A 140 GHz SiGe Power Amplifier with >12.5 dBm P1dB and >8% PAE for Phased Array Systems in 6G Communication

This paper presents a 140 GHz power amplifier for phased array systems in 6G communication. The power amplifier is designed using 130nm SiGe process (SG13G2) from IHP foundry. To compensate for low gain of devices at Sub-THz/THz frequencies, the proposed single-ended two-stage power amplifier utilizes cascode topology for each stage. Additionally, the proposed work carefully analyses the impact of interconnects/parasitic on device performance and subsequently minimizes the interconnect/parasitic losses to achieve state-of-art power added efficiency of 8-15% and gain of $\gt20 \mathrm{~dB}$ in two stages. The power amplifier shows output P1dB of $\gt12.5 \mathrm{dBm}$ from $133-153 \mathrm{GHz}$ with corresponding PAE of about 10 %. Achieved saturated power (Psat) is $\gt14.2 \mathrm{dBm}$ with corresponding PAE of about 12 % over this band.