Investigation of the Atmospheric Turbulence Effects on Electro-Optical Reconnaissance Imaging Systems in the Marine Environment

Abstract

Atmospheric turbulence has a disruptive effect on the optical spectrum of the atmosphere in reconnaissance surveillance systems and especially in military laser operations. The main cause of atmospheric turbulence is that the atmosphere is composed of different gas and aerosol contents and is also subject to meteorological effects. To eliminate the disturbing effects of atmospheric turbulence, it is important to know the turbulence intensity. However, due to the complex structure of the atmosphere, knowing the atmospheric turbulence intensity is a difficult problem to solve. Due to the impossibility of turbulence measurements, especially at long distances, atmospheric turbulence prediction models have been developed. It is preferred to use estimated atmospheric turbulence values for fast information, when navigating over the sea because of this measurement difficulty. This study discusses, the effects of atmospheric turbulence on electro-optical reconnaissance and surveillance systems in the marine environment have been discussed. For this purpose, atmospheric turbulence predictions were made by collecting meteorological parameters in 4 different seasons of 2023 in the Marmara region and using the Sadot-Kopeika prediction model. Atmospheric turbulence measurements were also made at the same location and in the same time periods and compared with the prediction results. To investigate the effects of the atmospheric turbulence on the performance of electro-optical reconnaissance and surveillance systems, DRI (Detection-Recognation-Identification) analyzes of an electro-optical sensor were carried out with the NVIPM (Night Vision Integrated Performance Model) software. The predicted and the measured atmospheric turbulence values have been used in the DRI analyses. When the DRI analysis results were evaluated, it was seen that the performance percentages using the predicted atmospheric turbulence values were compatible with the performance percentages using the measured atmospheric turbulence values. Based on these results, it has been foreseen that by predicting atmospheric turbulence, countermeasures to be taken against turbulence can be developed and electro-optical reconnaissance surveillance systems can also gain the ability to estimate turbulence based on turbulence-induced distortions in the pixels of the cameras.

Keywords

• Electro-optical Systems
• Atmospheric Turbulence
• DRI
• NVIPM

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