ISSN 2070-7401 (Print), ISSN 2411-0280 (Online)
Sovremennye problemy distantsionnogo zondirovaniya Zemli iz kosmosa


Sovremennye problemy distantsionnogo zondirovaniya Zemli iz kosmosa, 2017, Vol. 14, No. 3, pp. 78-91

The specifics of SMOS Level 1C data processing for remote sensing tasks

A.S. Yashchenko 1 , P.P. Bobrov 1 
1 Omsk State Pedagogical University, Omsk, Russia
Accepted: 16.05.2017
DOI: 10.21046/2070-7401-2017-14-3-78-91
This paper discusses the general principles of operation of 2-D interferometric MIRAS radiometer (1.4 GHz) mounted on board of the SMOS satellite. The objective of the SMOS mission is remote retrieval of soil moisture and ocean salinity. MIRAS measures brightness temperature at viewing angles from 10° to 65°, its spatial resolution is higher in comparison to counterparts. The soil moisture data are delivered in SMOS Level 2 file. The radiometric data used in remote retrieval of soil moisture are in SMOS Level 1C file. There are difficulties in interpretation of remote sensing data caused by specific features of the MIRAS radiometer. The first is the dependence of the data pixel size on azimuth angle of sensing. The second is the mismatch of two orthogonal polarization planes (H and V) of the radiation received by MIRAS with the radiation polarization planes at the Earth's surface. The paper describes the procedures of measurement at different sensing angles and formation of a radiometric image. The structure of the SMOS Level 1C file and the method of data extraction from the file are considered. This paper also describes the recommendations for data processing of this file. Examples of common errors in the Level 1C file are presented.
Keywords: Microwave radiometry, SMOS ESA mission, soil moisture
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