Wideband cancellation of second order intermodulation distortions in a 60GHz zero-IF mixer

The 1 GHz target IF bandwidth of 60 GHz zero-IF mixers makes conventional single- and double-parameter tuning methods ineffective for suppression of second-order intermodulation distortions across the whole IF band. In this paper a three-dimensional circuit parameter tuning method is used to address this problem. Output resistance, output capacitance, and gate biasing of the switching pairs are three parameters chosen for tuning. The mixer is designed and fabricated in CMOS 45 nm technology. Measurement results show that the IMD2 tones across the whole 1 GHz IF band can be suppressed simultaneously to within the noise level. The measured power conversion gain, IIP3 and typical corrected IIP2 of the mixer are 7 dB, -7 dBm and 27 dBm, respectively.