The Research And Design Of Wireless Position System Based On ZIGBEE

Global satellite positioning service has become an essential communication part in our daily life. However, due to the satellite is far away from the ground and the signal is too weak to penetrate the walls and other obstacles, leading to the current position services can not cover the basic room. With the improvement of living standards, the demand for precise positioning of individual is becoming higher, such as ambulance personnel need to know exactly which room and floor the wounded in; customers want to find the accurate location of the merchants and goods in large shopping mall; miners escape and rescue through the positioning system in underground and so on.The focus of this article is to achieve a practical indoor positioning system, with low cost, power consumption, high accuracy positioning, meanwhile to solve the problems may be encountered such as positioning range extension , signal optimization, data smoothing and other issues, to provide supplementary for wide-area positioning system and achieve blind-free positioning.This work has three main parts: First, according to the wireless real-time location system implementation principles, combined with the features of Zigbee wireless communication technology, analyzes the principles of positioning algorithms and engineering design; Secondly, the system design of the positioning network based on the Zigbee technology; Finally, design and implement a small Zigbee wireless real-time positioning system, and prove the feasibility of the system through the actual test results.To implement wireless location, we must find a distance-related system parameter first, in the Zigbee system is the received signal strength, that RSSI. This article studies the RSSI-based distance estimation methods, design the RSSI filtering algorithms with practice and analyze the algorithm method of constant values. In order to build a practical wireless positioning system, besides the realization of basic positioning algorithm, we need to optimize the positioning system. So, this article also studies some optimized algorithms used in practice, including signal optimization algorithm which is used to improve the accuracy of calculation, positioning range extension algorithms which provides the supplementary for positioning range and data smoothing algorithms which reduces data errors and increases the accuracy of positioning.In system design part, we mainly research the classification of topology network structure based on Zigbee technology and choose the most suitable topology structure for the positioning network. Meanwhile, we design the structure for the whole system of positioning network, including the definition of each part.For final verification, the project uses TI's integrated circuit chip CC2430/CC2431 designed and implemented a small set of wireless location system. It can calculate the positions of test nodes and real-time display the location of the test nodes with terminal tools. We use this positioning system to verify and pass the test.This study is only preliminary pilot study and the design of the positioning system can not be for the final commercial use. The article finally summarizes the work and the meanings of the research. We expect to provide a reference for future commercial use.