用于Ka波段行波管的反射式可调预失真线性化器  

Design of Reflective Tunable Pre-distortion Linearizer for Ka-Band Traveling Wave Tube Amplifier

作　　者：李文朝[1] 张德伟[2] 周东方[2] 沈晖[1] 李文霞[1] 

机构地区：[1]酒泉卫星发射中心指挥控制站,酒泉735000 [2]解放军信息工程大学信息系统工程学院,郑州450002

出　　处：《真空科学与技术学报》2016年第1期21-27,共7页Chinese Journal of Vacuum Science and Technology

基　　金：国家核高基重大科技专项

摘　　要：为了解决目前模拟预失真器存在的可调性差,增益和相位斜率补偿不够的问题,减小预失真器增益扩展和相位扩张之间的相互影响。本文介绍一种工作于Ka波段的反射式模拟预失真电路,该电路基于90°电桥、肖特基二极管、变容二极管产生预失真信号,利用90°电桥的特性实现电路的匹配,同时通过改变肖特基二极管及变容二极管两端的偏置电压实现对预失真电路的增益扩展和相位扩张特性的控制调节。接着对预失真电路进行非线性分析与仿真验证,在此基础上,将所设计的电路加工为实际的预失真线性化器并与Ka波段的空间行波管联合测试,测试结果表明,线性化后的行波管增益和相位特性从之前的-7 dB和-45°改善到-0.5 dB和-3.5°,三阶交调改善了7.5 dB。A novel type ofreflection-type analog pre-distortion circuit for Ka-band traveling wave tube amplifier（TWTA） was designed to solve the problems of the conventional analog pre-distortion circuit,including but not limited to the poor adjustability,low gain,low phase-slope compensation,and strong impact of the gain on phase expansion of predistortion.The original work included an addition of an analogue electronic-tuned phase shifter,which consists of a 90°bridge,Schottky diodes and variable capacitance diodes（VCD）,and which is capable of generating the pre-distortion signal and matching the gain and phase of TWT,respectively.The novel pre-distortionlinearizer was physically modeled,theoretically analyzed,numerically simulated with ADS software,and experimentally evaluated with a Ka-band TWTA.The measured results show that the new pre-distortion linearizer improves the gain and phase of the TWTA from-7 dB and-45°to-0.5 dB and-3.5°,respectively,and improves the 3 order intermodulation by 7.5 dB.

关 键 词：行波管放大器 预失真电路 增益 位相扩展 三阶交调 

分 类 号：TN830.6[电子电信—信息与通信工程]