A High-Gain D-Band LNA with Compact Gm-Boosting Core Based on Slow-Wave Feedback Achieving 6.1dB NF in 40nm CMOS

This study presents a 3-stage D-band low-noise amplifier (LNA) with novel feedback for wide-angle scannable array. The proposed slow-wave feedback provides the simultaneous broadband matching for noise and input impedance, and significantly enhances gain by parasitic elimination. Each common-source (CS) stage effectively leverages the gm-boosting core consisting slow-wave feedback for promoting the maximum available gain (Gma) and noise rejection. To demonstrate the feasibility of the proposed circuit configuration, the LNA is implemented in a 40 nm bulk CMOS process. The fabricated LNA achieves decent measured power gain of 18.4 dB, 3-dB bandwidth of 16.5 GHz from 131 to 147.5 GHz and minimum in-band noise figure (NF) of 6.1 dB with 17.1 mW power consumption. The core area of the LNA is 0.057 mm².