Vehicular navigation system

摘要

The present invention has been made to provide a vehicular navigation system which is capable of lowering the cost of detecting road data stored in order in the outgoing trip, using the road data as resources in the return trip, and determining a route meeting the requirements of the user. According to a vehicular navigation system of the present invention, while a vehicle is traveling on a road having bidirectional data along an outgoing route from a starting point to a destination, a road on the opposite side of the road on which the vehicle is traveling is stored as return route data with a lowered cost of route determination. Such storing operation is performed for each node passed by the vehicle. The return route data thus stored are used to determine a return route. <IMAGE>