| 摘要 |
FIELD: satellite communication systems using artificial earth satellites on low-altitude circular orbits. SUBSTANCE: system uses satellites flying on geostationary orbits. Communication between any subscribers located within visibility zone of low-orbit satellite is established directly through this satellite. In case communications should be provided between subscribers who are beyond visibility zone of one satellite, this communication is established as follows. Posts of geostationary-orbit satellites are installed at ground control stations. Signal is retransmitted from sending subscriber through low-orbit satellite 1 to ground station 4 which is in visibility zone of this satellite, then to geostationary-orbit satellite post 5 (satellite 2), to control service 7 of receiving subscriber, wherefrom it is passed through low-orbit satellite directly to station of subscriber 8 receiving the signal. In this way, communication is ensured between subscribers located both within visibility zone of low-orbit satellite and in any point of globe thereby making it possible to solve the following problems: locating and watching condition of valuable, costly, and dangerous cargo on moving objects; instant data transmission from them to services controlling and tracking these objects as well as yielding, if necessary, control instructions (so-called radio detection satellite services RDSS); dispatching messages informing about state and functioning results of stationary objects. EFFECT: improved economic efficiency of building systems for satellite communication between subscribers located within visibility zone of low-orbit satellite or in any point of globe. 3 dwg¿
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