Low-Noise Power-Amplifier MMICs for the WR4.3 and WR3.4 Bands in a 35-nm Gate-Length InGaAs mHEMT Technology

This letter presents two distributed low-noise power-amplifier (LNPA) monolithic microwave integrated circuits (MMICs). The two amplifiers (DA1 and DA2) target the WR4.3 (170–260 GHz) and WR3.4 bands (220–330 GHz) as a minimum operating bandwidth (BW). The MMICs are realized in the Fraunhofer IAF 35-nm InGaAs mHEMT technology. Both amplifiers yield a small-signal gain of more than 20 dB from 110 GHz up to the corresponding upper band edges (265 and 335 GHz) and an average noise figure (NF) of 4.5 dB (110–216 GHz). Furthermore, DA1 delivers a saturated output power ( ${P}_{\mathrm{ sat}}$ ) of 12.4–15.2 dBm with a power-added efficiency (PAE) of 3.4%–6.2% (160–255 GHz). DA2 exhibits a ${P}_{\mathrm{ sat}}$ of 10–14.5 dBm (210–335 GHz). To the best of the authors’ knowledge, DA1 and DA2 present the best NF and ${P}_{\mathrm{ sat}}$ over the full WR4.3 and WR3.4 bands, respectively.