| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide a GPS timepiece with a time correction function capable of securely acquiring time information from a GPS signal while suppressing power consumption. <P>SOLUTION: When a reception environment of a GPS signal is bad and a reception level does not reach a predetermined threshold, reception operation is performed at intervals of one hour (first predetermined time), only acquisition operation is performed at this time, and a reception system concerned with the reception operation is in a halt state. In an environment in which a reception state is not so bad, but not good enough to obtain correct GPS time information, reception operation is performed at intervals of four hours (second predetermined time), and up to GPS time acquisition and comparison processing with an internal timer are performed in addition to the acquisition operation. Consequently, while the reception environment is bad, only a check on a correlation value by the acquisition operation is made and the reception operation is frequently repeated to keep a watch without missing a chance for recovery, and when the reception environment becomes better, up to the GPS time information is acquired to increase chances for time correction. <P>COPYRIGHT: (C)2013,JPO&INPIT |
