摘要
随着第四代移动通信的高速发展,射频输入信号的包络带宽越来越宽,功率峰均比越来越大,导致采用恒压供电的基站功放效率越来越低。包络线跟踪(ET)技术是大幅提高功放效率的有效方法之一,对于节能减排和缓解环境污染具有重要意义。ET电源是ET技术的核心装置,一般采用开关线性复合(SLH)结构,该结构结合了开关变换器高效率和线性放大器高带宽的优点。本文首先介绍高带宽线性放大器和高效率开关变换器的实现方法,然后介绍SLH ET电源的两个基本架构,即串联和并联架构。在分析这两个基本架构的基础上,提出SLH ET电源的串并联架构的概念,以进一步减小线性放大器输出的功率,提高SLH ET电源的效率。最后,针对现代移动通信对ET电源的要求,从阶梯波提供单元的优化、Ga N器件在ET电源中的应用、包络信号功率频谱的分段方法以及开关变换器控制策略的改进等四个方面提出进一步提升ET电源效率的方法。
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 aconstant dc voltage. Envelope tracking (ET) technique is one of the potential approaches to greatlyimprove the efficiency of the power amplifier in wireless communication system, which contributes toenergy conservation and pollution reduction. ET power supply is the key equipment in ET technique. Itgenerally adopts the switch-linear hybrid (SLH) configuration, which integrates the advantages ofhigh-bandwidth linear amplifier and high-efficiency switched-mode converter. In this paper, thehigh-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-waveprovider, application of GaN devices, split-band for power spectrum of envelope signal, and effective control schemes.
作者
阮新波
金茜
Ruan Xinbo;Jin Qian(Center for More Electric Aircraft Power System Nanjing University of Aeronautics & Astronautics Nanjing 211106 China)
出处
《电工技术学报》
EI
CSCD
北大核心
2017年第4期1-11,共11页
Transactions of China Electrotechnical Society
基金
国家自然科学基金资助项目(51577090)
关键词
移动通信
功率放大器
开关变换器
包络线跟踪
Wireless communication
power amplifier
switched-mode converter
envelope tracking
