This paper presents the design and experimental characterization of ultra-low-power Ka-band low-noise and medium-level amplifiers (LNAs/MLAs) for active antenna satellite communication systems. Fabricated in a 0.1-μm GaAs pHEMT process, the amplifiers achieve state-of-the-art performance at supply voltages as low as 1 V. The three-stage, source-degenerated LNA demonstrates a noise figure of 1.5 dB with 26 dB gain, while the MLA maintains a noise figure below 2.5 dB and 25 dB gain across the 27–31 GHz band. Both designs exhibit good linearity, with third-order intercept (TOI) points of +15 dBm (LNA) and +18 dBm (MLA) at the output section, and withstand repeated power sweeps up to +7 dBm without degradation. The MMICs feature a compact footprint of 2.3 × 1.4 mm2, enabling integration into densely packed arrays, and an ultra-low DC power consumption of 25 mW, which marks a tenfold improvement over conventional solutions. The lack of foundry models at low drain voltages was overcome through custom characterizations, with second-run designs achieving excellent agreement between simulations and measurements. Temperature testing confirmed stable performance from − 20 °C to +80 °C, with noise and gain variations comparable to higher-voltage counterparts. These results validate the feasibility of ultra-low-voltage amplifiers for next-generation high-throughput satellite payloads, balancing stringent noise, gain, and power constraints.