Efficiency Improvement of a 10 W GaN HEMT Power Amplifier Based on Hidden Markov Model Optimized by Particle Swarm Optimization Algorithm for Wireless Application

ABSTRACT Power amplifier design is an important topic in communication systems. Improving the efficiency of a power amplifier has long been a key interest to RF designers. In this paper, a 10 W GaN HEMT power amplifier is designed based on Hidden Markov Model optimized by Particle Swarm Optimization. The widths and lengths of the microstrip lines at the input and output of the matching networks in the proposed power amplifier are modelled using the Hidden Markov Model. For training the parameters of the Hidden Markov Model, the Particle Swarm Optimization algorithm is used. The power amplifier utilizes a 10 W GaN HEMT transistor (model CG2H40010F from Cree Corporation) and operates over a bandwidth of 2.5–3 GHz. At 2.98 GHz, the power amplifier achieves an output power of 39.3 dBm, a power‐added efficiency of 63.2%, and a gain of 15.3 dB. Across the entire bandwidth, it maintains output power above 38.18 dBm and gain above 14.2 dB, with power‐added efficiency exceeding 50% between 2.8 and 3 GHz. These results highlight the effectiveness of the HMM‐PSO approach in enhancing the performance of the proposed GaN HEMT power amplifier.