Vol. 39, issue 10, article # 7

Abstract:

Remote sounding of the ocean and atmosphere is currently actively uses aircraft- and space-based lidars. However, sea waves causes fluctuation in backscattering signals, which makes extraction of useful information difficult. Using Monte Carlo algorithms, the work estimates the time-dependent distribution function of the intensity of pulsed laser radiation propagating through the “ocean – air” system with a random (rough) interface at a receiver with a small phase volume. To consider the non-stationarity of a source, local Monte Carlo estimates are applied; a facet model is used to simulate the rough ocean surface. The results of numerical experiments show the effects of system parameters (receiver height, water layer depth, and wind speed which affects the random surface of the ocean – air) on the characteristics of the received signal; these effects are estimated, as well as the influence of the scattering phase function for various spectral ranges. The simulation results can be used to optimize the design of lidars (choice of wavelength and field of view), to develop signal processing algorithms which take into account wave motion, and to predict measurement accuracy depending on hydrometeorological conditions.

Keywords:

Monte Carlo method, laser sounding, sounding of aquatic medium, non-stationary problem

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