论文部分内容阅读
空间环境弱小目标检测是光学成像制导的关键技术之一。当目标与探测器相距较远时,获取的光学图像中目标呈现为无纹理结构特征的弱小点光源。由于各种噪声的干扰,很难把目标与噪声区分开来。介绍了一种基于广义似然比检验的弱小目标检测方法。首先,对空间环境和目标灰度分布特性进行分析,把空间成像目标灰度变化建模为一种强度值围绕固定值发生正弦的变化过程。采用行列均值相减法进行背景抑制,校正探测器响应的非线性,提高图像信噪比。对经过能量累积后图像进行广义似然比判决,从噪声中检测出弱小目标,分析了检测性能,验证模型的合理性。实验证明该算法能够有效检测出空间背景下的弱小目标。
Weak target detection in space environment is one of the key technologies of optical imaging guidance. When the target is far away from the detector, the target in the acquired optical image is presented as a weak point light source without texture features. Due to various noise disturbances, it is difficult to distinguish the target from the noise. A weak target detection method based on generalized likelihood ratio test is introduced. First of all, the spatial environment and the gray distribution characteristics of the target are analyzed, and the change of the gray level of the spatial imaging target is modeled as a sinusoidal change of the intensity value around the fixed value. Using the matrix subtraction method for background suppression, the detector response to the nonlinear correction, improve the image signal to noise ratio. After accumulating the energy, the image is subjected to generalized likelihood ratio judgment, small and weak targets are detected from the noise, the detection performance is analyzed, and the rationality of the model is verified. Experiments show that the algorithm can effectively detect the weak targets in the spatial context.