2-D Frequency Domain Imaging of Bistatic SAR Based on Legendre Polynomial Expansion

For bistatic SAR in slanting flight mode of any configuration, a 2-D frequency domain imaging algorithm for bistatic SAR based on Legendre orthogonal polynomial approximation is proposed. Based on the Legendre polynomial expansion of the slant range function, the 2-D spectrum of the point target is derived, which eliminates the coupling of range and azimuth of the echo signal and makes the imaging processing more efficient. Point target of scene region is imaged by 2-D frequency domain imaging algorithm in 2-D frequency domain. The algorithm improves the focusing effect of scene edge points and increases the focusing depth of scene edge points. The theoretical derivation and simulation results verify the effectiveness and feasibility of the proposed algorithm.