Multi-view SAR 3D reconstruction method based on essential matrix transformation

Abstract:

SAR can obtain 3D information of the target through multi-view observation. At present, multi-view SAR 3D reconstruction mainly assumes a side-looking trajectory. By constructing projective geometry equations, this type of method calculates the target offset between SAR images and derives the target height from the projective geometry. However, this type of method lacks a mathematical modeling process for the projection relationships and exhibits significant solving errors when the SAR trajectory includes squint and pitch angles. This paper analyzed the linear SAR trajectory, summarized the geometric relationship of the projection, and obtained the mathematical model of multi-view SAR projection. In the mathematical projection model, the relation matrix between pixel coordinates in the SAR imaging plane and target 3D space coordinates is called the essential matrix. The multi-view SAR mathematical model transforms the 3D reconstruction problem into a matrix inverse operation problem. The projection expression established by the essential matrix is transformed into homogeneous linear equations, and the singular value decomposition algorithm is used to solve the 3D coordinates of the target. Spaceborne SAR trajectory parameters were used for experimental simulation to verify the effectiveness of the proposed projection model and 3D reconstruction algorithm.