基于时－空过采样系统的点目标检测性能分析

为了提高扫描成像系统对于点目标的探测性能,提出了时-空过采样点目标探测体制,并对其进行了目标检测性能分析。首先,分析了单采样体制在点目标探测中易存在跨像元导致的目标能量分散问题,以及探测器随机高强度噪声及空间质子流尖峰信号导致的虚警问题；然后,提出了用于点目标扫描探测的时-空过采样体制。最后,基于图像信噪比对相同光学系统下单采样和时-空过采样系统的目标检测性能进行了比较分析。分析结果表明,通过过采样方式能够实现目标能量集中到一个像元,保证了图像信噪比需求。通过高分辨率融合使得目标尺度大于噪声及尖峰的尺度,目标尺度最大扩展至3?3像元,基于目标空间相关的处理可以有效降低虚警,提升系统检测性能。

Point target detection based on Temporal-Spatial Over-Sampling system

In order to improve the ability of scanning imaging system detecting the point target, the temporal-spatial over-sampling point target detection system is proposed and then the target detecting performance of the system is analyzed. Firstly, the problem of the target energy dispersion induced by cross-pixels of single sampling system in target detection and the problem of false alarm induced by the random high intensity noise of detector and the spike of space proton flux are analyzed. Then, the Temporal-Spatial over-sampling system used to scan and detect point target is put forward. Finally, the target detecting performance of single sampling and temporal-spatial over-sampling system for the same optical system is comparatively analyzed based on the image signal to noise ratio. The results show that the over-sampling system can guarantee the demand of detecting signal to noise ratio by centralizing the target energy into a pixel. The target scale can be larger than noise and spike scale by high-resolution fusion and the target scale can be extended to 3?3 pixels, then the false alarm of target detection can be decreased effectively based on the scale.