Experimental measurement of atmospheric coherence length of laser propagation in the atmospheric turbulence

In this paper, According to measurements data from experiment of laser propagation along 0.9Km distance near ground path and 45m ground altitude, the received scintillation fluctuation data and spot size are recorded and analyzed without consider the scale of turbulence. Under the strong turbulence, the structure constant of refractive index Cn2 is computed using scintillation fluctuation and then using models of Cn2 to predict atmospheric coherence length r0 for horizontal paths, later the spot size was computed. Compared with measured data of spot size, there is a certain deviation with 200μm2 from each other under the conditions of r0 < 0.055m, but the time variation is similar, at last, various errors caused by both theory and experiment are analyzed and discussed.