An Advanced Scheme for Deceptive Jammer Localization and Suppression in Elevation Multichannel SAR for Underdetermined Scenarios
Sheng Chang, Shuhe Tang, Yunkai Deng, Heng Zhang, Dacheng Liu, Wei Wang
Abstract
Multichannel synthetic aperture radar (SAR) systems represent a critical advancement in SAR development, yet their effectiveness is increasingly challenged by complex electromagnetic environments. Deceptive jamming, capable of generating false targets, significantly compromises target detection and tracking performance. Conventional blind source separation (BSS) methods fail when jammers exceed system degrees of freedom (DOF), while channel cancellation techniques are ineffective against multiple interference sources. To address these challenges, this paper presents an innovative integrated approach combining jammer localization and suppression. First, jammer directions-of-arrival (DOAs) are estimated via clustering analysis of SAR-imaged data, exploiting the inherent sparsity of deceptive targets to resolve mixing-matrix ambiguity without post-separation identification. Second, a pre-transformation processing method based on sequential quadratic programming (SQP) was implemented to equivalently modify the DOAs distribution of jammers. This innovative approach enables the proposed scheme to effectively handle scenarios with most general distributed jammer directions. Finally, effective jamming suppression is achieved combined with the improved minimum <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"><tex-math notation="LaTeX">$\ell _{1}$</tex-math></inline-formula>-norm method. Experimental results demonstrate significant performance improvements, including a 21.75 dB enhancement in the target region's peak signal-to-noise ratio (PSNR) and an interference suppression ratio (ISR) reduction to -21.75 dB in distributed target, validating the method's effectiveness in general deceptive jamming scenarios.