Vehicle ID Transmitter in Service for Trip Time Data Collection System

Vehicular inductive radio transmitters mounted under the front license plate of taxicabs are now in practical service in Tokyo, Japan. The transmitter emits its ID number each time the vehicle passes over loop antennas buried under the road. The ID number is then transmitted via roadside equipments and leased telephone lines to a control center for calculation of point-to-point trip time on certain roads.

The vehicular units are designed so that a vehicular antenna and circuits are combined in one housing and are mounted with a metal attachment, using the front license plate bolts. In this article, the transmitter device and the management of the existing units (about 400) which have been in service is described.