| 摘要 |
PURPOSE:To allow the system not to be made large in the circuit scale even when a mobile station is used as a reception section by using a chirp signal so as to measure the position thereby solving a problem of synchronization. CONSTITUTION:A chirp signal from a base station is multiplied with a modulated position measuring signal, the result is synthesized with an SCPC signal, the result is arranged in a prescribed frequency interval location and then sent to a transmission IF section for a communication satellite. Signals from three communication satellites are received by an antenna high frequency section, branched into three by a branching device 14 and inputted to a demodulation circuit (15-1-15-3). A correlation device 20 multiplies a received chirp signal and a local chirp signal to take the correlation of the both. A timing signal generating circuit 22 adjusts the output timing of a clock signal so that a frequency error is made zero thereby controlling a local chirp signal generating circuit 21. A position measuring signal demodulator 24 receiving the output of the correlation device 20 reproduces accurately a timing signal required for measuring the position. |
