RFI mitigation for SMOS: A distributed approach

The Soil Moisture and Ocean Salinity (SMOS) satellite was launched by ESA on November 2^nd, 2009. Its payload MIRAS, is a two-dimensional L-band interferometric radiometer, and it measures brightness temperatures (BT) in the protected 1400-1427 MHz band. Although this band was preserved for passive measurements numerous radio frequency interferences (RFIs) are clearly visible in SMOS´ data. One method to get rid of these interferences is to create a synthetic signal as close as possible to the measured interference and subtract it from the instrument´s visibilities. Here is described how to create such a signal and how to use it for geo-localization of the sources. Then different methods for assessing the quality of the mitigation are introduced. A possible explanation for the dissimilarity of RFI sources as seen by SMOS is also advanced.