Heinz, FelixFelixHeinzThome, FabianFabianThomeLeuther, ArnulfArnulfLeuther2025-07-252025-07-252025https://publica.fraunhofer.de/handle/publica/48995610.1109/IMS40360.2025.11103921In this paper, two low-noise-amplifier (LNA) monolithic microwave integrated circuits (MMICs) in a 50-nm metamorphic high-electron-mobility-transistor (mHEMT) technology extending the D-band (110-170GHz) are demonstrated. The optimization of the matching networks in D-band for lowest noise and high gain is discussed. LNA 1 utilizes a grounded co-planar waveguide environment with 30μ m ground-to-ground spacing, while LNA 2 is investigating how the noise performance can be improved by using a lower loss input matching network with 50μ m ground-to-ground spacing. LNA 1 achieves an average in-band gain of 27.7 dB over a broad bandwidth of 96-168GHz, with an average noise temperature of 343 K (3.4 dB noise figure). LNA 2 operates between 98−170GHz with an average small-signal gain of 25.4 dB and an measured average noise temperature of 325 K (3.2 dB) between 107-170GHz. To the best of the authors' knowledge, this is the lowest noise performance demonstrated over the full D-band by an LNA at room temperature.enHigh-electron-mobility transistors (HEMTs)low-noise amplifiers (LNAs)metamorphic HEMTs (mHEMTs)microwave monolithic integrated circuits (MMICs)millimeter-wave (mmW)D-bandconference paper