一种估算微带传输线辐射敏感性的解析电路模型

Analytic circuit model for radiated susceptibility estimation of the microstrip transmission line

根据传输线理论和电磁场理论,文中提出了一种估算微带传输线辐射敏感性的时域解析电路模型.该模型能够快速得到微带传输线对外界电磁干扰的敏感阈值,使用国际电工委员会横电磁标准62132-2规定的横电磁小室作为测试环境,选用具有陡峭边沿能直观地呈现微带传输线辐射敏感性的传输线脉冲作为电磁干扰信号.以此模型应用实例来说明模型的有效性,得到了具体的解析电路模型参数,由模型计算和测试结果的对比验证了该模型的准确性.此外,运用该模型进一步计算了不同负载时微带传输线对传输线脉冲的响应情况,并计算了响应中电场耦合和磁场耦合的贡献,得到了负载变化对微带传输线辐射敏感性的影响规律,从而可由负载的选择来提高微带传输线的辐射敏感性.

According to transmission line theory and electromagnetic theory, a time-domain analytic circuit model for radiated susceptibility estimation of a microstrip transmission line is proposed. In order to obtain the susceptibility threshold of a microstrip line under external electromagnetic interference quickly, a transverse electromagnetic cell （due to IEC standard 62132-2） is adopted as the test environment. A transmission line pulse is chosen as the external electromagnetic interference, since its steep edges can directly demonstrate radiated susceptibility of a microstrip line. This is an application case to identify the availability of the model. Specific parameters of the analytic circuit model are derived and comparisons of calculated and measured results of transmission line pulse responses for the matched microstrip line confirm the accuracy of the model. Furthermore, transmission line pulse responses of a microstrip transmission line with arbitrary loads and contributions of electric and magnetic field couplings are calculated. The effect of terminal load on the response of a microstrip transmission line is obtained, which can be helpful for load- selection to improve radiated susceptibility estimation of a microstri~ transmission line.