A Novel Interference Suppression Method for Interrupted Sampling Repeater Jamming Based on Singular Spectrum Entropy Function

Abstract

As a new type of jamming, the interrupted sampling repeater jamming (ISRJ) derived from the digital radio frequency memory (DRFM) technology, can generate coherent multiple false targets after pulse compression. At present, the traditional interference suppression method and its improved methods have insufficient characteristics and poor detection performance under the condition of low signal-to-noise ratio (SNR). Aiming at addressing this defect, this paper proposes an interference suppression method for ISRJ based on singular spectrum entropy function (SSEF) from the aspects of singular value decomposition (SVD) and information entropy theories. In this method, firstly, considering the local fine characteristics and extraction efficiency, an adaptive multi-scale segmentation (AMS) method is proposed. The purpose of this processing is to extend the salient characteristics while to smooth the similar ones. In AMS, the segmentation criterion based on average energy of segments and the constraint of minimum segmentation is also proposed, then the improved delay embedded matrix is established from the improved trajectory matrix by AMS and delay embedded mapping. Secondly, the singular spectrum of the improved delay embedded matrix is extracted by SVD. Thirdly, because the recognition algorithms based on singular spectrum analysis (SSA), classical SSE and other characteristics fail at low SNR, this paper proposes a characteristic named as SSEF retrieved from the Shannon entropy model. The following proposed entropy-based threshold detection is carried out on the echo signal to realize the band-pass filtering and interference suppression. Finally, experiment results show that in comparison with other interference suppression approaches, SSEF can increase the probability of target detection and the peak-to-side-lobe ratio (PSR) after pulse compression, which validates its stability to noise and jamming especially in the condition of low SNRs.

Intelligent Recognition of Chirp Radar Deceptive Jamming Based on Multi-Pulse Information Fusion

“…Partial-pulse dense transmit jamming (PDTJ) [ 19 ] is generated by a DRFM jammer intercepting part of the radar signal, and then continuously forwarding this pulse to form a large number of dense false targets. Since the formation of PDTJ does not require a DRFM jammer to intercept and store a complete radar signal, it is easy to implement and has strong real-time performance.…”

“…The expression of whole-pulse dense transmit jamming (WDTJ) [ 19 ] generated by the DRFM jammer is found in Equation (14). The jammer copies and stores a complete radar transmission signal, and then forwards it in a certain period.…”

Optimal design of anti‐interrupted sampling repeater jamming waveform for missile‐borne radar based on an improved genetic algorithm

“…In particular, with the development of digital radio frequency memory since the 21st century, interrupted sampling repeater jamming (ISRJ) has been widely used in missile-borne radar confrontation [1][2][3]; this mechanism can form several deception targets along the range direction during the radar tracking process, leading to false target traction or even a failure in tracking. It can also obtain pulse compression gain and realise reduced power to implement effective interference, which has obvious advantages over other interference methods [4,5], and countermeasure approaches based on a single complex waveform become invalid when subjected to ISRJ.…”

An Anti-Jamming Method against Two-Dimensional Deception Jamming by Spatial Location Feature Recognition

“…It can accurately extract non-jamming signals and has better ISRJ suppression performance. In [9], a jamming suppression method based on the entropy function of a singular spectrum is proposed for use with a low signal-to-noise ratio. Through the entropy-based threshold detection of the echo signal, band-pass filtering and jamming suppression are realized.…”