| 摘要 |
PROBLEM TO BE SOLVED: To provide a navigation apparatus and a computer program that calculate by map matching a geographical point on a road where the true current position is located as the current position.SOLUTION: With the current position measured by a GPS receiver 16 being used as the reference position, each of the geographical points close to the reference position on roads within a prescribed distance range from the reference position is set as a candidate geographical point. Further, in accordance with the result of evaluation conducted by using as one of evaluation elements the distance Lm between the current reference position P(0) and the immediately preceding reference position P(-1) and the absolute value of the difference (Lm-Lr) between the distance Lr of an evaluation object candidate geographical point Pr(0) and a candidate geographical point Pr(-1) previously calculated on the road where the evaluation object candidate geographical point Pr(0) is situated, the current position is calculated out of the candidate geographical points.SELECTED DRAWING: Figure 3 |
