Comparison of time-varying and non-time-varying Volterra analysis for finding distortion contributions in mixers

The conversion gain in mixers is traditionally calculated using a time-varying (TV) gain model and small signal excitation. In this paper we compare this approach with a brute force expansion of a polynomial model with multitone input. It is seen that the polynomial expansion preserves more information, and shows some distortion products that the time-varying model ignores. The polynomial expansion is used in Volterra-on-Harmonic Balance distortion contribution analysis to analyse both mixing and amplifying circuits.