用于Ka波段接收机末级的预失真线性化器  

Design of pre-distortion linearizer for Ka-band final amplifier of receiver

作　　者：何戎根 陈建荣 方龑 HE Rong-gen;CHEN Jian-rong;FANG Yan(Institute of Space Radio Technology,Xi＇an 710100,China)

机构地区：[1]空间电子信息技术研究院,陕西西安710100

出　　处：《电子设计工程》2018年第18期145-149,154,共6页Electronic Design Engineering

摘　　要：为满足接收机线性度要求,末级中功率放大多采取高功率回退的做法,这无疑是对接收机功率的浪费,采用线性化器与放大器级联方式能减少功率回退量。本文介绍一种改善中功率放大器弱非线性的模拟预失真电路,该电路由非线性支路与线性支路两路合成,基于肖特基二极管产生非线性,利用90°分支线耦合器特性实现电路的匹配,同时通过改变肖特基二极管电压及线性支路的衰减与相移实现对预失真电路的三阶互调值幅度与相位的调节。对预失真电路进行非线性分析与仿真验证,并与中功率放大器级联仿真。ADS双音测测试结果表明,线性化后中功率功放在回退13 dB工作点处的三阶互调值由51.8 dBc改善到72.8 dBc补偿21 dB,五阶互调值也保持在70 dBc以下。In this paper,ananolog pre-distortion linearizer was designed to improve linearity of the receiver,which final amplifier working in high power back-off condition.This linearizer circuit is composed of nonlinear branch,used anti-parallel Schottky diodes,and linear branch.By changing the attenuation and phase shift of the linear branch and schottky diode voltage,the three-order intermodulation（IMD3）amplitude and phase can be controlled.By applying this linearizer to ADS soft,two tones test results show that The IMD3 at the power-back in 13 dB was improved from 51.8 dBc to72.8 dBc,and the IMD5 remained below 70 dBc

关 键 词：预失真 弱非线性 接收机功耗 三阶互调对消 

分 类 号：TN721[电子电信—电路与系统]