Modeling the temporal evolution of an aero-optical aberration with the minimum description length principle

A method of building a dynamical model for temporal evolution of an aero-optical aberration is presented. Based on the proper orthogonal decomposition (POD) of the optical aberration, the minimum description length (MDL) principle is used to select a dynamical model for the POD coefficients. The MDL principle can balance the model error against model size so as to prevent the model from overfitting. This strategy is validated with the numerical simulation of the aero-optical aberration caused by the supersonic mixing layer, and the model obtained can accurately predict the time evolution of the POD coefficients in short time. The potential application of our method in extending the bandwidth of the adaptive optics system is also discussed.