Design And Implementation Of Indoor Positioning System Based On RFID

With the development of science and technology, positioning systems are widely used in life, such as global positioning system(GPS). At present, as the signal strength becomes weak for indoor environment, the position technology which is used for the outdoor environment is not fit for positioning system for indoor environment. So it is important to study the indoor positioning system with high precision and low cost, such as the rescue in natural disasters, browsing the exhibits, etc.This paper will focus on the indoor wireless positioning system in which the persons or things to be positioned can't send request for position. By taking account of the properties and requirements of the indoor wireless positioning system, we study the positioning algorithm based on the strength of the received signal, and realize the indoor positioning system based on radio frequency identification devices(RFID). The paper analyzes the localization algorithms which have been used in indoor positioning systems widely. As the model is not accurate between the strength of signal and the positioning distance, a new model will be built based on the BP neural network. At the meantime, in order to improve the accuracy of BP neural network algorithm, the genetic algorithm is used to optimize the BP neural network system. Considering that the indoor environment may exist some factors which are unsure, we propose a region determination mechanism(RDM). Firstly, the coverage of the anchor should be determined by the referenced tags of which the coordinate is known, secondly, calculate the actual coordinate of the positioned node which is in the coverage of the anchors.Programming to realize the human-computer interactive which is the important module of the indoor positioning system based on RFID. The hardware of the system can be control by the human-computer interactive, and the actual coordinate of the positioned node can be shown. Design the RFID read-write circuit based on PR9000 chip peripheral, and build the experimental platform of indoor positioning system to verify the locating algorithm.The indoor positioning system based on RFID can be applied for all kinds of aspects in the live, such as logistics tracking, warehouse management.