Ka-band GaAs MMIC Driver Amplifier Design

Ka-band three-stage MMIC driver amplifier with a Y-junction combiner is presented based on 0.15 μm GaAs pseudomorphic high electron mobility transistor (pHEMT) process. The compensated matching method and parallel-stub tuning technique are utilized to flatten the gain response. Bias branch circuitry in combination with stabilization networks is integrated for compact size. Under 5 V supply, over 22 dB small-signal gain, 32.8% peak power-added efficiency, and 25.6 - 26.3 dBm saturated output power across 25 - 29 GHz are obtained as shown in the experimental results.