基于反射测量的噪声源阻抗提取方法

A Noise Source Impedance Extraction Method Using Reflection Measurement

提出了一种提取受试设备(EUT)电源端口的噪声源阻抗的方法。该方法采用反射测量法测量EUT端口与人工电源网络(AMN)端口的S参数,并通过EUT的噪声源阻抗模型推导出共模阻抗与差模阻抗。分别采用纯电阻π型网络与无源滤波器作为模拟EUT负载进行实验,结果表明所提方法在9 kHz~30 MHz频段内提取1 kΩ内的共模、差模噪声源阻抗数据与采用传统S参数法的测量数据相吻合,实现了对EUT噪声源阻抗的简便测量。

A noise source impedance extraction method for power supply ports of the equipment under test(EUT)is provided.In this method,the reflection measurement method is taken to measure the S parameters of the EUT and the artificial mains network(AMN)ports.Based on the EUT noise source impedance model,the common mode impedance and the differential mode impedance are further derived from the measurement results.A series of pure resistanceπnetworks and a passive filter have been respectively taken as simulating EUT load in verification experiments.The results show that the common mode and the differential mode impedance ranged from 1Ωto 1 kΩextracted by this method coincide with the results measured from conventional S parameter method in 9 kHz~30 MHz frequency range.This method realizes a convenient extraction for EUT noise source impedance.