Low Complexity Interference Mitigation Technique in IRCI-Free SAR Imaging Algorithms

Inter range cell interference (IRCI)-free synthetic aperture radar (SAR) imaging algorithms experience antenna-based interference which severely degrades the SAR image. In this letter, we propose a low complexity interference mitigation technique based on array processing for IRCI-free SAR imaging algorithms. A low complexity array processing is proposed, by designing a linear array with a limited number of fully controllable elements. The complex weight of array elements is optimized for the desired array pattern with constraints on close-in sidelobe levels (SLL). The proposed methodology reduces the desired two-way SLL to 40.5 dB by using only 18 fully controllable elements out of 100 array elements. The state-of-the-art improved-gray wolf optimization (I-GWO) is used for optimization and is shown to be computationally more efficient than some well-known optimization algorithms. Finally, simulated SAR images validate the effectiveness of the proposed technique.