Analysis of transients in frequency-dependent interconnections and planar circuits with nonlinear loads

A method for the transient analysis of frequency-dependent interconnections and planar circuits terminated with nonlinear loads is presented. The frequency-dependent portion of the system is first analysed to obtain the S-parameters and hence the impulse responses. Two different methods are used to get the scattering parameters: the three-dimensional finite-difference timedomain method and an analytical procedure. The nonlinear convolution equations governing the overall system are then derived and solved numerically. The transient responses of a pair of coupled dispersive microstrip lines, a corner discontinuity, and a microstrip switching circuit are presented.