行波管放大器非线性特性对调幅信号边带压缩影响  

Influence of Nonlinear TWTA on AM-Sideband Level Suppression

作　　者：杨蛟龙[1] 屈会鹏[1] 

机构地区：[1]北京跟踪与通信技术研究所,北京100094

出　　处：《飞行器测控学报》2015年第5期475-480,共6页Journal of Spacecraft TT&C Technology

摘　　要：为了更精确地测试星上功率放大器的饱和点,研究分析了TWTA(Travelling-Wave Tube Amplifier,行波管放大器)的非线性特性对AM(Amplitude Modulation,调幅)信号的边带压缩影响。文中基于Saleh模型描述TWTA,分析其在AM信号放大过程中的非线性特性,研究表明:随着输入AM信号的功率不断增大,放大后的输出信号畸变越来越严重;该变化主要体现在AM信号的边带上,与线性工作区相比,在TWTA的饱和点处,经放大后的AM信号的边带压缩程度达到最大。实验结果与理论分析结果完全一致。该研究为通信卫星星上功放饱和点测试提供了一种可行方法。The influence of nonlinear TWTA（Travelling Wave Tube Amplifier）on AM（Amplitude Modulation）-sideband level suppression is studied to measure more accurately the saturation point of satellite TWTA.Saleh model is used to describe TWTA and analyze their nonlinear property of power amplification for AM signals.The study results show that the distortion of the amplified signals will be more serious with the increase of input power and the distortion is mostly on the sideband of AM signals.The most suppression of AM-sideband levels will be achieved at the saturation point of TWTA compared to that in the linear region.Experiment results completely conform to theoretical analysis.A feasible method is proposed for tests of the power saturation point of TWTA for communication satellites based on the study.

关 键 词：行波管放大器(TWTA) 非线性特性 饱和点 调幅信号 边带压缩 在轨测试 Saleh模型 

分 类 号：V556[航空宇航科学与技术—人机与环境工程] TN806[电子电信—信息与通信工程]