一种基于二极管的L波段行波管预失真电路

A Diode-Based Predistortion Circuit of L-Band Traveling Wave Tube

该文分析了行波管放大器的输入输出曲线,并计算得到理想预失真线性化电路的增益和相位响应曲线。提出一种由两条非线性支路组成的预失真电路,并讨论了电路中肖特基二极管主要参数对预失真曲线的影响。设计制作了L波段预失真电路,并与行波管放大器联合测试,实验结果表明,加入预失真电路后,行波管放大器三阶交调载波比IM3在输入功率回退3 d B、6 d B、9 d B时分别从-10.3 d Bc、-14.3 d Bc、-18 d Bc改善到-12.1 d Bc、-18.5 d Bc、-26.9 d Bc。

Based on the polynomial model of TWTA（ Traveling Wave Tube Amplifier） and ideal predistortion response curve,a novel diode-based predistortion Linearizer which consists of two non-linear branches was developed. The influence of the diode parameters to predistortion response curve was discussed. Based on the analysis and simulation,a L-band practically predistortion cuicuit was designed and tested with the TWTA. The IM3 of TWTA with linearizer at Input Power Back Off（ IPBO） of 3d B,6d B,9d B can separately be improved from-10. 3 d Bc,-14. 3 d Bc,-18 d Bc to-12. 1 d Bc,-18. 5 d Bc,-26. 9 d Bc.