| 摘要 |
PROBLEM TO BE SOLVED: To attain shortening of a time required for initial acquisition even when initial setting is made at different positions at the time when power is charged, by a method in which the present position is calculated from a radio broadcasting signal received and the position is registered as the initial set position. SOLUTION: A GPS receiver 1 receives a GPS signal through a GPS antenna 3 and outputs positioning information such as position data and time data to an arithmetic device 2. A receiver 5 of radio broadcasting signals receives radio signals of AM, FM, etc., by means of an antenna 4. The frequencies of the received radio signals are different according to transmitting stations and they can be calculated by calculation device 6. Moreover, a storage device 7 in which receivable frequencies of the radio signals and regions in which the frequencies are receivable are provided. The present position of the GPS receiver 1 is estimated by a calculating device 8 comparing the calculated frequency with data stored in the storage device 7 and this estimated position is registered as an initial estimated position. |
