Broadband Power Amplifier Employing Low-Pass Filtering-Based Matching Networks

Abstract

The pursuit of broadband, high-efficiency power amplifiers (PAs) remains a central challenge in next-generation wireless communication systems, where stringent requirements on output power, efficiency, and spectral integrity must be met simultaneously. This work presents the design methodology for a 10-W GaN HEMT-based broadband power amplifier (PA), employing low-pass filter (LPF)-inspired matching networks at both the input and output stages. By leveraging distributed transmission-line equivalents of lumped LPF prototypes, the proposed architecture achieves wideband impedance transformation while inherently suppressing higher-order harmonics. The proposed amplifier demonstrates stable operation from 0.6 to 3.2 GHz, with saturated output power maintained between 38 dBm and 41.4 dBm. The drain efficiency ranges from 54.4% to 82.07% across the band, confirming the effectiveness of the dual LPF-based matching strategy in enhancing harmonic rejection and preserving efficiency. The obtained results highlight that the proposed design's competitiveness in terms of bandwidth, efficiency, and power performance, underscoring its suitability for emerging broadband communication front-ends.