K Singhal J Vlach's NILT(Numerical Inversion of Laplace Transform) method is an efficient approach to the transient analysis of lossy transmission lines terminated with linear loads.This technique is utilized in this paper to derive a discrete-time model for transmission lines.The model thus obtained can be easily implemented in general circuit simulators

so that the transient simulation for arbitrary loaded transmission lines can be readily accomplished.Unlike the prevailing frequency domain methods employing the moment-matching technique

no rational approximation is required in this method and numerical problems thus aroused such as stability and preserving of the passivity are avoided.Both uniform and nonuniform lines are dealt with.Numerical experiments carried out by implementing the model into the circuit simulator SPICE have been performed and the results demonstrate the validity and efficiency of the method.