一种基于肖特基二极管低损耗模拟预失真器  

A Low Loss Analog Predistorter Based on Schottky Diode

作　　者：刘武帅 许高明[1,2] 韩栋 刘太君 LIU Wu-shuai;XU Gao-ming;HAN Dong;LIU Tai-jun(Faculty of Electrical Engineering and Computer Science,Ningbo University,Ningbo 315211,China;State Key Laboratory of Millimeter Waves,Southeast University,Nanjing 210096,China)

机构地区：[1]宁波大学信息科学与工程学院,宁波315211 [2]东南大学毫米波国家重点实验室,南京210096

出　　处：《微波学报》2023年第1期72-76,共5页Journal of Microwaves

基　　金：国家自然科学基金(62071264,U1809203);浙江省自然科学基金(LY21F010004);浙江省省属高校基本科研业务费专项资金(SJLY2020013)。

摘　　要：随着通信系统的不断发展,第五代移动通信系统(5G)对射频功率放大器在功耗、延时和带宽等指标都有更高的要求。传统模拟预失真器虽然可以改善功放的非线性,但会引入一定的插入损耗,导致系统的增益下降。为解决损耗问题,文章提出了一种基于肖特基二极管的低损耗模拟预失真器,通过在非线性器件两侧波节点处添加四分之一波长阻抗变换器的方式进行匹配,在改善互调失真量的同时降低插入损耗。实验采用100 MHz带宽,中心频率为3.5 GHz的5G NR信号对中心频率为3.5 GHz的Doherty功率放大器进行线性化。测试结果表明,该模拟预失真器对功放邻信道功率比(Adjacent Channel Power Ratio, ACPR)改善超过14 dB,且插入损耗小于3 dB。With the continuous development of the communication system, the fifth generation mobile communication system(5G) technology has higher requirements for radio frequency power amplifier(RF PA) in terms of power consumption, delay, bandwidth and so on. Although the traditional analog predistorter can improve the nonlinearity of the RF PA, it also has a certain insertion loss, resulting in decrease of the RF PA gain. In order to solve the loss problem, a quarter wavelength impedance converter is added at the wave nodes on both sides of the nonlinear device to match the impedance, which can suppress the intermodulation distortion and reduce the insertion loss. In the experiment, Doherty RF PA operating at 3.5 GHz is linearized by the proposed analog predistorter under a 100 MHz bandwidth 5G NR signal. The test results show that the analog predistorter improves the adjacent channel power ratio of power amplifier by more than 14 dB, and the insertion loss is less than 3 dB.

关 键 词：模拟预失真 5G 阻抗匹配 功率放大器 

分 类 号：TN722.75[电子电信—电路与系统]