| 摘要 |
PROBLEM TO BE SOLVED: To stably acquire GPS positioning results with high precision by properly removing positioning errors. SOLUTION: The on-board unit is provided, which is equipped with an altitude displacement estimating means for estimating the displacement along altitudinal direction of a vehicle to a predetermined reference value and a displacement discriminating means for discriminating whether the absolute value of estimated displacement is larger than the predetermined threshold and resets the functions of a Kalman filter, when the displacement concerned is discriminated to be larger than the threshold concerned and at least altitude positioning is implemented by GPS. COPYRIGHT: (C)2007,JPO&INPIT |
