PD10–Statistical Analysis of Nonlinear Harmonic Distortions in Single Drive Mach Zhender Modulators

In this preliminary investigation, a statistical approach is proposed to analyze the nonlinear harmonic distortions introduced by Mach-Zehnder modulators (MZMs) in response to arbitrarily random radio frequency (RF) excitation signals. The proposed analysis is based on a simple and accurate reformulation of the MZM transfer characteristics using the Taylor series expansion and the Binomial Theorem. Based on this reformulation, a statistical definition for the total harmonic distortion (THD) is introduced. This definition is evaluated for the conventional case of a single tone excitation. Simulation results show a promising agreement between the proposed definition and its deterministic counterpart, which is based on the Fourier analysis technique. Furthermore, Gaussian distributed RF random signals are also considered.