Design of Broadband Highly Efficient Power Amplifier Based on Low‐Pass Filtering Network With Periodic Structure

ABSTRACT In this paper, a broadband high‐efficiency power amplifier (PA) is designed by using an easily implementable low‐pass filtering network with periodic structure as the output matching circuit to achieve bandwidth expansion of the PA. The proposed periodic structure is based on right‐handed T‐type basic cells, which can achieve wideband filtering responses. In addition, the load design space of the extended continuous Class‐F mode is combined as the target impedance to achieve an efficiency improvement in bandwidth PAs. For verification, a broadband highly efficient PA across 0.6–3.6 GHz with a relative bandwidth of 143% is designed, fabricated, and measured. The test results have shown a drain efficiency of 60.8%–70.4% and gain of 8.5–11.9 dB with a saturation output power under 3‐dB gain compression of 38.5–41.9 dBm.