| 摘要 |
PROBLEM TO BE SOLVED: To detect a current location by reliably receiving GPS signals from satellites without incurring the problem that a significant voltage drop occurs in a battery to bring devices to breakdown even when a coin cell battery or another compact battery is used as a power supply. SOLUTION: An RF part 2 is intermittently changed over from nonoperating mode, which does not consume the electric power of a battery to operating mode, which consumes the electric power of the battery only for a short period to acquire part of five items of the first to fifth subframe data time-serially transmitted from satellites from among GPS signals received during the period of operating mode. In operation mode at another timing, the remaining subframe data is acquired to determine location information on the basis of the acquired five items of subframe data. COPYRIGHT: (C)2008,JPO&INPIT
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