基于子孔径Hough变换的SAR转动目标检测

Sub-Aperture Hough Transform Based SAR Rotational Target Detection

受杂波影响,转动目标SAR回波在距离压缩域呈现断续正弦曲线特征而不易检测。提出一种基于子孔径Hough变换的转动目标检测方法,对全孔径进行分段积累检测,在子孔径内通过FFT将同一距离单元上的信号相干积累以提高信噪比,在孔径间采用广义Hough变换进行非相干积累进一步抑制杂波。该方法适用于硬件开销更小的单通道系统,两级检测获得稳健的杂波抑制性能和更优越的转动目标检测和测量性能。实验仿真结果验证了方法的有效性。

Due to the influence of clutter, the SAR echo of rotational target range-compressed domainpresents a discontinuous sinusoid, which makes it difficult to be detected. A new algorithm based on sub-aperture Hough Transform was proposed to detect rotational target. The detection time duration is dividedinto multiple coherent processing intervals （CPIs） for integration. The echo in same range cell wascoherently integrated via Fast Fourier TransfonrL （FFT） within each CPI to increase SNR, and noncoherentintegration was made among all CPIs via generalized Hough transform for clutter reduction. The proposedapproach is suitable for single-channel SAR system that has a lower hardware cost. The two-stage detectingmethod has better performance on clutter cancellation and rotational target detection. The results of thesimulation indicate the effectiveness of the method.