Processing of Bistatic SAR Data With Nonlinear Trajectory Using a Controlled-SVD Algorithm

• Published in: IEEE journal of selected topics in applied earth observations and remote sensing Vol. 14; pp. 5750 - 5759
• Main Authors: Xiong, Yi, Liang, Buge, Yu, Hanwen, Chen, Jianlai, Jin, Yanghao, Xing, Mengdao
• Format: Journal Article
• Language: English
• Published: Piscataway IEEE 2021; The Institute of Electrical and Electronics Engineers, Inc. (IEEE)
• Subjects: Algorithms; Azimuth; Bastatic; Echoes; Image quality; Imaging techniques; Interpolation; nonlinear trajectory; Radar imaging; SAR (radar); Scaling; Signal processing algorithms; Singular value decomposition; singular value decomposition (SVD); Synthetic aperture radar; synthetic aperture radar (SAR); Trajectory; Trajectory control; Transmitters
• ISSN: 1939-1404; 2151-1535; 2151-1535
• DOI: 10.1109/JSTARS.2021.3084619

The nonlinear trajectory and bistatic characteristics of general bistatic synthetic aperture radar (SAR) can cause severe two-dimensional space-variance in the echo signal, and therefore it is difficult to focus the echo signal directly using the traditional frequency-domain imaging algorithm based on the assumption of azimuth translational invariance. At present, the state-of-the-art nonlinear trajectory imaging algorithm is based on singular value decomposition (SVD), which has the problem that SVD may be not controlled, and thus may lead to a high imaging complexity or low imaging accuracy. Therefore, this article proposes a nonlinear trajectory SAR imaging algorithm based on controlled SVD (CSVD). First, the chirp scaling algorithm is used to correct the range space-variance, and then SVD is used to decompose the remaining azimuth space-variant phase, and the first two feature components after SVD are integrated to make them be represented by a new feature component. Finally, the new feature component is used for interpolation to correct the azimuth space-variance. The simulation results show that the proposed CSVD can further improve the image quality compared with SVD-Stolt.