矢量网络分析仪阻抗特性测量误差分析与验证

Analysis and Verification of Measurement Error of Impedance Characteristic of Vector Network Analyzer

为了考察50Ω特性阻抗的矢量网络分析仪对非50阻抗被测网络的测量误差,提出了基于不同特性阻抗空气线的实验验证方法,加工制作了12根不同特性阻抗的2.4 mm同轴连接器空气线。通过理论计算和实验分析可得到以下结论:随着被测网络阻抗偏离50Ω,测量误差有增大趋势,在50Ω特性阻抗附近误差相对较小;不同特性阻抗被测网络的测量误差随频率增大而增加;测量误差对终端端接负载特性比较敏感,端接50Ω负载时测量误差较小,而端接开路器与短路器时测量误差较大。通过对不同特性阻抗的空气线测量分析,发现在5～100Ω之间有较低的测量误差,可以满足一般工程测量要求。

In order to investigate the measurement error of the vector network analyzer with 50 Ω characteristic impedance to the non-50 Ω impedance measured network, an experimental verification method based on air lines with different characteristic impedances is proposed, and twelve air lines of 2. 4 mm coaxial connectors with different characteristic impedances are processed and produced. Through theoretical calculation and experimental analysis, these conclusions can be obtained that with the measured network impedance deviates from the 50 Ω, the measurement error increases, and the error is relatively small near the 50 Ω characteristic impedance, and the measurement error of the measured network with different characteristic impedance increases with the increase of frequency, and the measurement error is sensitive to the terminal end load characteristics, it is smaller when the 50 Ω load is connected, but it is larger when the open and short circuit is connected. Through the measurement and analysis of air lines with different characteristic impedance, it is found that there is a low measurement error between 5 ~100 Ω, which can meet the general engineering measurement requirements.