| 摘要 |
PURPOSE: To reduce the processing burden of a present location calculating device without lowering its present location calculating reliability so much when its vehicle travels along a highway. CONSTITUTION: A microprocessor 24 repeatedly performs such a process that the microprocessor 24 selects locations obtained by matching the locations found by moving candidate points found last time by the traveling distance of its own vehicle to a road through map matching and locations which are not matched to the road as candidate points and calculates a candidate point which is to be determined as the present location of the vehicle from the reliability of each candidate point. When a candidate point generated from the candidate points which are matched to a highway and calculated as the present location of the vehicle last time is continuously selected as the present location of the vehicle while the vehicle travels a prescribed distance, the microprocessor 24 limits the number of candidate points used next time for finding new candidate points in order of reliability. However, the microprocessor 24 tries as much as possible to make a prescribed number of candidate points matched to the highway to be contained in the candidate points used next time for finding the new candidate points. |
