HIGHWAY VEHICLE IDENTIFICATION SYSTEM WITH HIGH GAIN ANTENNA

摘要

An apparatus for communicating with a transponder (10) carried by a vehicle moving along a multi-laned roadway (101, 103) comprising transmitter means (22) for producing a triggering signal, an antenna system (102) coupled to said transmitter means and being embedded in said multilane roadway, a receiver (18) coupled to said antenna system for monitoring transponder response electrical signals from said antenna system incorporating data related to the identity of the vehicle and correlating means to associate said lane of said multi-laned roadway with each identified vehicle. Said antenna system for mounting in a roadway comprises an electrically lossy material and has a reflector trough shield (123) filled with a solid dielectric (130). Said antenna, preferably comprised of coaxial cable, is positioned in the reflector trough, which prevents electromagnetic waves radiated by the antenna from being lost into the roadway.