Dynamic route guidance system for vehicles

The system has transmitter-receiver (10) obtaining traffic data by contacting optical or radio beacon installed along route. Traffic data for 10 km. radial zone in front are obtained. Degree of congestion is classified as 'difficult' or 'fluid'. Data are sent to control unit (ECU) (12) for vehicle information communication system (VICS). Antenna (14) and receiver (16) are installed. Multiplexed FM signal can be received. Traffic data are from large zone FM reception zone. ECU provides data for VICS and to navigation ECU (18). ECU includes map data base (18a) and has connection to display a map and connection to search for route, and also includes microprocessor (18b) which extracts route data from database for display on screen (20). The system is characterised in that it has: storage means for storing traffic data connections; arithmetic unit that calculates traffic route data from a second connection which does not includes traffic congestion, this unit applying a weighting to traffic data from a first found connection in the data connections according to a different direction and a degree of separation between connections; and search unit which searches for a route towards destination using the two traffic data connections.