A UHF mobile single chip RFID reader is implemented in 0.18 mum CMOS process. Developed IC achieves DA output power of 3 dBm, OIP3 of 14.8 dBm, phase noise of -100 dBc/Hz at 100 kHz offset, noise figure of 35.5 dB for talk mode, 6.2 dB for listen before talk (LBT) mode, and current consumption of 108 mA from a 1.8 V supply. With an external PA, Tx output generates output power of 27 dBm with OIP3 of 42.5 dBm. A leakage signal cancellation scheme is employed to suppress inevitable Tx leakage into Rx input. At a distance of 90 cm between antenna and tag the average recognition ratio is increased from 0% to 42.8% by the leakage canceller.