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Repeater jamming suppression technology based on HHT

Repeater jamming is a newly proposed jamming strategy much effective against linear frequency modulated (LFM) radars. In this paper, a general repeater jamming suppression algorithm is proposed based on Hilbert-Huang transform (HHT). Firstly, with the application of empirical mode decomposition (EMD), the time delay and duration of a repeater jamming can be calculated from the Hilbert-Huang spectrum. Then the repeater jamming is divided into several multi-components LFM segments and the other unknown parameters of each segment are estimated through a modified interpolation on Fourier coefficients (IFC) method. At last, the repeater jamming is suppressed by reconstruction and subtraction in a unified model. Monte-Carlo simulations demonstrate that the variances of the parameters estimation can attain the Cramér-Rao bounds (CRBs) asymptotically, and the proposed algorithm is verified having superior jamming suppression performance.