Luchinin A. G., Dolin L. S., Kirillin M. Yu.
A method for probing macro inhomogeneities of the water-scattering coefficient by means of a lidar is proposed, the probing beam of which is modulated in power by a high-frequency narrow-band signal, and the receiver detects the variable component of the backscattering signal at the modulation frequency. The possibility of diagnostics of layered scattering structures in water by means of such a lidar has been investigated. An analytical model of the lidar backscattering signal is proposed and limitations of its applicability are formulated. It is shown that the resolving power of a lidar with respect to the spatial inhomogeneities of the water-scattering coefficient can be estimated from the frequency response of the backscatter signal. Examples of calculation of resolution are given and the range of spatial scales of inhomogeneities that can be resulted by a lidar with a modulated probing beam is estimated. The calculation is based on data on the frequency characteristics of the backscatter signal obtained earlier using numerical Monte Carlo simulations. As the obtained estimates show, the proposed method opens up the possibility of diagnosing inhomogeneities structures with scales previously inaccessible to measurements.