Research Of Passive RFID Indoor Location Algorithm Based On RSSI

In recent years, with the rapid development of the Internet of things and the rapid increase in data services, the demand of indoor positioning is growing day by day. RFID technology is a relatively new technology, its advantages including non-line, non-contact, low price and so on, making it a preferred indoor positioning. Especially, the passive RFID positioning technology is more and more attracting researchers attention. However, since the passive RFID location system RSSI is less than the active system, the accuracy of the positioning system is affected. Therefore, it is important to design a high-precision passive RFID indoor positioning algorithm.Firstly, this thesis describes the background knowledge, including RFID appliccations and its develepment trend as well as the common indoor positioning technology. Secondly, this thesis introduces the RFID technology and the indoor positiong methods: AOA, TOA, TDOA and RSSI. Then, this thesis describes three RFID indoor positioning algorithms based on RSSI.In order to improve passive RFID positioning systems accuracy, this thesis proposes a hybrid algorithm based on the nearest neighbor algorithm and the triangulation algorithm, which is combined by a weighted formula. Meanwhile, improving the reader layout makes the hybrid algorithm better result.Simulation results show that: compared with the nearest neighbor algorithm, the hybrid algorithm positioning precision is increased by 68.92% averagely; also, compared with the triangulation algorithm, the hybrid algorithm positioning precision is averagely increased by 63.04%. The hybrid algorithm improves the accuracy of the positioning system greatly.