| 摘要 |
PURPOSE:To utilize the frequency of a transponder effectively by applying time division multiplex to a user data with small transmission capacity from a master earth station to plural reception only slave earth stations, sending the processing result in a single carrier, and controlling a communication network with identification information or the like added to a frame. CONSTITUTION:A signal sent from a transmission HUB station A is amplified and frequency-converted by a transponder B of a communication satellite, received simultaneously with an antenna C1 of each reception only satellite station C, amplified by an outdoor equipment C2 and frequency-converted into an intermediate frequency band. The converted signal is demodulated into a base band at a phase demodulator C4 of an outdoor equipment C3, a frame is read by a multiplexer demultiplexer C5 and a user data sent to each terminal equipment of each reception only earth station C is discriminated based on an address, an ID and frame information added by the transmission HUB station A and sent to each data port. The user data sent to terminal equipments of other reception only earth stations C is disregarded. Thus, the frequency of the transponder B of the communication satellite is utilized effectively. |
