针对旋翼微动目标杂波抑制问题，研究了一种基于复数据经验模态分解（CEMD）的微动目标杂波抑制方法。首先，建立了地杂波背景下的旋翼微动目标信号模。然后，根据杂波和微动信号在时频域的差异性，基于CEMD和Gabor变换，通过新定义的不同本征模态函数（IMF）的能量所占总能量的比重，选择出微动信号占优所对应的几个IMF分量，并基于这些IMF对旋翼微动目标进行时域和时频域重构，实现旋翼微动目标和杂波的分离，达到抑制杂波提取微动目标回波的目的。最后，与常规杂波抑制方法进行了对比，仿真结果验证了所提方法的有效性。
A method for clutter suppression of the micro-motion target is proposed based on Complex Empirical Mode Decomposition (CEMD). First, a model for the rotor micro-motion target signal mixed with the ground clutter is established. Second, the differences of the clutter and the micro-motion signal in the time-frequency domain are analyzed. Based on Gabor transform and CEMD, several Different Intrinsic Mode Functions (IMF) components when the micro-motion signal is superior are selected according to the proportion of the energy occupied by IMF in the total energy. The rotor micro-motion target in the time domain and time-frequency domain is then reconstructed to separate the clutter from the rotor micro-motion target and achieve the effect of clutter suppression. Finally, the method proposed is compared with the conventional method. Simulation results verify the effectiveness of the proposed method.
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