Wireless vehicle detector using a magneto-resistive sensor

초록

This paper proposes a wireless vehicle detector with anisotropic magneto-resistive (AMR) sensors and addresses some field test results to show the performance of the detector. The detector consists of two AMR sensors and mechanical and electronic apparatuses. Vehicle speeds are calculated by using two AMR sensors fixed on a board, with constant distance. The speed of a vehicle is calculated by dividing the distance between the two sensors by the time difference between the two output signals from each sensor, captured sequentially while the vehicle is passing over the sensors. To verify the performance of the detector, vehicle speeds and volumes on a local highway were measured and compared with the reference measurements obtained from a traffic camera, both in a free running and a highly congested traffic.