基于两视处理的单通道SAR地面运动目标检测和定位

A new approach to ground moving target detection and location based on two-look processing for the single channel SAR system

提出一种基于两视处理的单通道合成孔径雷达运动目标检测和定位方法.该方法根据静止场景和运动目标的多普勒谱的偏移不同,先把回波的多普勒谱分成对称两段分别成像,然后对两子视合成孔径雷达图像进行非相干相减,从而对消地杂波,增强数据的信杂噪比,提高运动目标检测能力.在对运动目标进行定位时,从合成孔径雷达图像中加窗取出运动目标的复信号并计算其多普勒谱,通过估计运动目标多普勒谱相对于静止目标的平移量,可对运动目标进行较准确的定位并可进一步降低虚警概率.

A new approach to ground moving target detection based on two-look processing is proposed for the single channel SAR system. In the proposed approach, according to the shifts of the Doppler spectra of moving targets relative to that of a stationary scene, the Doppler spectra of echoes are separated into two parts and focused separately to obtain two sub-lmages; the ground clutter can be suppressed by incoherent subtracting of the two sub-images; so the signal-to-clutter-plus-noise ratio （SCNR） can be improved. The procedures for ground moving targets location are as follows： the detected moving target complex signatures are first extracted by a window in the SAR image after clutter suppression, then the ground moving targets can be precisely located through estimating the Doppler spectra shift quantities between the ground moving targets and clutter through which the constant false alarm rate （CFAR） can be decreased simultaneously. The validity of this method is verified by the simulation data and the measured data.