UHF RFID Reader Baseband Design And Research On Anti-Collision Algorithm

The development of networking technology makes radio frequency identification (RFID) are paid more and more attention by people either inside or outside the field where ultra-high frequency radio frequency identification system (UHF RFID) for its identification distance, reading and writing speed advantages, becomes a focus on the development of RFID. RFID system generally consists of tags, readers and the host, readers and tags use non-contact coupling mode of information delivery. Reader is an important part of the hardware of RFID system, which can be divided into antenna, RF transceiver, digital baseband and interface circuits, of which digital baseband is the core of the whole system, its functions and features directly affect the performance of the system.According to GB/T29768-2013, RFID 800/900MHz air interface protocol, this paper designs UHF reader digital baseband modules using FPGA, and the tag anti-collision algorithm is discussed. The main works of this paper are:1. Introduce and analyze physical layer parameters of GB/T29768-2013, RFID 800/900MHz air interface protocol, design the overall structure of the digital baseband system.2. For each module of baseband transmission link:CRC generation, TPP coding, waveform shaping, DSB-ASK/SSB-ASK modulation are parameterized and analyzed; simulate the waveform shaping signal by Simulink;simulate the DSB-ASK/SSB-ASK modulation through MATLAB, design and produce a raised cosine and a Hilbert filter coefficients.3. For each module of baseband receives link:channel filtering, ASK/PSK demodulation, preamble synchronization, FMO/Miller decoding, CRC check are parameterized and analyzed; simulate channel filtering, ASK/PSK demodulation through MATLAB, design and produce a band-pass filter coefficients.4. Under the environment of Xilinx ISE, using hardware language VerilogHDL as FPGA design entry, achieve the functions of all the modules above, and simulate module function through Isim and Modelsim; baseband codec design ideas and simulation results are given a more detailed analysis.5. Analyze several anti-collision algorithms qualitatively, and introduce DDS-BT anti-collision mechanism. Take the example of two tags collision to explain how the mechanism works.