Abstract：With the rapid development of the fourth generation (4G) wireless communication system, the envelope of radio frequency signal is featured with continuously increasing bandwidth and peak-to-average power ratio. It would worsen the efficiency of the power amplifier supplied by a constant dc voltage. Envelope tracking (ET) technique is one of the potential approaches to greatly improve the efficiency of the power amplifier in wireless communication system, which contributes to energy conservation and pollution reduction. ET power supply is the key equipment in ET technique. It generally adopts the switch-linear hybrid (SLH) configuration, which integrates the advantages of high-bandwidth linear amplifier and high-efficiency switched-mode converter. In this paper, the high-bandwidth linear amplifier and high-efficiency switched-mode converter are introduced firstly. Then, series- and parallel-connections of SLH ET power supply are presented. After that, the series-parallel form SLH ET power supply is proposed to further reduce the power loss in the linear amplifier and to achieve a higher overall efficiency. Finally, the solutions are proposed to further increase the overall efficiency of SLH ET power supply, according to the optimization of step-wave provider, application of GaN devices, split-band for power spectrum of envelope signal, and effective control schemes.
阮新波, 金茜. 包络线跟踪电源技术综述[J]. 电工技术学报, 2017, 32(4): 1-11.
Ruan Xinbo, Jin Qian. A Review of Envelope Tracking Power Supply. Transactions of China Electrotechnical Society, 2017, 32(4): 1-11.
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2017, Vol. 32 
