摘要
在电磁兼容测试领域,辐射发射测试是评估电子设备电磁兼容性的关键环节。其中,前置放大器在提升测试系统信号信噪比方面扮演着重要角色。然而,预放的非线性特性可能引入各种失真,进而干扰测试结果的真实性。文章以梳状源辐射测试为研究对象,揭示了预放的两种非线性失真:互调失真和不对称失真。研究表明,被测信号的峰均比过高会导致预放瞬间饱和,产生显著的互调干扰现象,造成高达20 dB的测试误差;同时,预放的不对称性使天线旋转后时域波形失真,接收机频域测试结果出现偏差。深入探讨了前置放大器非线性对测试结果的影响,为辐射发射测试中预放的合理使用提供了理论与实验依据。
In the field of electromagnetic compatibility testing,radiation emission testing is a key step in evaluating the electromagnetic compatibility of electronic devices.Among them,the preamplifier plays an important role in improving the signal-to-noise ratio of the testing system.However,the nonlinear characteristics of pre amplification may introduce various distortions,which can interfere with the authenticity of test results.This article takes comb shaped source radiation testing as the research object,revealing two types of nonlinear distortions in preamplifiers:intermodulation distortion and asymmetric distortion.Research has shown that the peak to average ratio of the measured signal can cause instantaneous saturation of the preamplifier,resulting in significant intermodulation interference and measurement errors caused by up to 20 dB of intermodulation interference;At the same time,the asymmetry of pre amplification causes distortion of the time-domain waveform after antenna rotation,resulting in deviations in the frequency-domain test results of the receiver.This study delves into the impact of nonlinearity in preamplifiers on test results,providing theoretical and experimental evidence for the rational use of preamplifiers in radiation emission testing.
出处
《安全与电磁兼容》
2025年第4期51-55,87,共6页
Safety & EMC
基金
广东省重点领域研发计划项目(2023B0909050007)。
关键词
梳状源
辐射发射
前置放大器
非线性失真
测试精度
comb source
radiation emission
preamplifier
nonlinear distortion
test accuracy
