| 摘要 |
PROBLEM TO BE SOLVED: To provide a differential GPS apparatus by which information on error correction data can be transmitted by a communicating operation between existing vehicles by a method wherein a radio communicating operation can be performed between a plurality of moving bodies and the present position of an own moving body and the error correction data are transmitted to another moving body. SOLUTION: When a processing operation is started, a control part judges, in step 120 (S120), whether a prescribed time has elapsed or not. The prescribed time refers to a receiving cycle time in which a GPS signal is received. When its judgment is YES, the processing operation advances to S126 so as to execute a transmission processing operation. When its judgment is NO, the processing operation advances to S122 so as to judge whether the advance route of a moving body is situated in a part before being changed by a crossing, a curve or the like. When the judgment is YES, the processing operation advances to S126 so as to execute the transmission processing operation. When the judgment is NO, the processing operation advances to S124 so as to judge whether the request-to-send of a transmission frame is received from another moving body. When the judgment is YES, the processing operation advances to S126 so as to execute a transmission processing operation. When the judgment is NO, the processing operation is returned to S120 so as to execute the same processing operation repeatedly. In this manner, information regarding error correction data can be received by a communicating operation between vehicles so as to enhance the function of a differential GPS apparatus. |
