| 摘要 |
PROBLEM TO BE SOLVED: To make the current position on a map displayed appropriately, when traveling on a road in a mountain-ringed area, in a navigation system. SOLUTION: An arithmetic operation section 1 of the navigation system is configured so as to execute a step of acquiring a three-dimensional current position from a GPS receiving device 7; a step of calculating the turning frequency of a vehicle in a prescribed range; a step of calculating the number of intersections in a prescribed range from the acquired three-dimensional current position; a step of estimating whether the road, on which the vehicle traveling, is one in the mountain-ringed area, based on the number of the intersections and the turning frequency; a step of displaying the current position on the map using the acquired three-dimensional current position, when such an estimation result that the travel road is not one in the mounting-ringed area; and a step of acquiring a two-dimensional current position from the GPS receiving device 7 and displaying the current position on the map, by using the two-dimensional current position, when such an estimation result that the travel road is one in the mounting-ringed area. COPYRIGHT: (C)2006,JPO&NCIPI |
