A SPICE model of RLGC transmission line with error control

We present a SPICE model for a length of RLGC transmission line. The line is modeled as a characteristic two-port in which the characteristic impedance is approximated as the input impedance of a lumped circuit and the propagation function is approximated as the transfer function of a second lumped circuit plus an ideal delay. We provide a new method to realize a Pade approximation of the characteristic impedance function at any given set of matching frequencies with any given order, and we apply it to approximate the propagation function. The model is stable, exact at s=0 and accurate in the whole frequency region /spl omegaspl isin/(0,/spl infin/). Therefore, for a given accuracy, our model is simpler than the existing models.<
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