一种用于毫米波行波管的微带预失真电路  

Micro-strip Predistortion Circuit for Millimeter-wave Travelling Wave Tube

作　　者：虞崇志 胡波雄[1] 唐康凇[1] 王刚[1] 苏小保[1] YU Chongzhi HU Boxiong TANG Kangsong WANG Gang SU Xiaobao(Institute of Electronics, Chinese Academy of Sciences, Beijing 100190, China University of Chinese Academy of Sciences, Beijing 100049, China)

机构地区：[1]中国科学院电子学研究所,北京100190 [2]中国科学院大学,北京100049

出　　处：《电子与信息学报》2017年第2期474-481,共8页Journal of Electronics & Information Technology

基　　金：国家科技重大专项(2012ZX01007004001);国家自然科学基金(61401427)~~

摘　　要：随着通信技术的发展,行波管预失真电路的研究变得越来越重要。该文针对基于肖特基二极管的非线性发生器,首次分析了二极管SPICE(Simulation Program with Integrated Circuit Emphasis)模型参数中零偏压结电容和串联电阻对预失真扩张曲线的影响。对目前的微带预失真电路工作在K波段以下,绝对或相对带宽一般不超过1.8 GHz和4%,需在输入及输出端加隔离器等不足,基于ADS(Advanced Design System)软件设计并加工了一种用于中心频率30 GHz,绝对和相对带宽为2 GHz和6.67%的毫米波行波管的微带预失真电路。分别测试行波管和级联线性化器后的行波管,29 GHz,30 GHz和31 GHz的增益和相位压缩量分别可以从7.5 d B和40?,7.3 d B和50?,7.1 d B和59?改善到3.8 d B和10?,3.7 d B和12?,2.4 d B和15?以内。双音测试结果表明,为了达到通信中载波与三阶交叉调制分量抑制比(C/IM3)25 d Bc的要求,单独行波管在29 GHz,30 GHz和31 GHz时需分别回退17 d B,18 d B和18 d B,而加入线性化器后的行波管,只需分别回退12 d B,9 d B和8 d B,也即加线性化器可改善5 d B,9 d B和10 d B,极大地提升了行波管的线性度,具有重要工程应用价值。With the development of communication technology, investigating predistortion circuit for Travelling Wave Tube （TWT） becomes more and more important. This paper analyzes the principle of nonlinearity generator based on the schottky diodes and the effects of the zero bias junction capacitor and series resistor of the diode Simulation Program with Integrated Circuit Emphasis （SPICE） model on the expansions of the circuit for the first time. The conventional micro-strip predistortion circuits, whose absolute or relative bandwidth are less than 1.8 GHz and 4%, work at below K band, and need isolators to match the input and output ports. Based on the Advanced Design System （ADS） software, it is designed that a micro-strip predistortion circuit for millimeter wave band TWT at center frequency 30 GHz, absolute bandwidth 2 GHz, and relative bandwidth 6.67%. The results of experiments show that the compressions variations of gain and phase are from 7.5 dB and 40°, 7.3 dB and 50°, 7.1 dB and 59° to less than 3.8 dB and 10° , 3.7 dB and 12°, 2.4 dB and 15° for the TWT without and with the linearizer at 29 GHz, 30 GHz and 31 GHz respectively. The two tones test results show that the Input Power Back Off （IPBO） are 17 dB, 18 dB and 18 dB for the TWT, but 12 dB, 9 dB, and 8 dB for the Linearized TWT （LTWT）, namely 5 dB, 9 dB, and 10 dB improvements with the linearizer at 29 GHz, 30 GHz, and 31 GHz respectively for the demand of 25 dBc Carrier to third InterModulation （C/IM3） ratioin in communication system. The linearity of TWT is clearly improved with the linearizer, which serves as a great value for engineering application.

关 键 词：行波管 肖特基二极管 预失真器 增益和相位扩张 载波与三阶交叉调制分量比 

分 类 号：TN124[电子电信—物理电子学] TN830.6