A D-Band Low-Noise and High-Gain Receiver Front-End Adopting Gₘₐₓ-Driven Active Mixer

Phased-array systems are extensively utilized in wireless transmission and reception links operating at frequencies above 100 GHz to compensate for significant path loss. Regardless of beamforming architectures, the low-power implementation of a high-gain and low-noise receiver (RX) front-end (FE) plays a crucial role in large-scale RX arrays to maintain link margin. This article presents a 154 GHz low-power, high-gain, and low-noise CMOS RX FE adopting a proposed active mixer driven by a <tex-math notation="LaTeX">gₘ</tex-math> -stage based on a <tex-math notation="LaTeX">Gₘₐₓ</tex-math> -core. To ensure high-gain and low-noise characteristics, a two-stage low-noise amplifier (LNA) is implemented using the <tex-math notation="LaTeX">Gₘₐₓ</tex-math> gain boosting technique, while its first stage features a simultaneous noise-and input-matched <tex-math notation="LaTeX">Gₘₐₓ</tex-math> -core. The proposed active mixer consists of the <tex-math notation="LaTeX">Gₘₐₓ</tex-math> -based <tex-math notation="LaTeX">gₘ</tex-math> -stage and switching stages. The <tex-math notation="LaTeX">gₘ</tex-math> -stage driving the switching stage is realized using the <tex-math notation="LaTeX">Gₘₐₓ</tex-math> -core to enhance the gain and stability efficiently. To further increase the RX gain, a conjugate matching network is introduced between the <tex-math notation="LaTeX">gₘ</tex-math> -and switching stages, which is verified by a comprehensive analysis compared to previously reported techniques. Implemented in a 65-nm CMOS process, the proposed RX FE achieves a peak conversion gain of 28.5 dB and a minimum noise figure (NF) of 7.5 dB while operating under a low dc power of only 21.8 mW.