Design Of Wireless Vehicle Detecting System Based On Three-axis GMR Sensor

The research is design of wireless vehicle detecting system based on three-axis GMRsensor, which consists of wireless parking detection based on three-axis GMR sensor in theparking lot and wireless vehicle detection based on three-axis GMR sensor on the road.The major study is design of wireless parking detecting system based on three-axis GMRsensor in order to solve the difficult parking problems in city, which is a combination of GMRsensor and wireless sensor network technology of ZigBee.Wireless parking detecting system has coordinator node, router node and data collectionnode. Coordinator node is responsible for formation of network. Router node achieves routingfunction. Data collection node performs data collection.Wireless parking detecting system’s hardware includes data collection module, powermanagement module and RF transceiver module. Data collection module is responsible forsignal acquisition, amplification and filtering. The three-axis GMR sensor achieves the signalacquisition, which has the right harsh environmental adaptability, high sensitivity and longlife advantages. In order to complete low power, power management module uses polymerlithium battery. Its advantages have a good safety, thin, light, weight, large capacity and smallinternal resistance. CC2530is TI’s standard for IEEE802.15.4and ZigBee solution. The mainpart of CC2530is RF transceiver module.Wireless parking detecting system’s software includes protocol stack of ZStack, wirelessparking detection’s algorithm and parking information’s display. ZStack is composed of somerelated operations. The subject achieves data acquisition, serial communication, low powerconsumption and routing functions through ZStack. Wireless parking detection’s algorithmfilters out random noise signal and background signal to extract parking signal. Parkinginformation is displayed through software of LabVIEW to achieve.In the parking lot, wireless parking detecting system has some experiments to measurethe magnetic field’s distribution of different orientation spaces, and map the magnetic field’sdistribution in different locations. The results indicate that the wireless parking detectingsystem has low cost, low power consumption, small size and good performance. It can bewidely used in the management of parking lot.