Outdoor Personnel Positioning System Research And Design Based On GPS And Wireless Sensor Networks

In order to avoid detainees' escape during medical treatment or labor, the requirements of accurate positioning, trajectory information transmission and visual management are increased greatly with the development of public security information construction. In a fixed detection region, Wireless Sensor Network (WSN) can deal with all kinds of data in a collaborative way. Global Position System (GPS), as one of the core technology of WSN, is a prerequisite for recognition, location and tracking. In order to satisfy the demands of public security, position and track detainees in outdoor, this paper present an outdoor personnel positioning method and data reliable transmission algorithm. The outdoor personnel positioning system based on GPS and WSN has been designed, which has the practical significance in prison management.This work was partially supported by the National Natural Science Foundation of China, Science and Technology Department of Zhejiang Province, and Cultivation Fund Program for Excellent Dissertation in Zhejiang Sci-Tech University. The main research contents and achievements are as follows:(1) Review the background and development of GPS and WSN both in China and abroad. The characteristics of outdoor activity and business needs in the detention center are analyzed. The overall architecture of the regulation positioning system is proposed.(2) The outdoor personnel positioning system based on GPS and WSN has been designed. It is composed of electronic wristbands (used for detainees), handsets (used for supervisors) and monitoring software of the host computer. Wristbands will be supervised by handsets. And all data will be uploaded to the monitoring software. So information inquiry and path tracking can be achieved.(3) Long time delay and data packet dropout appeared in the WSN is studied. According to the principle of separation, the state observation predictor and the state feedback controller are designed separately. Based on the T-S model, a predictive compensation scheme including timer and counter for wireless networked system with long time delay and data packet dropout is proposed. And the simulation result verifies the effectiveness of the method to improve the reliable data transmission.(4) Self-prepared packet transport protocol is presented. And command response and data transmission are implemented between wristbands and handsets. What's more, in order to improve the accuracy of positioning, equal weighed mid-smoothing method is applied in error correction. And precise latitude and longitude distance algorithm is introduced to work out the distance between wristbands and handsets. Therefore, whether detainees are within the scope of the regulation or not can be judged immediately.(5) A prototype system is built. Then functional and performance testing is conducted. The functions of fixed and moving groups positioning, path tracing and monitoring are implemented. The system is characterized by high precision, exact location and overall functions. It can effectively prevent detainees to flee and chase criminals accurately. As a result, it has very wide popularization and application prospects in the detention center.