A new ultrahigh frequency radio frequency identification (UHF RFID) reader’s front-end circuit which is based on zero-IF, single
antenna structure and composed of discrete components has been designed. The proposed design brings a significant improvement
of the reading performance by adopting a carrier leakage suppression (CLS) circuit instead of a circulator which is utilized by most
of the conventional RF front-end circuit. Experimental results show that the proposed design improves both the sensitivity and
detection range compared to the conventional designs.