Two- and Three-Dimensional De-aliasing of Doppler Radar Velocities

Abstract Two versions of a two-dimensional approach to Doppler radar velocity de-aliasing were developed and tested on various datasets. One version used fully recursive segmentation of the data and the technique of spatial computer vision to de-alias isolated areas of velocity, whereas the other version utilized spatially constrained segmentation, objective analysis and a nonmeteorological knowledge base for de-aliasing homogenous velocity regions. The utility of the NEXRAD VAD algorithm-derived windfield information was evaluated. A recursive three-dimensional de-aliasing approach was also developed in an attempt to reduce the need for auxiliary windfield information. These approaches were tested on two- (and three) dimensional data in both R, Θ, (Φ) and X, Y, (Z) coordinates and found to produce nearly identical results. Spatial filtering of the data proved to be a nearly preprocessing step and an elective filter was developed which preserves valid velocity information while reducing computational requ...