6.3 mW 94 GHz CMOS Down-Conversion Mixer With 11.6 dB Gain and 54 dB LO-RF Isolation

Abstract

A 94 GHz CMOS down-conversion mixer is reported. RF negative resistance compensation (NRC) technique, i.e., PMOS LC-oscillator-based RF transconductance (GM) stage load, is used to increase the output impedance and suppress the feedback capacitance C <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">gd</sub> of RF GM stage. As a result, conversion gain (CG), noise figure (NF) and LO-RF isolation of the mixer are enhanced. For frequencies of 80~110 GHz, the mixer consumes 6.3 mW and achieves excellent RF-port input reflection coefficient (S <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">11</sub> ) of -8.7~ -22 dB and LO-port input reflection coefficient (S <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">22</sub> ) of -10.3~-19.4 dB. In addition, the mixer achieves excellent CG of 4.1~11.6 dB, NF of 15.8~18.1 dB, and LO-RF isolation of 42.1~54 dB for frequencies of 80~110 GHz, one of the best CG, NF and LO-RF isolation results ever reported for a W-band CMOS down-conversion mixer.