This paper presents an iterative perturbation technique for the time-domain analysis of nonuniform transmission lines. Compared with the mostly reported frequency-domain methods, the time-domain method possesses the advantages of efficient computation and intuitive observation of computed results. For the consideration of nonuniformity, the place-dependent variation of the per-unit-length parameters is interpreted as perturbations relative to uniform transmission lines. The nonuniform transmission lines can thus be regarded as the superposition of the unperturbed part and the perturbed part. Starting from the Telegraph's equation, the time-domain expression of the proposed method is derived. Then, multisteps consecutive perturbations based on the finite-difference time-domain method are formulated to analyze the field-line coupling problem. As the perturbation order increases, the perturbation value converges rapidly to a certain value. The technique is validated through the analysis of an overhead multi-conductor nonuniform transmission lines. The high efficiency of the proposed method in solving the electromagnetic compatibility problem with randomicity is verified and applied by analyzing a nonuniform transmission line with randomly varying paths.

中文翻译：

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用时域扰动技术分析非均匀传输线

本文提出了一种用于非均匀传输线时域分析的迭代扰动技术。与大多数报道的频域方法相比，时域方法具有计算效率高和计算结果直观观察的优点。考虑到非均匀性，每单位长度参数的位置相关变化被解释为相对于均匀传输线的扰动。因此，非均匀传输线可以看作是未扰动部分和扰动部分的叠加。从电报方程出发，推导出所提出方法的时域表达式。然后，提出了基于有限差分时域方法的多步连续扰动来分析场线耦合问题。随着扰动阶数的增加，扰动值迅速收敛到某个值。该技术通过对架空多导体非均匀传输线的分析得到验证。通过分析具有随机变化路径的非均匀传输线，验证并应用了所提出的方法在解决具有随机性的电磁兼容性问题方面的高效率。