volume | PIER Journals

Abstract

This paper proposes a dual-band class-F^-1 high-efficiency power amplifier with an integrated structure for harmonic suppression and fundamental matching. The fundamental matching network employed a dual-frequency coupler with open branches. This structure is partially reused for third-harmonic control by leveraging two open branches and two branch lines. By adjusting the characteristic impedance of the quarter-wavelength transmission line, the third-harmonic impedance is adjusted to a short circuit at both fundamental frequencies at the drain of the power amplifier. The second-harmonic control network consists of a quarter-wavelength open stub and a drain bias line loaded with a double spiral defected ground structure (DGS), which controls the second-harmonic impedance to an open circuit state at the drain, satisfying the class F^-1 harmonic conditions. A dual-band high-efficiency class F^-1 power amplifier operating at 2.6 GHz/3.4 GHz is designed and fabricated. The measured results show drain efficiencies of 73.5% and 74.3% at 2.6 GHz/3.4 GHz, with output power exceeding 40 dBm and gain above 10 dB.

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Dr. Wen Huang

Dr. Junhao Zhao

Dr. Jiang Liu

Professor Honggang Hao