According to phenomenon of disturbance of Earth’s magnetic field caused by vehicle passing

a kind of vehicle detector which is based on AMR sensor and Zig Bee technology is designed to place in traffic intersection

and the vehicle detector has features of easy installation and high reliability

etc. Principle of magnetic resistance sensor detection

design of measuring circuit

software and hardware design of wireless transceiver module and experimental results are given. It is proved by experiment that the vehicle detector can accurately and get all kinds of traffic data including flow of vehicles

vehicle speed

vehicle density and headway

share

etc in real-time

it is one of the most important traffic data collection equipment in intelligent traffic system（ ITS）.