Ka-band 1 W GaN MMIC Power Amplifier Design

Abstract

Based on 0.1 µm GaN high electron mobility transistor (HEMT) process, a Ka-band 1-Watt monolithic microwave integrated circuit (MMIC) power amplifier with shunt negative feedback topology is designed and realized. By using the optimal impedance region concept in conjunction with matching compensation method, the performance degradation of power amplifier at the upper fundamental frequency caused by transistor gain roll-off characteristics can be alleviated. Bias branch circuitry incorporating stabilization networks and RF choke inductors used to replace lengthy microstrip lines are well integrated for compact size. Under 12 V supply in pulse mode, 34.1% peak power-added efficiency (PAE) at 29 GHz and over 20.5 dB small-signal gain, 29.8 - 30.3 dBm saturated output power (P sat ) across 26 - 30 GHz are obtained as shown in the experimental results.