G. Miano, UNIQUENESS OF SOLUTION FOR LINEAR TRANSMISSION-LINES WITH NONLINEAR TERMINAL RESISTORS, IEEE transactions on circuits and systems. 1, Fundamental theory andapplications, 44(7), 1997, pp. 569-582
Linear transmission lines with nonlinear terminal resistors are consid
ered. Each resistor is assumed to be voltage controlled or current con
trolled and weakly active. These distributed circuits are shown to hav
e a unique solution, which passes at a given instant through a given v
alue, if the characteristics of the terminal resistors satisfy certain
inequalities. In particular, if the resistors are locally passive, th
en the solution is unique. Transmission lines with terminal resistors
that are locally active may admit several solutions that have the same
initial value. In these cases, the uniqueness of solution is obtained
adding ''small'' capacitances in parallel to the voltage controlled r
esistors and ''small'' inductances in series to the current controlled
resistors.