Design of a Novel Wideband High Efficiency CCF PA

Abstract

In this article, a novel approach for the design of broadband high-efficiency power amplifiers (BHPAs) is presented. The method is to simplify the process of synthesizing a wideband output matching network by realizing harmonic tuning and fundamental matching separately. First, the second and third harmonic load impedances are calculated based on the theory of Continuous Class-F Mode. Then, a novel wideband harmonic-suppressing network is obtained by using microstrip radial stubs which is not affected by the adjacent fundamental matching circuit. The proposed PA using a 10-W Cree GaN HEMT device achieves a measured result of a fractional bandwidth of 30.4% from 1.95 to 2.65 GHz, with 60.9–81.6% drain efficiency, 60–79.9% PAE and 39.7–41.7 dBm output power throughout the operating band. As shown in the design process, simulated analyses and measured results, the proposed idea makes the design of the harmonic load network much easier and more accurate. It is generally more feasible, compared with some of the existing methods which are difficult to realize the fundamental and harmonic wave controlling at the same time, especially at higher frequencies. And this method can be widely applied in the BHPA design and modern wireless communication systems.