Wide bandwidth inverse class F power amplifier with novel balun harmonic matching network

In this paper we present a novel wide bandwidth inverse class F power amplifier utilizing a broadside coupled Marchand balun to achieve optimal matching up to the third harmonic. This technique simultaneously provides improvement to power amplifier efficiency, saturation power, and linearity. A prototype power amplifier (PA) was constructed to verify this concept and its feasibility. The prototype PA uses two Gallium Nitride (GaN) pseudomorphic high electron mobility transistors (pHEMTs) and a multilayered, low loss substrate. The final power amplifier has a measured compressed output power greater than 40.5 dBm, a power added efficiency (PAE) greater than 55 %, a gain of 10.5 dB, and a fractional bandwidth of 40 % in X band.