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Abstract: For a frequency‐division duplex (FDD) wide‐band code‐division multiple‐access (WCDMA) system, transmit (TX) signal leakage at the receiver input degrades the receiver performance. To cancel this TX leakage, a frequency selective feedback was previously proposed, but it had an unpredictable feedback loop characteristic due to the uncertainty of the duplexer impedance. This paper presents a new method to achieve TX leakage cancellation regardless of the duplexer impedance. In addition, a local oscillator (LO) phase shift technique is proposed to apply this method for multi‐band. A receiver adopting these proposed techniques is implemented using a 0.18‐μm CMOS process to prove the concept. The measured TX attenuations of the high‐ and low‐band are 17‐dB and 20‐dB, respectively, and the measured noise Figure (NF) degradations of the high‐ and low‐band are 0.6‐dB and 0.5‐dB, respectively. The measurement results demonstrate effectiveness of the proposed techniques. [ABSTRACT FROM AUTHOR]