Two-stage Class F-C Power Amplifier with an Optimum 2nd Harmonic Control at the Power Stage Input

This paper presents a two stage Class F-C power amplifier working at S-band. It achieves PAE larger than 60% and an output power of 36 dBm over frequency range 2.27 GHz to 2.44 GHz. The harmonic injection approach is used into the design. By introducing an additional driver stage and a proper inter-stage matching network, the optimum ratio between the 2nd harmonic and the fundamental one is obtained at the gate of power stage, in order to realize a Class F-C PA. The design procedure and the feasibility of harmonic manipulation at the input of the relevant stage is also presented in this paper.