摘要
为了提高毫米波功率放大器的回退效率并拓展工作带宽,文中对毫米波频段氮化镓包络跟踪(Envelope Tracking,ET)功率放大器进行了实验研究。采用0.15μm氮化镓工艺的功放芯片,由线性电源调制器馈电,进一步采用数字预失真技术改善输出波形的非线性失真来提高线性电源调制器的工作带宽,最终在提高功放芯片效率的同时提升了其线性度。实验测试结果表明,在23~28 GHz频率范围内,当分别采用40MHz带宽峰均比为8.6 dB和80 MHz带宽峰均比为6.4 dB的正交频分复用(OFDM)64QAM调制信号进行测试时,恒压供电的功率放大器的回退效率分别为7.5%~10.1%和12.3%~16.5%,而采用线性电源调制器供电的ET功放回退效率为9.6%~14.3%和16.3%~22.1%,平均提升3%~6%左右,经过数字预失真处理后的邻近信道功率泄漏比均低于-30.1 dBc。
In order to improve the power back-off(PBO)efficiency and bandwidth of millimeter wave power amplifier(mm-wave PA),a mm-wave GaN envelope tracking(ET)power amplifier is experimentally studied in this paper.The 0.15μm GaN process power amplifier chip is supplied with the linear power supply modulator and the digital pre-distortion(DPD)technology is further used to improve the nonlinear distortion of the output waveform for improving the working bandwidth of the linear power supply modulator.Finally,the linearity of the power amplifier chip is improved while ensuring the high efficiency of the power amplifier chip.The tested results show that when driven by a 40 MHz OFDM with a peak to average ratio of 8.6 dB and an 80 MHz with a peak to average ratio of 6.4 dB signals respectively,the PBO efficiency of mm-wave PA with constant voltage power supply and linear supply modulator power supply are 7.5%-10.1%,12.3%-16.5%and 9.6%-14.3%,16.3%-22.1%.The PBO efficiency is increased by 3%-6%.After using DPD technology,the adjacent channel power leakage ratio of mm-wave PA is less than-30.1 dBc。
作者
赵子明
朱晓维
ZHAO Zi-ming;ZHU Xiao-wei(State Laboratory of Millimeter Waves,Southeast University,Nanjing 210096,China)
出处
《微波学报》
CSCD
北大核心
2023年第2期11-15,共5页
Journal of Microwaves
基金
科技部国家重点研发计划(2020YFB1804905)。
关键词
回退效率
毫米波功率放大器
线性调制器
数字预失真
back-off efficiency
mm-wave power amplifier(PA)
linear supply modulator
digital pre-distortion(DPD)
作者简介
赵子明,男,1991年生,博士生。主要研究方向:射频功率放大器,包络跟踪技术;通信作者:朱晓维,男,1963年生,教授,博士生导师。主要研究方向:功放及其预失真技术,电路与系统。E-mail:xwzhu@seu.edu.cn。
