Equivalent Circuits for Nonuniform Transmission Line Simulation

摘要

The hereby article is devoted to elaboration of the analysis method of nonuniform transmission line (NUTL) with utilization of typical circuit simulator like SPICE. It is assumed that quasi-TEM modes are propagated in the NUTL. Solution of the problem is divided into three parts. 1) The analysis of nonuniform transmission line is reduced to the analysis of cascaded sections of linear varied nonuniform transmission line (LNTL). Proper algorithm originates from literature. 2) Computational model of linear varied nonuniform transmission line is elaborated following the asymptotic waveform evaluation methodology. The q-pole model is matched to imitate position of zeros and poles of admittance matrix of the NUTL. 3) Synthesis of passive circuit which implements the model for broad range values of LNTL slope constant. Consequently parameters of the circuit can be evaluated precisely as polynomial function of slope constant. Resultant model can be easily written in SPICE simulation language.