Design of the TDOA Positioning System Based on ZigBee Technology

The method based on time difference of arrival(TDOA) in the high-precision wireless sensor network positioning system has received more and more research attention.A set of wireless communication nodes based on ZigBee protocol is designed to form a hardware platform by adding ultrasonic ranging devices.The characteristics of beacon and common nodes are analyzed,then a positioning mechanism based on event-driven is proposed which can not only ensure the system a high response speed but also a considerable reduction in the power consumption of the system.It can solve the problems of energy collisions and signal crosstalk in the air as well.Finally,corrections to the ranging errors are made based on large amounts of experimental analysis.As a result,the influence of ranging errors is largely reduced and the positioning precision is improved.