I/Q mismatch compensation in a 90nm low-IF CMOS receiver

Abstract

An I/Q mismatch compensation circuit for a low-IF GSM receiver implemented in a 90nm CMOS process is presented. A single-tap adaptive decorrelation technique is used with L/sub 1/-norm inverse power measurement and gear-shifting circuits. An image rejection ratio in excess of 50dB is achieved allowing the receiver to use IF frequencies higher than half of the channel bandwidth.