METHOD AND SYSTEM FOR MAP DATA UPDATE OF CAR NAVIGATION DEVICE, CAR NAVIGATION DEVICE, AND MAP INFORMATION SERVER

摘要

PROBLEM TO BE SOLVED: To obtain only necessary updated map data through simple operation at a low communication cost. SOLUTION: A car navigation device searches for a route under search conditions that an user indicates by using its own map data and transmits the used search conditions, a predicted travel distance and version information of used map data, to a map information server. The map information server calculates a predicted travel distance by making a route search with the same search conditions and the same algorithm by using updated map data. When there is a difference between the two predicted travel distances, version information of section map data of areas along the route searched for by the server is compared with version information received from the car navigation device and map difference data for matching the section map data of the car navigation device with the section map data of the server are extracted and transmitted to the car navigation device to update the map data of the car navigation device. COPYRIGHT: (C)2006,JPO&NCIPI