Digital Correlation Demodulator Design for RFID Reader Receiver

A high performance digital demodulator for RFID reader receiver is proposed. After carefully analyzing the characteristics of the received data, correlation operation is introduced into the demodulator to estimate the frequency of the received data and decode them. Simulation result indicates that this demodulator can work well under the 6dB input signal-to-noise ratio (SNR) with +/- 22% frequency deviation tolerance. FPGA implementation result shows that the communication distance between reader and tag can be extended to 5m above by the use of this demodulator.