Clutter Suppression for Airborne Weather Radar Using 3D-STAP

摘要

For airborne weather radar, a major task is to detect the echo signal of meteorological targets among severe ground clutter. It is well known that traditional two-dimensional (2D) space-time adaptive processing (STAP) is an advanced technique to detect moving objects under background of ground clutter. However, it is never an easy task to directly apply 2D-STAP method in clutter suppression for airborne weather radar, since as compared to ground moving targets, the motion of some weather targets is relatively slow and the spreading of Doppler is relatively large. To remedy that, we introduce another degree of freedom into traditional 2D-STAP, and thereby propose a so-called three-dimensional (3D) STAP method in this paper. The third dimension of 3D-STAP is the spatial domain in elevation, which can be achieved via multi-channel system in elevation (or vertically displayed array). The related signal processing algorithms of the 3D-STAP are proposed. The performances are analysed and also verified by simulation results. We demonstrate that, the 3D-STAP overperforms the traditional 2D-STAP in case of weather signal detection, and is a feasible way for current airborne weather radar systems equipped with array antenna.