Propagation of ultra-wideband radio pulses in cold plasmas

The laws of space-and-time evolution of ultra-wideband (UWB) and ultrashort (US) signals (pulses) in dispersive media of various physical nature, were studied. It was observed that the energy transmitted by these pulses is concentrated within a small spatial interval of several dozen centimeters and even several centimeters. It was found to restricts the applicability of traditional methods based on the Fourier expansion to describe the dispersion-induced distortions of UWB pulses. The analytical description of the UWB and US pulse propagation in cold collisional plasmas as applied to ionosphere was also discussed. The family of RM-KNN filters for the image processing uses the combined RM estimates with a goal to enhance the robust properties of a standard KNN filter. The modification of the RM estimates for processing 3D images is proposed and 3D RM-KNN filters are defined as 3D Mm-Knn ones.