An effective method for generating initial condition in harmonic balance analysis using method of nonlinear currents

This paper presents a solution to one of the most troublesome sections of Newton algorithm for solving harmonic balance nonlinear system of equations which is choosing an appropriate initial condition. A good initial condition guaranties the convergence of the algorithm. Here, we have used Volterra series analysis to calculate the appropriate initial condition for the harmonic balance analysis. To demonstrate the performance of the Volterra assisted harmonic balance (VAHB) method we have compared the response of a typical nonlinear circuit with two other techniques. These techniques are implemented in the commercial ADS software. They exploit arbitrary initial condition and initial condition based on the transient analysis of the nonlinear circuit. Based on the calculated results the VAHB technique has a superior performance in terms of convergence with respect to other techniques.