An LO Leakage Suppression Technique for Blocker-Tolerant Wideband Receivers With High-Q Selectivity at RF Input

A wideband blocker-tolerant receiver (RX) employing a novel local oscillator (LO) leakage suppression technique is presented. At the core of this RX, lies a bandpass common-gate structure that realizes high-Q selectivity directly at RF input while greatly suppressing LO leakage coupled to the RX input. The RX prototype, manufactured in a 45-nm CMOS SOI process, achieves wideband tunable high-Q selectivity from 0.2 to 2 GHz, while the LO leakage stays well below -80 dBm. The noise figure is better than 2.5 dB and degrades to 6.7 dB with a 0-dBm blocker at 80-MHz offset frequency. The measured out-of-band IIP2 and IIP3 at 100-MHz offset frequency are +60 and +14 dBm, respectively. The RX consumes up to 95 mW of total power at 2 GHz and occupies 1.05 mm
²
of active area.