A new large-signal intermodulation and spurious analysis tool

Nowadays, microwave engineers can use two different tools for nonlinear distortion or spurious analysis: Volterra series and harmonic-balance (and its associated envelope-following alternatives). Unfortunately, although the former provides an analytical model, it is limited to mildly nonlinear regimes, while the latter, being analytic, does not allow any qualitative knowledge of the nonlinear distortion generation mechanisms. The aim of this work is to present an approximate analytical tool, valid in both small and large signal regimes, able to reveal the nonlinear distortion and spurious sources and their possible interactions. For that, the nonlinearities are no longer approximated by Taylor polynomials, as in Volterra series, but in piecewise linear functions for which the Chebyshev transform is known in analytical form.