RF Identification (RFID) Reader with Long Read Range in the UHF Band

In this paper, the design of a long read range UHF RFID reader using a novel carrier leakage suppression method is presented. We developed and demonstrated through experiment in the laboratory environment in the carrier-to-tag data ratio by more than 36 dBc in the UHF RFID band, which is consistent with our simulation results. When inserted between the reader antenna and a Class-1 RFID reader, measurements show that the reader can successfully demodulate the generated tag signal for a power level of 80 dBm, which corresponds to the backscattered power at 20 m distance. The read range of the reader with the proposed carrier leakage suppression front-end is verified again in a real environment. The measured read range is found to be greater than 20m for a commercial battery-assisted passive (BAP) tag.