Based Of Zigbee Technology Wireless Positioning System

With the developing of society, services based on location are more and more needed by people.The typical applications include Criminals Tracking, Missed People Searching, Visitor Navigation, and Car Park Tracking and so on. This paper, aiming at ZigBee network, investigates the outdoor wireless location techniques and implements a location and tracking system with the car used in the local car park area. This system is featured with low cost, low power, high reliability, and many other merits.The main contents of the study are as follows: first of all, we studied the current wireless location method, then analyzed benefits and disadvantages of current typical location systems and their using conditionings. Secondly, ZigBee technology based on the IEEE 802.15.4 protocol is researched, analysis on its topological structure has been done, and we chose a tree topology adapt to our system. Thirdly, analysis based on costs, precisions and probabilities has been done, RSSI-based measurements and trilateration method were chosen for this system. Besides, we used distance difference localization algorithm to improve the positioning precision, which present a higher precision.Finally, a location and tracking system for local car parking area is designed, which includes three parts, detecting at entrance, detecting occupany of vehicle berth, and car location and tracking.