A 1.1GHz bandwidth, 46%–62% efficiency Continuous Mode Doherty Power Amplifier

In this paper, a novel technique is proposed to improve Doherty Power Amplifiers' (DPAs') bandwidth and efficiency by manipulating harmonic components to reshape current and voltage waveforms over a continuous bandwidth. Such operation creates a series of continuous high efficiency modes at each frequency over the band, which is referred as Continuous Mode Doherty Power Amplifier (C-DPA) in this paper. Based on the proposed technique, a 30-Watts broadband C-DPA is designed over the entire mainstream communication frequency band 1.65-2.75GHz. Using a 20MHz, 7.5dB PAPR LTE signal, the fabricated DPA is measured and linearized. According to the measured results, the designed DPA exhibits 46%-62% modulated efficiency over the designed 1.1GHz frequency range while maintaining Adjacent Channel Power Ratio (ACPR) below -45dBc. To the best of the authors' knowledge, this is the state-of-the-art performance of DPAs.

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