A Broadband Asymmetrical GaN MMIC Doherty Power Amplifier with Compact Size for 5G Communications

This paper proposes a broadband asymmetrical monolithic microwave integrated circuit (MMIC) Doherty power amplifier (DPA) using 0.25-μm gallium-nitride process with compact chip size of 2.37 × 1.86 mm2 for 5G communication. It adopts an unequal Wilkinson’s divider ratio 2.5:1, where 71.5% the total is transferred to main higher gain. Different input matching networks are used offset phase difference while completing impedance conversion. design also applies novel topology solve problem large transformer (ITR) in conventional DPA, and it optimizes ITR from 4:1 2:1 wider band. Moreover, most components DPA including use lumped inductors capacitors instead long transmission line (TL) smaller space area. The whole designed simulated Agilent’s advanced system (ADS). small-signal gain 8–11 dB saturation output more than 39.5 dBm 800 MHz band 4.5 GHz 5.3 GHz. At 6-dB back-off, demonstrates 38–41.3% added efficiency (PAE), whereas 44–54% PAE achieved at power.