In a communications navigation system, data is transmitted and received between a navigation base apparatus provided at a navigation base and each of a plurality of navigation apparatuses provided in moving bodies such as vehicles using communication. A determining section of the navigation base apparatus...http://www.google.de/patents/US6314369?utm_source=gb-gplus-sharePatent US6314369 - Communications navigation system, and navigation base apparatus and navigation apparatus both used in the navigation system
