A K alpha-band three-stage monolithic microwave integrated circuit (MMIC) low-noise amplifier using source inductors with different values for each stage has been developed for use in active phased-array receiver modules, The three-stage MMIC low-noise amplifier with 0.15 x 120 mu m(2) AlGaAs/InGaAs pHEMT's has achieved a noise figure of 1.6 dB, a gain of 22.8 dB, an input return loss of 29 dB, and an output return loss of 24 dB at 28 GHz by optimizing the values of source inductors for each stage. The minimum noise figure was 1.3 dB at 30 GHz.