SMOS simplified iterative full-pol brightness temperature retrieval

Abstract

SMOS is the acronym for the Soil Moisture and Ocean Salinity mission by the European Space Agency (ESA) [1]. Its single payload, the Microwave Imaging Radiometer using Aperture Synthesis (MIRAS), was successfully launched in November 2009. Along more than six years of operation, SMOS calibration and imaging algorithms have undergone a continuous evolution to further improve the accuracy of the retrieved geophysical parameters for a variety of scientific applications related with soil moisture and ocean salinity [2]. This paper analyzes a simplified iterative image reconstruction method that exclusively takes into account the dominant terms in the full-polarimetric equation [3]. This simplified method, that reduces computation time up to 50% at the cost of small radiometric performance degradation, is useful to the L1 teams to fine tune the calibration of the instrument when processing a large amount of data is required.