| 摘要 |
PROBLEM TO BE SOLVED: To improve the position measurement accuracy of autonomous navigation, by performing highly accurate calibration even in the case that a large error is present in a GPS speed itself in the car speed pulse coefficient calibration method of a navigation device provided with a GPS for receiving satellite radio waves from a GPS satellite, and obtaining the information of an azimuth, a position and a speed. SOLUTION: GPS speed error distribution is calculated based on GPS satellite arrangement and the geometrical accuracy degradation index of the GPS (step S2) and whether or not the GPS speed in an advancing azimuth is reliable is judged by the obtained GPS speed error distribution (step S3). Only when the GPS speed is reliable as a result, the calibration of a car speed pulse coefficient is performed with the GPS speed as a reference (step S4). Then, an advancing distance is calculated from a car speed pulse number and the car speed pulse coefficient (step S5). |
