利用改进的LMS算法抑制时变SAR窄带干扰的研究

Time variable narrow band interference suppression for SAR using the algorithm of improved LMS

根据合成孔径雷达(SAR)系统中窄带干扰的特性,提出一种有效的窄带干扰抑制的方法:首先利用Pisarenko谐波分析方法精确地确定干扰的频率,然后对传统的最小均方(LMS)算法进行分段和插值处理,估计出时变窄带干扰的复包络,并通过干扰数据的时域相消和信号幅度的自动增益恢复即可得到干扰抑制后的SAR数据。结合实测数据进行处理,并和传统的自适应频域陷波法和子空间滤波法相比较表明该方法可以更有效地抑制窄带干扰。

Based on the characteristics of narrow band interference（NBI） in synthetic aperture radar （SAR）, a novel approach using the improved Least mean square（LMS） to suppress NBI is proposed. Firstly the frequencies of NBI are obtained by Pisarenko harmonic analysis. Secondly the complex envelopes of NBI are gained through applying the algorithm of LMS segmentally and interpolation. At last the SAR data without NBI are obtained by the subtraction of NBI from SAR data in time domain and amplitude recovery. Compared with the conventional methods of adaptive notch filtering in frequency domain and subspace filtering, the results of measured SAR data show that the proposed approach can suppress the time variable NBI more effectively.