CMOS 138 GHz low-power active mixer with branch-line coupler

Abstract

A 138 GHz down-conversion mixer with a branch-line coupler has been developed based on a 90 nm CMOS technology. The fabricated mixer shows a differential conversion gain of 3.7 dB with the mixer core drawing a current 0.66 mA from a 1.2 V supply. The 1 dB gain compression point is estimated to be larger than -6 dBm. The mixer occupies 0.61 x 0.62 mm(2) of chip area excluding pads.