| 摘要 |
PURPOSE:To receive a signal without searching in frequency over a wide range at a simple earth station by obtaining a signal of the simple earth station received by a fixed earth station through a satellite from a reference frequency and sending the signal while deviating the transmission frequency for the share. CONSTITUTION:A signal from the reference oscillator 4 for transmission and reception in common in multiplied by N and M times by multipliers 5-1, 5-2 in the mobile simple earth station of the satellite communication system, the result is subject to frequency conversion by a signal from a modulator 7-1 and a reception low noise amplifier 10-1 by frequency converters 6-1, 6-2 and the result is sent respectively to a power amplifier 9-1 and the demodulator 5-2. The output of an amplifier 9-1 is sent to a satellite in a frequency fT via a diplexer 11-1 and an antenna 12-1 and a reception signal in a frequency fR is inputted to the amplifier 10-1 via the antenna and the diplexer. The frequency ftd received via the satellite is demodulated by a demodulator 8-1 in the fixed earth station, a deviation DELTAfT from the reference frequency is detected, it is subject to M/N times by a multiplier 5-3 to send the signal in frequency ffu deviating the transmission frequency from the reference frequency by DELTAfR.
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