SAR图像分辨率的统计判别准则

Statistical Decision Criterion for SAR Image Resolution

提出了合成孔径雷达(SAR)图像分辨率的统计判别准则。经典的瑞利分辨准则是一个基于人类视觉感知的分辨准则,存在一定的理论缺陷,在SAR图像应用中也存在两个严重问题:没有体现噪声对成像系统分辨能力的影响;没有考虑利用复图像来分辨目标;这些不足限制了SAR图像的应用效能。通过对分辨性能的分析,认为SAR图像的目标分辨问题本质上是一个假设检验问题,进而建立了分辨的假设检验模型,提出了SAR图像分辨率的统计判别准则。分别针对功率图像和复图像的目标分辨,得到了明确的分辨率与信噪比的关系、分辨率与目标相对相位的关系这两个主要结论。这些结果对于SAR系统设计、SAR图像超分辨处理及SAR图像应用都有重要意义。

A novel statistical decision criterion for Synthetic Aperture Radar (SAR) image resolution is presented here. The classic Rayleigh resolution criterion is based on the human visual perception and is defective in theory to some degree. Especially there exist two problems for Rayleigh resolving criterion in the application of SAR image resolution: the influence of noise on resolving ability of imaging system is not demonstrated and the complex image can not be applied by this classic criterion, which is a restriction for the wide application of SAR image. By analyzing the resolving performance of SAR image, the target discrimination is regarded as a hypothesis test problem in this paper. Thus the corresponding hypothesis test model is constructed and a corresponding statistical decision criterion for SAR image resolution is also put forward. As for target discrimination in the power spectrum image and the complex image, two main conclusions are obtained, one is the explicit relation between the resolution and signal-noise-ratio, the other is the explicit relation between the resolution and target relative phase. These conclusions are very significant for the SAR system design, image super resolution and image application.