RFID READER SUPPORTING DENSE MODE USING FFT ALGORITHM

摘要

Disclosed herein is a passive Radio Frequency Identification (RFID) reader supporting a dense mode using a Fast Fourier Transform (FFT). The RFID reader includes a modulator, a Radio Frequency (RF) transmitter, an RF receiver, a demodulator, a coupler, an FFT receiver, and a microcontroller. The modulator encodes and modulates interrogation signals, and converts resulting signals into analog signals. The RF transmitter performs up- conversion and power amplification on the analog signals, and radiates resulting signals. The RF receiver receives response signals, and performs frequency down-conversion and power amplification on the response signals. The demodulator converts the response signals into digital signals, and demodulates and decodes the digital signals. The coupler samples interrogation signals. The FFT receiver scans the frequency channels of the interrogation signals using an FFT algorithm. The microcontroller receives the results of the scanning, detects a currently unoccupied frequency channel, and communicates with a tag using the frequency channel.