| 摘要 |
PROBLEM TO BE SOLVED: To reduce a time to first fix (TTFF).SOLUTION: In a position calculation device 1, it is determined whether or not orbit information of a GPS satellite 3 stored to a storage part satisfies s prescribed usability condition. When a result of determination is negative determination, positioning support information is acquired from an IMES transmitter 5 which is a kind of ground communication device for transmitting positioning support information to be a base of calculation of orbit information. The acquired positioning support information is used to calculate orbit information, the orbit information stored to the storage part is updated, a signal from the GPS satellite 3 and the orbit information stored to the storage part are used to calculate a position of the position calculation device 1. |
