSN:0737-2884    

DOI:10.1002/sat.4600120113

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1994

数据来源: WILEY

摘要:

AbstractThis paper discusses networking issues associated with the provision ofL/S‐band personal satellite communications. Both the UMTS and IMT‐2000 third generation mobile communication concepts have identified the need for a satellite component as part of their overall structure. The work is mostly based on the ESA‐developed medium altitude global satellite system (MAGSS‐14).1It is, therefore, mainly relevant to MEO (medium earth orbit) constellations but most ideas can also be extended to LEO (low earth orbit) constellations. After examining user and service requirements the specific networking issues associated with personal satellite communications are reviewed. A network architecture is then proposed which takes these restrictions into account. Based on this network architecture, network signalling requirements, more specifically those relevant to network common control channels, are es

ISSN:0737-2884    

DOI:10.1002/sat.4600120114

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1994

数据来源: WILEY

ISSN:0737-2884    

DOI:10.1002/sat.4600120101

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1994

数据来源: WILEY