基于CEEMD和排列熵的SAR窄带干扰抑制方法

为了有效抑制合成孔径雷达（SAR）系统中常见的窄带干扰（NBI），本文提出一种基于互补集合经验模态分解（CEEMD）和排列熵（PE）的NBI抑制方法。矩峰度系数法用于检测原始回波中是否存在NBI，对包含NBI的回波使用CEEMD将其分解为一系列本征模态函数（IMF）。计算所有IMF排列熵得到全局阈值以区分NBI和有用信号，并使用去除NBI后的IMF分量重建信号以获得良好聚焦的SAR图像。结果表明：所提方法能有效克服经验模态分解（EMD）带来的模态混叠问题，且干扰抑制性能优于传统频域陷波法及基于EMD的NBI抑制方法。

Narrow-Band Interference Suppression Method for SAR Based on CEEMD and Permutation Entropy

In order to effectively suppress the narrow-band interference (NBI) common in synthetic aperture radar (SAR) systems, an NBI suppression method based on complementary ensemble empirical mode decomposition (CEEMD) and permutation entropy (PE) is proposed in this paper. The moment kurtosis coefficient method is used to detect whether there is NBI in the raw echo, and the echo containing NBI is decomposed into a series of intrinsic modal functions (IMF) by using the CEEMD. Calculate the second-order difference of PE of all IMFs to obtain a global threshold to distinguish between NBI and useful signals, and use the IMF components after removing the NBI to reconstruct the signal to obtain a well-focused SAR image. Experimental results show that the proposed method can effectively overcome the mixing problem caused by empirical mode decomposition (EMD), and the interference suppression performance is better than the traditional frequency domain notch filter method and the EMD-based NBI suppression method.