| 摘要 |
PROBLEM TO BE SOLVED: To provide a new technique for shortening the time required for capturing a satellite signal. SOLUTION: In a satellite signal-capturing unit 21 of a baseband processing circuit unit 20, a reception signal r(t) obtained by receiving a GPS satellite signal transmitted from a GPS satellite is made differential in a reception signal differential circuit section 211 to produce a differential code signal w(t-T) of CA code. Furthermore, a replica signal CA<SB>R</SB>(t) generated by a replica signal-generating section 213 is made differential in a replica signal differential circuit section 215 to produce a differential replica signal w<SB>R</SB>(t-T). Then, correlation processing between the differential code signal w(t-T) and the differential replica signal w<SB>R</SB>(t-T) is performed in a correlation processing section 217 and a correlation value P(Δt) is output to a CPU 25. Then, the GPS satellite signal is captured based on the correlation value P(Δt) by the CPU 25. COPYRIGHT: (C)2011,JPO&INPIT |
