| 摘要 |
PURPOSE:To shorten the talk time with and enhance the secrecy of a differential GPS position measuring device using telephone circuit. CONSTITUTION:From a mobile station side transmit/receive part 12, a mobile station gives a signal transmit request to a base station side transmit-/receive part 6 by issuing a correction error request at any time desired by the user, and a talk is commenced. By an encoding part 4, the base station having received the transmit request encodes the error information at the time under control of a transmit control part 5 and transmits from the transmit/receive part 6. The mobile station receives the encoded error information via the mobile station side transmit/receive part 12, interpreting the code by a code interpreting part 13 after the end of the talk, and corrects the position measuring position which is calculated as the correction data from the satellite track data by a correction position sensing part 14. Thereby high precision position measuring can be done with secrecy. |
