SYNTHETIC NAVIGATION DATA FOR HIGH SENSITIVITY GLOBAL POSITIONING SYSTEM RECEIVER

摘要

PROBLEM TO BE SOLVED: To provide synthetic navigation data for high sensitivity global positioning system receiver. SOLUTION: The SPS receiver is provided with a radio receiver for measuring pseudoranges to a satellite turning around an orbit, a local real-time clock having an accuracy within three seconds of true SPS system time, and a communication channel for receiving retransmission of NAV data broadcast from a server. Such a server is correlated with a unique exclusive navigation receiver capable of directly receiving the satellite signal strong enough to achieve demodulation of those reliable NAV data for SPS system. The SPS receiver composes its own NAV data from both time data supplied from the local real-time clock and satellite/orbit calendar data supplied from the server in retransmission of NAV data broadcast. Therefore, this SPS receiver can operate even in a weak signaling environment normally impossible. COPYRIGHT: (C)2004,JPO