The Research And Implementation Of Signal Monitor Algorithm In RFID Communications

As a new technology of Auto-ID, RFID can be widely used in military and civil fields. The most significant feature of RFID is that it can contactlessly communicate to reach the goal of Auto-ID by radio frequency. The design of multi-band adaptive RFID reader is a interested field of the reader's research. The multi-band adaptive reader's design used soft defined radio structure is a feasible choice.Based on the analysis of invariant features in cumulant domain of radio frequency identification, The main works investigated in this dissertation can be summarized as follows: a review of the communication technologies of radio frequency identification, a study of the multi-band RFID reader structure used soft defined radio , a study about the RFID hardware interface used soft defined radio, a study about signal monitor module in multi-band RFID reader, a study about signal monitor algorithm in soft defined radio reader. a study of parameter estimation algorithm and implementation about three essential elements of microwave frequency signals: the carrier frequency, symbol speed and modulation format.The first, the function of the signal monitor module in soft radio is discussed. Based on this discussion, the carrier frequency, symbol speed and modulation format are the three essential elements of the RFID signals. The algorithm of signal zero-crossing estimation are used to estimate the carrier frequentcy. The algorithm of haar wavelet is used to estimate the symbol speed. The BP neural network algorithm is designed as modulation classification. Computer simulation of signal monitor algorithm are carried out to measure the performance of the algorithm.