Mode S anti-reflection algorithm for eliminating false tracks due to reflected replies in ground radar systems

摘要

The invention concerns a method and a system for eliminating false Mode S SSR or 3A code tracks on radar display created by a radar extractor of a radar as a consequence of false replies, i.e. replies reflections against reflectors, a reflector being natural or artificial object different from an aircraft target, the radar comprising the radar extractor and a radar tracker, the method being characterised by the execution of the following steps: A. Creating a raw video map, that is extended to the area covered by the radar and is subdivided into cells of predefinable dimensions, each cell delimiting a portion of the area wherein a aircraft target can be present, to each cell being associated a probability of presence of false replies in such a cell; B. For a situation corresponding to a scan by the radar: B0. Identifying replies clusters, i.e. two or more replies sets closer to each other in azimuth and range than corresponding predefined threshold values; B1. Associating to each cell of the raw video map a power level received by the radar in the corresponding area portion; B2. Extracting the plots, i.e. replies cluster average points determined in case a replies set has a number of replies greater than a predefined threshold, by the radar extractor; B3. Sending the extracted plots to the radar tracker along with said probability of presence of false replies in the cells to which they respectively belong; B4. Calculating, by means of the radar tracker, the tracks relevant to the plots, updating the already existing tracks on the radar display and initiating new tracks using one or more track initiation thresholds chosen on the basis of said probability of presence of false replies calculated in step B3; C. With respect to the all tracks of step B4, determining, by means of the radar tracker, false tracks and relevant initial points; D. On the basis of the initial points of the false tracks determined in step C, calculating the probability of presence of said false replies in the cells corresponding to said initial points and updating the raw video map of step A; E. Repeating steps B-D.