An LPTV Noise Cancellation Technique for a 0.9-V Filtering-by-Aliasing Receiver Front-End with >67-dB Stopband Rejection

A linear periodically time-varying (LPTV) noise cancellation technique for filtering-by-aliasing (FA) receivers is presented in this paper. Fabricated in a 28-nm CMOS process, it improves the noise Figure (NF) by about 3 dB while achieving over 67-dB stopband rejection with a transition bandwidth of only four times the RF BW. A minimum in-band NF of 3.2 dB is demonstrated. With an upfront -path filter to further enhance the linearity, the measured out-of-band IIP₃ is + 18 dBm and the blocker 1-dB compression point is + 9 dBm. Operating under a 0.9V supply, it consumes 61-mW power at 500-MHz LO.