Comparative Study of Time Domain, Harmonic Balance and Volterra Series Methods for Nonlinear Circuit Simulation

Abstract

onlinear circuit analysis differs from linear circuit analysis in that the transfer characteristic between the input and the output is a function of signal level and the operating point. Different methods were established to manipulate these circuits for different frequency ranges with different excitations. These methods were classified into Time-domain and Frequency domain methods. A brief discussion of each method was mentioned. A simple circuit with a diode which is a nonlinear device was studied for Volterra series and Harmonic Balance methods. Second and third harmonic distortions were calculated for this circuit. Results from Spice and harmonic Balance were arranged for different harmonic amplitudes. The obtained results were compared with the results from SPICE software (Time-domain simulator). A comparative study for the results confirm that for mildly nonlinear circuit the Volterra series is the optimum one, for strong nonlinear circuit a compromise between the accuracy and CPU considerations is the critical parameter for choosing such Harmonic Balance or the SPICE.