不等长非均匀有损耗传输线FDTD瞬态分析

以分析等长均匀无损耗多导体传输线的时域有限差分（FDTD）法为基础,在考虑传输线损耗的情况下,对不等长非均匀多导体传输线进行分析。首先,在考虑传输线损耗的情况下给出传输线上各点电压和电流的迭代计算公式;其次,利用该公式对不等长非均匀有损耗传输线模型进行数值计算和理论分析;最后,通过仿真实验,其结果表明所提计算方法是正确和有效的。该方法对不等长非均匀有损耗传输线的研究提供理论计算参考。     

端接非线性负载的非均匀传输线瞬态分析

在均匀多导体传输线的时域有限差分法(FDTD)基础上，对非均匀多导体传输线及端接非线性负载的情况进行了分析。结果表明：对于非均匀多导体传输线，采用FDTD法进行瞬态分析极为方便，并且可以处理端接非线性负载的情况；同时，还可获得线上各点的电压、电流波过程。通过实例验证了所提出的FDTD算法的有效性，可用于传输线波过程的研究。     

BLT—FDTD 时频结合分析传输线瞬态响应

将频域BLT 方程与FDTD 方法结合起来对包含非均匀线缆的耦合传输线时域响应进行了分析。该方法将非均匀部分线缆从传输网络中独立出来,采用FDTD 离散进行时域分析,然后变换到频域与BLT 方程混合求解整个线缆网络的电压、电流响应。一方面避免了用单一的时域有限差分算法对传输网络进行整体离散时所带来的高计算量、高内存占用比问题;另一方面将非均匀线段当成节点处理,为频域方法求解含非均匀线的传输网络响应,提供了一种新的思路。仿真结果也表明了该方法的有效性。     

有耗耦合传输线瞬态响应的性质与分析

本文从频域电报方程出发,推出了一个描述传输线ABCD矩阵的微分方程,并将其解析解展开为矩阵无穷级数,从数学角度严格地推导出了有耗耦合传输线瞬态响应的两条重要性质。从这些级数还可近似计算ABCD矩阵的值。为了提高效率,采取了将传输线分割成许多相互级联的子网络的步骤。文章最后给出了利用ABCD矩阵分析传输线瞬态响应的方法和两应用实例。与经典的频域模式法相比,该方法完全避免了模式分解的复杂过程,因而其计算机程序更简单,节省了大约一半的内存。     

端接非线性负载的不等长传输线瞬态分析

对时域有限差分(FDTD)法应用于不等长多导体传输线端接非线性负载的情况进行了介绍.首先给出了多导体传输线电报方程和差分公式;然后介绍了不等长传输线的仿真模型;在此基础上,最后通过建立端接非线性负载的不等长多导体传输线模型,对该情况下传输线两端的电压响应进行了分析.数值仿真结果说明了FDTD法解决此类问题的正确性和有效性,为不等长传输线瞬态分析的进一步研究打下了基础.     

不均匀多导体传输线的瞬态分析

针对越来越严重的信号畸变和线间耦合问题,应用时域有限差分法（Finite Difference Time Domain,FDTD）建立了不均匀多导体传输线的仿真模型,并通过MATLAB编程对不均匀多导体传输线两端的电压响应进行了仿真分析.在此基础上,理论说明了各端口瞬态响应的波形特点.结果表明了时域有限差分法用于分析多导体传输系统电磁兼容问题的正确性和有效性,为电磁干扰的预测提供了有价值的参考信息.     

波形迭代法在多导体耦合传输线瞬态分析中的应用

本文提出了在频域应用波形迭代法来分析多导体传输线的瞬态响应。给出的应用实例表明了这个方法的可靠性和某些方面的优势。文章最后还简要地介绍了波形迭代法在传输线分析中的应用前景。     

任意负载有损传输线时域的精细积分法

精细积分法能够有效地对有损传输线时域响应进行分析。通过对精细积分法进行改进，使其不仅能够在时域内很容易地处理具有电抗性质的负载，还可容易地处理如短路、开路这类传统FFT法难以解决的特殊的传输线时域响应问题，极大地提高了精细积分法分析传输线时域响应的功效。     

传输线网络瞬态响应灵敏度分析

在传输线网络瞬态响应灵敏度分析之中,提出了一种基于NILT的新的分析方法。该方法将传输线及其效应连同电子元器件及单元电路作为一个整体,根据传输线在电路中的拓扑关系,将传输线网络瞬态响应灵敏度分析问题转化为求解传输线网络瞬态响应问题,以及传输线ABCD矩阵对电路参数的偏导数问题。通过将ABCD矩阵进行级数展开,极大地简化了ABCD矩阵对电路参数偏导数的计算以及传输线网络瞬态响应灵敏度的分析。本文方法不需要对耦合传输线进行解耦,具有简单、精确、高效等特点,算例结果表明了本文方法的有效性。     

基于精细积分法的耦合传输线瞬态分析

在耦合传输线的瞬态分析中提出了一种基于精细积分法的龙格-库塔迭代法。这是一种时域内的数值解法，该方法在对电报方程进行空间离散而获得对时间的一阶微分方程之后，没有采用精细计算法，而是采用了龙格-库塔迭代法。避免了大量的矩阵运算，提高了传输线瞬态响应分析的效率。     

A Dyadic Green's Function Based Method for the Transient Analysis of Lossy and Dispersive Multiconductor Transmission Lines

This paper describes a new algorithm for the analysis of multiconductor transmission lines characterized by frequency-dependent per-unit-length parameters. The proposed model is based on studying telegrapher's equations as a Sturm-Liouville problem. The open-end impedance matrix is expressed in a series form as an infinite sum of matrices of rational functions, derived from the series form of the dyadic Green's function. The rational form of the open-end impedance matrix allows an easy identification of poles and residues and, thus, the development of a reduced-order system of the interconnect. The pole-residue representation can be synthesized in an equivalent circuit or converted into a state-space model, which can be easily embedded into conventional nonlinear circuit SPICE-like solvers. The numerical results confirm the validity of the proposed modeling technique.     

Passive Macromodeling of Lossy Multiconductor Transmission Lines Based on the Method of Characteristics

This paper presents an efficient passive macromodeling algorithm for distributed lossy multiconductor transmission lines based on the method of characteristics (MoC). A proof is provided that specifies sufficient conditions to guarantee the passivity of the MoC by construction. A key feature of the proposed algorithm is that the curve fitting to realize the MoC depends only on the per-unit-length (p.u.l.) parameters and not on the discretization of the macromodel. Thus, with the knowledge of the rational functions derived by the p.u.l. parameters, the MoC is formulated in a closed form manner for any line length while ensuring passivity.      

任意截面的非平行多导体传输线瞬态分析

以分析多导体传输线的时域有限差分(FDTD)法为基础,在考虑任意截面传输线分布参数无法直接计算的情况下,提出MOM-FDTD 混合方法对不平行多导体传输线进行瞬态分析。首先,利用FDTD建立多导体传输线时域差分模型,然后用MOM 法计算任意截面形状的非平行传输线的分布参数,并且与FDTD法混合进行瞬态分析计算。此算法相对于全波算法,在时间与存储空间消耗上具有很大的优势,并且满足精度要求。最后通过同轴传输线与矩形带状线的例子验证这个方法是正确有效的。     

Analysis of Time Response of Lossy Multiconductor Transmission Line Networks

Systems are considered consisting of an arbitrary number of multiconductor transmission lines joined and terminated by arbitrary linear networks. The fines are assumed to be Iossy, with frequency-dependent parameters. The system is analyzed in the frequency domain, and the inverse Fourier transform is used to obtain the time-domain response.     

Application of Modal Analysis to the Transient Response of Multiconductor Transmission Lines with Branches

An effective method for computing the time-domain response of lossless multiconductor transmission lines with branches in cross-sectionally inhomogeneous dielectric media is presented. Lines of this type are characterized by multiple propagation modes having different velocities. The theory of wave propagation on lossless multiconductor transmission lines with inhomogeneous dielectrics is used to obtain the modal amplitudes on the uniform sections of the line. The scattering matrix for the junction is used to compute the transmitted and reflected waves in the different branches at the junction. Each mode arriving at the junction excites multiple modes in all branches. The method described in this paper identifies all propagation modes in all branches of the line, and leads to the direct physical interpretation of the results. The method is general and can be applied to either partially or completely nondegenerate cases. Experimental results for a six-conductor transmission line with a single branch are found to be in good agreement with the results computed using the described method.     

A Precise Time-Step Integration Method for Transient Analysis of Lossy Nonuniform Transmission Lines

This paper presents a novel time-domain integration method for transient analysis of nonuniform multiconductor transmission lines (MTLs). It can solve the time response of various kinds of transmission lines with arbitrary coupling status. The spatial discretization in this method is the same as the finite-difference time-domain (FDTD) algorithm. However, in order to eliminate the Courant-Friedrich-Levy condition constraint, a precise time-step integration method is utilized in time-domain calculation. It gives an analytical solution in the time domain for the spatial discretized Telegrapher's equations with linear boundary conditions. Large time steps can be adopted in the integration process to achieve accurate results efficiently. In the analysis of transmission lines with frequency-dependent parameters, a passive equivalent model is introduced, which leads to the similar semidiscrete model as that for the frequency-independent case. In addition, a rigorous proof of the passivity of the model is provided. Numerical examples are presented to demonstrate the accuracy and stability of the proposed method.     

Transient Response of Multiconductor Transmission Lines Excited by a Nonuniform Electromagnetic Field

The time-domain transmission-line equations for uniform multiconductor transmission lines in a conductive, homogeneous medium excited by a transient, nonuniform electromagnetic (EM) field, are derived from Maxwell's equations. Depending on how the line voltage is defined, two formulations are possible. One of these formulations is considerably more convenient to apply than the other. The assumptions made in the derivation of the transmission-line equations and the boundary conditions at the terminations are discussed. For numerical calculations, the transmission -line equations are represented by finite-difference techniques, and numerical examples are included.     

任意负载有损传输线时域响应的精细积分法

精细积分法能够有效地对有损传输线时域响应进行分析。通过对精细积分法进行改进 ,使其不仅能够在时域内很容易地处理具有电抗性质的负载 ,还可容易地处理如短路、开路这类传统FFT法难以解决的特殊的传输线时域响应问题 ,极大地提高了精细积分法分析传输线时域响应的功效