任意线性集总网络FDTD建模新方法

Novel FDTD method for modeling arbitrary linear lumped networks

提出了一种新的任意线性集总网络的时域有限差分法建模方法,首先将集总网络的频域导纳参数写成多个有理分式之和的形式,通过逆傅里叶变换技术将其变换到时域,然后利用分段递推卷积技术直接将时域导纳参数代入时域有限差分法迭代方程中完成计算.与基于Z变换的建模方法相比,新方法需要较少的变量,同时保留了其显式差分的特点,并具有相同的计算精度.最后,利用该方法对单端口和双端口微带线网络进行建模,计算结果与Z变换建模方法得到的结果吻合.

A novel finite-difference time-domain（FDTD） modeling method for arbitrary linear lumped networks is presented. First, the admittance parameters in the frequency domain of the lumped networks are expressed as a summation of several rational fractions, which are converted into those in the time- domain by means of the inverse Fourier transform（IFT） technique. Then, the piecewise linear recursive convolution（PLRC） method is proposed, the admittance parameters in the time domain are incorporated into the FDTD updated equation directly with the aid of the method. Compared with the modeling methods based on Z-transformation, the proposed algorithm needs fewer variables, preserves the explicit nature, and keeps the same computation accuracy as well. Finally, the method is applied to model some one-, and two-port micro-strip transmission line networks, and simulation results agree well with those obtained by the modeling method available based on Z-transformation.