Radar Volume Backscatter From Spatially Extended Geophysical Targets in a “Slice” Approach

摘要

This paper presents an assessment of the radar backscatter from a spatially extended geophysical target (SEGT) based on a semiempirical (SE) model. An SEGT is any geophysical object that is at least semitransparent to radar illumination (clouds, rain, snowfall in the atmosphere, thick snow cover of the ground). The existing SE model does not take into account the statistical properties of the SEGT''s media. To improve the SE model, a so-called “slice” approach is applied. In this approach, the particles located close to the wavefront of the radar illumination are assumed to produce backscatter that is mainly coherent. This method allows the contribution of the microphysical parameters of the scattering media to the volume component of the radar cross section to be described more comprehensively than the SE model based on the incoherent approach. It is shown that the slice concept results in the original SE model in the particular case when the particle number fluctuation within the slices pertains to the Poisson law.