A W/F-Band Low-Noise Power Amplifier GaN MMIC with 3.5–5.5-dB Noise Figure and 22.8–24.3-dBm Pout

This paper presents an 80–122-GHz low-noise power amplifier (LNPA) monolithic microwave integrated circuit (MMIC) fabricated in a 70-nm gallium nitride (GaN) high-electron-mobility transistor (HEMT) technology. The LNPA MMIC contains a three-stage low-noise-optimized input stage and a balanced two-stage power-optimized output stage. From 80 to 122 GHz, the amplifier provides more than 24 dB of small-signal gain and a noise figure (NF) of 3.5–5.5 dB. For an extended upper band edge (87–124 GHz), the LNPA yields an NF of below 4 dB with an average value of 3.7 dB. At 1-dB gain compression, the MMIC exhibits an output power (Pout) in the range of 18.9–21.2 dBm. For a measured bandwidth of 80–122 GHz and an input power of 0 dBm, the amplifier yields a Pout of 22.8–24.3dBm with a corresponding power-added efficiency of 9.6–13.4%. With these performance parameters, the presented LNPA MMIC demonstrates the lowest GaN-based NF above 105 GHz, while providing a higher Pout than other LNAs at these frequencies.