A Multi-Pass Median Filter Technique to Remove Ambiguities in Retrieved Wind Fields From Spaceborne Scatterometer Data

An automated median filter-based ambiguity removal algorithm is used because of its simplicity and computational efficiency. The algorithm requires an initial wind field. Consequently the performance of the algorithm depends largely on the accuracy of the initial wind field compared to the true wind field. Usually, an initial wind field consisting of the highest ranked retrieved wind vectors is used. However, we found that this does not result in the best performance. In this paper we present a technique called the multi-pass median filter algorithm. The technique gives superior performance to the conventional median filter algorithm by generating a better initial wind field.