Correlation of distributed small satellites SAR echoes

There are both across-track and along-track baseline in Distributed Small Satellites Synthetic Aperture Radar (DSS-SAR), which complicates the correlation of DSS-SAR echoes. After modeling the single-look complex SAR image in DSS-SAR, the new correlation model for DSS-SAR echoes was proposed and derived. According to the relationship between correlation and phase difference of the DSS-SAR image pair, it is proposed that the phase difference of DSS-SAR complex image pair in DSS-SAR includes two parts: one is interferometric phase which is related to terrain elevation, another is azimuth phase which is brought from the along-track baseline and will decrease the terrain height accuracy dramatically. Then a new step, that is applied to remove the azimuth phase, must be added to the interferometric SAR data processing in DSS-SAR and the implementation of the azimuth phase removing step is presented, In the end, computer simulation is given and the results validate the correction of analysis in this paper.