Broadband Asymmetric GaAs MMIC Doherty Power Amplifiers With Simplified Peaking Matching Network and Output Capacitance Compensation

This letter proposes a compact asymmetric Doherty power amplifier (DPA) structure with a simplified peaking matching network (MN), and the output capacitance ( C_{\mathrm{OUT}}) of the peaking transistor is considered under different power states. The load-pull, including the MNs of carrier and peaking branch, is taken place to demonstrate the suggested scheme. For verification, a monolithic microwave integrated circuit (MMIC) DPA was designed and manufactured using a 0.25- \mu m GaAs process. The measurement results show that over a wideband of 4.3-6.0 GHz, the saturated output power is 29.4-30.4 dBm with a drain efficiency (DE) of 46.4%-57.1%. At 9-dB power back-off (PBO), the DE is 31%-43%.