| 摘要 |
PURPOSE:To automatically set initial information, by receiving a signal from one artificial satellite to obtain initial information necessary for shifting to the normal operation. CONSTITUTION:A CPU8 executes a program of starting time at the start up of the operation. First, a PN signal PNS is generated from a PN signal generation circuit 7 while the center frequency of a Doppler shift locking VCO10 is set and changed sequentially until a PN lock loop and a Doppler shift lock loop are locked. With the locking thereof, the CPU8 pick up time information and orbit information of a satellite from a received signal LDA fed by a demodulation circuit 12 to compute the rough position of an observing point. Finally, the CPU8 pick up orbit information of all artificial satellites from the signal LDA and then, executes the normal operation program. This eliminates the preliminary storage of initial information. |
