Patent ID: 6591186
Filing Date: 2003-07-08
Classification: G01C,G08G

Abstract:
A vehicle navigation device comprising: a sensor which outputs a pulse signal corresponding to a traveling distance of a vehicle; a vehicle display device which displays, based on the pulse signal, vehicle information including the traveling distance; and a navigation unit which receives distance data related to the traveling distance, obtained by processing the pulse signal, being outputted from the vehicle display device or the pulse signal at a certain reception period to calculate a present position of the vehicle, and controls the vehicle display device to display road traffic information including a display synthesized with the present position on a map on the basis of map data read from a map information memory medium, the vehicle navigation device characterized in that in the case where the navigation unit can not receive the distance data or the pulse signal within the reception period, an estimated value of a current value to be received is obtained from a variation between a value inputted previously and a value inputted the time before, and the navigation unit calculates the present position on the basis of the estimated value.