A 135 GHz Differential Active Star Mixer in SiGe BiCMOS Technology

A 135 GHz
Gm
-boosted down-conversion active mixer adopting dual baluns has been developed in this work. Fabricated with a 0.18- μm SiGe BiCMOS technology, the mixer exhibits a differential-mode conversion gain of 11.5 dB at RF frequency of 134.7 GHz for a fixed LO frequency and power of 134 GHz and 10 dBm, respectively. The mixer also shows a
P
_{-1 dB}
of -20 dBm and LO-RF isolation of 31 dB. The entire circuit draws 1.3 mA from a 3 V supply. The fabricated mixer occupies 0.23 × 0.54 mm
²
of chip area excluding pad region.dual baluns