Polarimetry based on one transmitting and two receiving polarizations: the π/4 mode

The purpose of this study is to assess what can be learnt from polarization duality in reception for a SAR which transmits only one polarization. We focus here on a configuration where the two linear receiving polarizations are oriented at π/4 of each side of the unique transmitted linear polarization. A procedure to estimate a full polarimetric (fp) information over extended targets from this design (hereafter called the π/4 mode) is proposed, when the ity of complex correlation between co- and x-polarized terms is assumed. The behavior of point targets is subsequently considered. The performance assessment (based on SIR-C L band image analysis) relates to the level of information preserved comparatively to fp, but also to the concurrent space segment complexity, in terms of working pulse repetition frequency (PRF), processed swath and down link features.