Modeling rainy cells observed in radar echoes

The propagation of electromagnetic waves with very short wavelengths is affected by the presence of various moving targets in suspension in the atmosphere. In particular, for the radars which are intended for the surveillance of the air space, the presence of atmospheric echoes of sufficiently high reflectivity produces a non-negligible interference. This paper deals with the analysis of atmospheric clutter caused by the presence of precipitating clouds. Considering the reflectivity recorded in each pixel, we have calculated and represented the mean variation of the reflectivity factor. We found that the experimental distribution of the reflectivity radar echoes is well modeled as a log-normal distribution or a beta distribution with a coefficient of correlation upper then 0.9.