Research, Simulation And Implementation Of RFID System’s Data Coding Method

Radio frequency identification(RFID) technology is a kind of automatic identification system rising in the 1990’s which has many advantages, such as non-contact recognition, high accuracy and safety, resistance to bad environment and fast identification of multiple objects. It has already formed an Internet of Things industry which integrated computer communication, network technology, RFID and sensor technology. As a new and widely used technology, RFID technology plays an important role in such aspects as economy, society and national defense.In this thesis, it first studied the basic theories of data transmission in the RFID system which involved in channel coding and decoding, error detection and correction. It also studied commonly-used coding methods in RFID data transmission system, such as Manchester code, unipolar return to zero(unipolar RZ) code, differential bi-phase(DBP) code and Miller code, and made comparisons in them using Matlab Simulink software to build simulation module, and made simulation analysis. It also made function and timing simulation with above commonly-used transfer coding circuit using programmable device development platform Foundation, and then downloaded them to the programmable logic devices XC95108PC84 and connected to hardware circuit, used the oscilloscope to test the result of the encoder and decoder. Secondly, the research and simulation analysis were carried out on the anti-interference ability of channel coding and got the effective method in actual application. It also studied several common error control coding methods, and simulated the checking feature of CRC which was commonly used in RFID system. Finally, It combined all above modules to make integrated simulation with data transmission of RFID system. Through the analysis of relationship between channel coding method, data checking method, system error rate and channel SNR, it obtained a result of common coding method and transmission channel adaptation ability. It also concluded that the practical application should be preferred in Manchester code or andunipolar RZ code.