High‐efficiency broadband Doherty amplifier based on internal matching

Abstract

Abstract In this paper, a compact internally matched architecture of continuous class‐B/J Doherty power amplifier is studied. The influence of symmetric generalized combiner and postmatching network with harmonic control on the bandwidth and efficiency of Doherty power amplifier (DPA) is analyzed in detail. Based on the parameters obtained from theoretical analysis, a design method of internally matched continuous mode DPA (CM‐DPA) is proposed, and a broadband DPA with a size of 22.8 mm 24.5 mm was developed for experimental verification. The test structure shows that the maximum output power at saturation can reach 46.2 dBm. The efficiency of 6 dB back‐off is 58%–63.4%, with good consistency. In the reliability experiment, transistor and matching circuit of the CM‐DPA have a temperature below 100°C at saturation. The output power and efficiency tested at different temperatures (C, C, and C) show that the DPA has high reliability.