Research On Radio Frequency Identification Technology And Application In Public Traffic Dispatch System

RFID (Radio Frequency Identification, RFID) technology is a new type of automatic identification technology. It developed very rapidly in recent years, and has been widely used in many applications.But there are some key issues in RFID techology promotion process, such as it is difficult to determine the resonant frequency in design of UHF RFID reader microstrip antenna, and it can not identify the multiple collision tags when they simultaneously come into the reader's area.These problems limited the further application of RFID technology.This paper discussed the significance of RFID technology and the basic theory, and analysised the intelligent algorithm's application in the modeling of microstrip antenna. Furthermore the tag anti-collision solution technology has been illustrated. Finally, the public transport scheduling system based on UHF RFID technology has been designed.Firstly, the intelligent algorithm in modeling of microstrip antenna RFID reader has been studied and a modified particle swarm algorithm trained neural network structure used in the antenna resonant frequency of the antenna model has been proposed.The structure and properties of the antenna is a much more complicated nonlinear system which is hard to model mathematically accurately. The basic BP algorithm, GA algorithm and the improved PSO algorithm to train neural network frequency model has been researched in order to solve premature convergence of the network, the network and low accuracy problem.The experiment results showed that PSO neural network could establish an accurate, complete modele between the resonant frequency and structure of microstrip antenna,which could achieve the design of the reader antenna rapidly.Secondly, multi-tags collision problem had been studied, and a quick method to estimate the proposed tags' number and a novel anti-collision algorithm based on reverse mechanism had been proposed.In this paper, the curve between the number of collisions and the average collision probability has been estimated which was based on the experiment data. The curve was replaced by the simplified line, and then the recognition speed had been increased. By analyzing the relationship between the different frame sizes, the frame length adjustment method was improved.In the binary search algorithm, the pretreatment mechanism had been proposed to reduce the communication reader and tag data. The simulation results demonstrated the improved method could effectively reduce the recognition time and improve recognition efficiency.Finally, combining the characteristics of public transport, a novel intelligent transportation scheduling system based on ultra-high frequency RFID technology had been proposed. And a dual-frequency RFID reader which has 13.56MHz and UHF 915MHz was designed and realized. Actual tests showed that the dual frequency points RFID readers could simultaneously achieve function of read-write card function both in high frequency and ultra high frequency, and resonant frequency of microstrip antenna could meet the real requirements.At the same time, and improved identification tag anti-collision algorithm is faster.