Over Second Octave Power Amplifier Design Based on Resistive–Resistive Series of Continuous Class-F/F−1 Modes

This letter presents a novel methodology for resistive-resistive series of continuous class-F/F
^-1
modes (Res.-Res. SCF/F
^-1
Ms) power amplifier (PA) design. The bandwidth is expanded by designing the lower band with resistive secondand third-harmonic impedances and the upper band with resistive second-harmonic impedance and reactive thirdharmonic impedance using a waveform engineering method. Mathematical derivation of the methodology is described in detail. The proposed design is experimentally verified using a Res.-Res. SCF/F
^-1
Ms PA operating across 0.4-2.3 GHz with 62.3%-80.5% drain efficiency and 39-42 dBm output power.