Position detection apparatus and position detection program

摘要

A position detection apparatus 1 includes a storage unit 60 for storing map information including road information; a detection unit 20 for detecting information for calculating an absolute position Xc(t) of a moving object; a position calculation unit 110 for calculating the position Xc(t) and an error variance relating to an error of the object from the detected information; a read-out unit 121 for reading out from the storage unit 60 the road information of a road relating to the position Xc(t); an existence probability calculation unit for calculating an existence probability of the object on the road from the position Xc(t), the error variance, and the read-out road information; a selection unit 123 for selecting a position whose existence probability is maximum out of the existence probability; and a map-matching processing unit 122 for making the selected position a position XI(t) of the object on the road.