A Highly Extended High-Efficiency Range Class-F–C Doherty Power Amplifier

Abstract

This paper presents a new extended high-efficiency-range Doherty power amplifier (DPA) with a main and only a single auxiliary amplifier. In order to extend the output high-efficiency range with a high-efficiency level, asymmetrical cells are employed as the main and auxiliary amplifiers in class-F and class-C complex combining load (CCL) methodology, respectively. To verify the proposed methodology, a DPA with 12-dB output back-off (OBO) is designed and fabricated for wideband code division multiple access (WCDMA) applications. Large-signal continuous-wave measurement results show the power gain of about 11[Formula: see text]dB with a drain efficiency of 59.9% at 12[Formula: see text]dB of OBO. A two-tone test exhibits a third-order intermodulation distortion (IMD) of lower than [Formula: see text][Formula: see text]dBc. Modulated wave measurements show over 55% of average drain efficiency and an adjacent channel leakage power ratio (ACLR) of lower than [Formula: see text][Formula: see text]dBc at an output power level of 31.5[Formula: see text]dBm.