Interpretation of brightness temperature retrieved by supersynthesis radiometer

The supersynthesis radiometer is a kind of synthetic aperture interferometric radiometer. The principle is an interferometric synthesis on the basis of the phase change of the complex correlation (visibility function) between two signals received by two antennas aligned along the vehicle track. The brightness temperature retrieved by the synthesis is the result of the integration of many data measured through different observation angles to the ground. The temperature is numerically evaluated in the case of a flat ground model using the Fresnel reflection coefficients. The off-nadir angle of the interferometer baseline, propagation attenuation of the microwave emission, the angular variation of the emissivity and polarization are taken into consideration for the calculation of the retrieved brightness temperature with three complex dielectric constants of different emissivities