A Two-Stage Differential Structure TIA for 100-GHz Non-Contact Vital Sign Detection Radar

This paper presented a two-stage differential transimpedance amplifier (TIA) for 100-GHz non-contact vital sign detection Doppler radar. Following the passive down-conversion mixer, TIA convert the baseband current signal into the corresponding voltage signal. To achieve high gain and low supply voltage operation, a two-stage structure is used, in which the first-stage a folded cascode structure and the second-stage a common source (CS) structure. Implemented in 65nm CMOS process, the TIA provides 65 Ω input impedance and 75 dB Ω gain over 0.8 GHz BW-3dB, and it consumes 2.7 mA from a 1.2 V supply.