Design of an Extended Continuous-Mode Class-GF Power Amplifier With Multioctave Bandwidth

An extended version of the continuous-mode Class-GF power amplifier (PA) design theory is first proposed in this letter by analyzing the impact of input voltage waveform alterations caused by input nonlinearity on the drain current waveform. Then, a novel impedance design space is explored under the extended continuous-mode drain voltage waveform. Thereafter, a multioctave, high-efficiency extended continuous Class-GF (ECCGF) PA component was implemented, fabricated, and measured with a 10-W GaN HEMT device over a 150% bandwidth from 0.4 to 2.8 GHz. The test result shows that the 39–42-dBm output power, 63%–73.2% drain efficiency (DE), and 9–12-dB gain are achieved in the target band.