The effect of feedback on the Volterra series convergence radius

This paper describes the destructive effects of both external and internal feedback on the convergence of the iterative process for finding the Volterra kernels in strongly nonlinear electronic circuits. There is investigated the location of the critical points at which the system loses its analytical properties, and Volterra series begin to diverge. In some cases the critical points for the Volterra series lie in the deep nonlinear region, in other cases these points are directly adjacent to the weakly nonlinear mode. It is found that the failure of the iterative process occurs at the negative and positive feedback, but the latter one limits the convergence radius much more.