A High Gain Broadband LNA with Gate-Enhanced Triple-Coupled Transformer Feedforward Gm-Boosting Technique

This study presents a high gain broadband CMOS low noise amplifier (LNA) designed for frequency modulated continuous-wave (FMCW) radar applications in the 22–26 GHz K-band. A gate-enhanced triple-coupled transformer feedforward gm-boosting technique (GTTF-g
m
-boosting) is used for the two stage LNA in this study. The first stage of the LNA utilizes the proposed GTTF-g
m
-boosting technique to enhance gain and stability. A differential GTTF-g
m
-boosting cascode structure is proposed and implemented in the second stage to further increase gain. By employing 40-nm CMOS technology, the two-stage differential LNA achieves a high gain of 24 dB and a low noise figure (NF) of 3.7 dB across the 22- 26 GHz frequency range. The core area of LNA is only 0.17 mm
2
,