Experimental Research On The Turbulent Atmosphere Influence To Active IR Laser Detection

In this paper, the model of atmosphere turbulence, refractive-index fluctuation power spectrum, a simplified model applicable for all fluctuation section of turbulence and the effects of the turbulent atmosphere on the laser beam propagation in the atmosphere are researched systematically. The technology basis on far IR laser active detection, include constitution, operating principle, "cat-eye effect", the echoing characteristic of thermal-imaging system in active detection and ranging equation, is introduced. According to extended Huygens-Fresnel principle, it analyzes intensity fluctuation of detector's receiving plane which is in atmosphere turbulence. Finally, the experiment of how atmospheric turbulence affect active detection is introduced detail. The experiment on desert in Northwest China indicates that the intensity of turbulent atmosphere is weakly at sunrise or sunset, its effect on the echo ratio of active detection is also the minimum and is strongly at midday, its effect on the echo ratio of active detection is also relatively stronger. Through comparing the experiment result with the change of turbulent atmosphere data in White Sands experiment base in one day, we estimate : above-mentioned phenomena is a generally in desert area.