Patent ID: 7133773
Filing Date: 2006-11-07
Classification: G01C,G08G

Abstract:
1. A terminal device in a map distribution system, comprising: a communication unit configured to transmit information to an information center that distributes map information and to receive information from the information center; a map storing unit configured to store the map information received by the communication unit; a control information storing unit configured to store control information associated with the map information stored in the map storing unit; a communication control unit configured to control the communication unit to transmit the control information stored in the control information storing unit to the information center on prescribed times so as to receive latest control information transmitted from the information center; a control unit configured to rewrite the control information stored in the control information storing unit to the latest control information; and a map updating unit configured to determine that the map information stored in the map storing unit is to be updated when the map updating unit compares the map information stored in the information center and the map information stored in the map storing unit while referring to the control information stored in the control information storing unit and judges that the map information stored in the information center is newer than the map information stored in the map information storing unit.