A 0.5-2.6 GHz GaN Power Amplifier Based on Filter Synthesis and Multi-Frequency Impedance Matching

This paper presents a straightforward design approach based on the synthesis of low-pass filters and multi-frequency impedance matching to achieve a high-efficiency power amplifier (PA) with more than an octave bandwidth using a 10 W gallium nitride (GaN) device. Using a four-stage Chebyshev matching structure, a matching network from a fixed real impedance to a set of frequency-dependent complex impedances has been optimized and implemented. Both simulation and experimental results show that a broadband PA is realized from 0.5 to 2.6 GHz with a measured drain efficiency (DE) of 60%-68.4% at 38.9-42.3 dBm saturated output power. These results validate the feasibility of the design methodology and confirm the consistency between simulated and measured performance.