Novel Anti-Stealth on Sub-Nyquist Scattering Wave Deception Jammer With Stratospheric Balloon-Borne Bistatic Radar Using KA-STAP-FTRAB Algorithm

Stealth target becomes serious growing threats to the military radar, especially with the recently sub-Nyquist scattering wave deception jammer (SN-SWDJ) which has not countering solution yet, because of the fast sampling rate. This paper engages in improving detection of stealth target (F-117A) under SN-SWDJ effect by using stratospheric balloon-borne bistatic radar system with higher aspect vision. The potential problems of proposed scheme come from heterogeneity caused by sudden gusts of wind, and on the other hand, stealth target is always included in the array data due to the coupling of SN-SWDJ with target motion. To tackle these problems, we introduce an optimal suppression technique with a novel combination of knowledge-aided space-time adaptive processing (KA-STAP) and fast time robust adaptive beamforming (FTRAB) algorithms. FTRAB is applied to remove stealth target components from the array data, as the initial guess of KA-STAP covariance matrix. However, our proposed scheme has a higher complexity of the covariance matrix inversion. To reduce this complexity, we propose the linear affine combination of the inverse covariance matrices' estimation instead of the covariance matrix itself. Simulations demonstrate that the proposed scheme gives much higher location accuracy and reduces complexity comparing with other algorithms.