Turbulent Lidar: II−Experiment

Abstract

Results of field experiments on horizontal paths using the BSA-2 and BSA-3 turbulent lidars, principles and design of which have been described in the first part, are presented. The BSA-2 lidar operated on 2-km path together with an independent image jitter sensor (IJS); and the BSA-3 lidar, on a horizontal 26-km path. The BSA-2 lidar was used in the experiments aimed at the study of the shape of the backscatter amplification peak, which was found to be 6.5 μrad in our experiments; the sounding was performed with apertures of different sizes. The experimental dependence of the q factor of the effect of turbulence on the size of receiving aperture is derived, which agrees satisfactorily with the Vorob’ev formula. The lidar sounding data and results of the data conversion into the structure parameter of the “optical” turbulence С_n² with the use of the Vorob’ev approximation for homogeneous turbulence are presented. The sounding range was ~10 km. The coefficient of correlation between lidar and IJS data is 0.7–0.8. The sounding in urban environment showed that a horizontal path is not statistically homogeneous; therefore, more complex procedures are to be used for the retrieval of the structure parameter С_n² when solving the inverse problems of lidar sounding of turbulence.