On the Use of Harmonic Signals to Simulate the Operation of Measuring and Correcting Optical Systems in Turbulent Atmosphere

The paper investigates the correctness of using a harmonic signal to simulate the operation of measuring phase systems, for example, adaptive optics systems that measure and correct turbulent distortions. Estimates of the time evolution of phase distortions have been performed for an optical wave as it propagates in a turbulent atmosphere. When analyzing the evolution of phase distortions in an optical wave caused by turbulence, the ratio of the dispersions of the first and second derivatives is calculated for the increment of phase distortions over a certain time interval. The magnitude of this ratio is compared with the same value in simulation of temporary distortions using a harmonic signal. It turned out that when the time evolution of phase distortions is modeled using harmonic signals, it is necessary to take into account not only the first derivative of this increment, but at least the second derivative as well.