| 摘要 |
PURPOSE:To measure a position with high accuracy even when a DOP (Dilution of precision) value is large, by providing an antenna, a pseudo range measuring circuit, a satellite data reproducing and holding circuit, a satellite arrangement calculation part, a satellite selection part, a position arithmetic part, a display device, a data input part, etc. CONSTITUTION:The pseudo range measuring circuit 2 inputs a satellite radio wave received by the antenna 1 and supplies satellite data on each satellite to the data reproducing and holding circuit 3 and also finds and outputs its roughly calculated distance to the position arithmetic part 6. The circuit 3 holds the satellite data and data from the data input part 9. The satellite arrangement calculation part 4 inputs the number of an acquired satellite and satellite data on each satellite from the circuit 3, decides whether or not the number of acquired satellite reaches a measurable number (3), and calculates the satellite arrangement of the acquired satellites, and the satellite selection part 5 calculates DOP values A1, A2,..., as to various groups of satellites to the current position of a vehicle based on the calculated arrangement. The position arithmetic part 6 inputs pseudo range and satellite data and computes the vehicle position, which is displayed 8. |
