NAVIGATION SYSTEM, PERSONAL DIGITAL ASSISTANT, AND MODE CONTROL METHOD IN PERSONAL DIGITAL ASSISTANT

摘要

PROBLEM TO BE SOLVED: To continue a route guide in a region out of a communication range where the personal digital assistant cannot communicate with a route retrieval server, in a communication type navigation system.;SOLUTION: The route search server 20 supplies, to the personal digital assistant 30, map data of a predetermined range demanded from the personal digital assistant 30 and guide data including the guide route obtained by retrieving a route from a start point to a destination based on the route retrieval condition transmitted from the personal digital assistant 30, and the personal digital assistant 30 displays a map and/or guide route on a displaying means. The personal digital assistant 30 has a GPS positioning means 35 that has a plurality of operation modes including a map mode for displaying a map and a turn mode for displaying a guide without displaying the map and positions the current position individually, and a mode switching means 38. When the map data cannot be received from the route search server 20, the mode switching means 38 switches the operation mode to the turn mode.;COPYRIGHT: (C)2007,JPO&INPIT