High‐efficiency hybrid continuous mode power amplifier with input and output harmonic engineering

Abstract

This paper intensely studies the impact of the input nonlinearity caused by the transistor's feedback on the hybrid continuous class‐F power amplifier. The research extends the influence of input harmonics on class‐F power amplifiers to a more general form. Through waveform engineering, the impact of feedback is analyzed. By analyzing the change in cutoff angle caused by input nonlinearity, the change of the drain voltage and current waveforms of the hybrid continuous class‐F power amplifier can be obtained. The new drain voltage and current waveforms obtained from the analysis redefine the design space of source impedance and load impedance for the hybrid continuous class‐F power amplifier. By designing the corresponding input and output matching network, the second harmonic is suppressed, and finally, the hybrid continuous class‐F power amplifier achieves a high‐efficiency state. The research reveals that input harmonics also play an essential role in the design process of power amplifiers. A comparative experiment is designed to verify the theory. Simultaneously, a 1.6–2.8 GHz broadband hybrid continuous class‐F power amplifier is designed using this theory, with a saturation efficiency of more than 61.2% and a saturation power of more than 40.4 dBm.

A broadband high-efficiency GaN-based power amplifier using an improved continuous mode

“…It can be observed that the PA proposed here has the largest average efficiency, although the bandwidth of PAs in several works is wider than that presented in this work. Moreover, compared this work to those works [24][25][26][27] with similar frequency bands, it is clearer that the PA designed in this work is competitive in term of the average efficiency, which demonstrates that the expansion of the operating bandwidth in this paper does not come at the expense of efficiency.…”