Combination of local and lidar methods in the problem of determining the microphysical propertiesof a scattering medium
We consider the application of a coaxial remote sensing scheme using reflective spheres for backscatter signal calibration. We note the expediency of using a reflecting sphere to model a backscattering lidar signal from the atmosphere. We obtain an expression for the coefficient relating the return signal of the scattering layer to the backscattering coefficient. For microphysical interpretation, the scattering layer is associated with an equivalent layer consisting of monodisperse particles. This layer has the same basic coefficients and angular size transformation of the beam as the layer under study. The microstructure of the equivalent layer (concentration and differential cross section of backscattering on one particle) can be determined from measurements of backscattering signals on particles of the scattering medium. This makes it possible to relate the backscattering and extinction coefficients to the microphysical parameters of the scattering medium.