WIRELESS SENSOR SYSTEM FOR TRAFFIC SIGNAL CONTROL

摘要

Systems and methods are provided for wireless signal communication among remotely located system components to monitor ground vehicle traffic. In one embodiment, a road sensor (110) passively senses an ambient magnetic field level. The road sensor (110) senses a change from the ambient magnetic field level to a magnetic field level corresponding to presence of a vehicle in the vicinity of the road sensor (110). A master transceiver (112) sends a poll signal to, and receives a traffic state signal from, the road sensor (110) via a wireless signal communication link. A spread spectrum communication subsystem (514, 614) provides the wireless signal communication link and operates on a changing frequency to which the road sensor (110) is synchronized. In one embodiment, a spread spectrum compatible repeater transceiver (114) extends the range between the master transceiver (112) and the road sensor (110).