分析端接频变负载的多导体传输线FDTD新方法

提出了一种新的有效求解端接频变负载的时域有限差分法（FDTD）.该方法将频域导纳经矢量匹配后以有理式表示，通过逆傅里叶变换将其转换到时域，基于分段线性递归卷积法，推导出该导纳两端的电压和电流关系，将其代入到传输线FDTD模型中，得到了求解端接频变负载多导体（MTL）传输线FDTD的一般公式.对一典型电路进行了仿真，和以状态变量法求解任意负载的结果进行了对比，两者基本重合，说明该方法用来求解频变负载是有效的. 关键词： 多导体传输线 分段线性递归卷积 时域有限差分法 任意负载

A novel FDTD method for multi-conductor transmission lines terminating in frequency-dependent loads

A novel finite difference time domain （FDTD） method has been introduced to analyze multi-conductor transmission lines terminated with frequency-dependent loads. The admittance of frequency-dependent loads can be modeled by rational functions by using vector-fitting, then converting these functions into time-domain by inverse Fourier transform （IFT）. Based on the piecewise linear recursive convolution （PLRC） method, the relation between voltage and current of admittance parameters are deduced. Incorporating the formula into multiconductor transmission lines （MTL） FDTD equations, we get the general formula of MTL FDTD dealing with frequency-dependent loads. In simulating a typical circuit, the results agreed well with the results obtained by using the state-variable transmission model. It shows the method is valid in dealing with frequency-dependent loads.