Design of inverse Class‐F power amplifier based on dual transmission line with 87.4% drain efficiency

Abstract

AbstractIn this paper, an inverse Class‐F power amplifier (PA) based on dual transmission line (DTL) is presented. The output matching network (OMN) with DTL has a simple and compact circuit topology compared with other harmonic‐tuned OMNs with open/short shunt stubs and provides up to 6th harmonic suppression. In addition, the DTL structure is equivalent to a quarter wavelength transformer for fundamental matching. A GaN HEMT is adopted to achieve high output power and high drain efficiency in the proposed inverse Class‐F PA. Finally, a 2.4 GHz inverse Class‐F PA is designed and fabricated. The experimental results show the highest drain efficiency of 87.4% in the operating frequency with the corresponding output power of 44.5 dBm, and adjacent channel power ratio (ACPR) of −50.8/‐51.6 dBc with digital predistortion technique (DPD) at 2.4 GHz.