Substrate integrated waveguide based class‐F power amplifier

Abstract This work outlines the design, implementation, and experimental results of a Class‐F power amplifier (PA) with a novel output matching topology by utilizing substrate integrated waveguide (SIW). The design methodology is first proposed with one highly integrated SIW matching structure. The impedances at fundamental, second harmonic and third harmonic frequencies are analysed to explain good impedance matching for the PA as well as the isolation mechanism of the direct current (DC) and radio frequency (RF). For demonstration, an S‐band 10‐W Class‐F PA is fabricated and tested. The simulation and measurement results agree very well with each other, which verifies the proposed technology of SIW output matching. To the authors’ knowledge, this is the first time to use a highly integrated SIW matching in Class‐F PA, which simplifies the output matching for third‐order harmonics and DC/RF isolation structures.