针对点目标探测的背景杂波量化改进方法

干扰。传统分块方差统计法会引入背景低频波动，使杂波偏大，而且杂波度量值随分块单元尺度变化
较大。本文提出一种基于匹配滤波的杂波量化改进方法，首先以点目标像斑分布为模板，对背景图像
进行匹配滤波，得到互相关矩阵；然后将高相关性区域标记为杂波重点区域，计算方差作为局部杂波，
取局部杂波的均方根作为全局背景杂波。该方法突出了对空间杂波区域的选择性，能有效降低背景低
第 40 卷 第 4 期 2018 年 4 月
红外技术 Infrared Technology
Vol.40 No.4 Apr. 2018
〈图像处理与仿真〉
针对点目标探测的背景杂波量化改进方法
童锡良，周 峰
（北京空间机电研究所，北京 100094）
摘要：在点目标探测模型中，目标的形状纹理信息丢失，可用特征少，背景杂波对目标检测造成严重
Improved Clutter Quantification Method for Point Target Detection
TONG Xiliang，ZHOU Feng
(Beijing Institute of Space Mechanics & Electricity, Beijing 100094, China)
收稿日期：2017-06-01；修订日期：2018-04-04. 作者简介：童锡良（1989-），男，博士生，研究方向是红外点目标探测，遥感载荷总体设计。E-mail：xltong1230@。
Abstract：In the point target detection model, the shape and texture information of the target is almost lost, and the number of characteristics available for the detection is small, so clutter caused by background may lead to serious interference in post-processing. The traditional block variance statistic method takes low-frequency fluctuation into account, which makes the clutter larger than its real value, and the clutter quantification result varies greatly with unit scale. In this paper, an improved clutter quantification method based on matched filtering is proposed. First, the background image is filtered with a matched mask obtained by a target speckle, and the result is the cross correlation matrix of the background to the target. Then, regions with high correlation are selected to calculate the variance as a local clutter. At last, the root mean square of the variances are taken as a global background clutter. The improved method filters the background to select a reasonable clutter region. It can effectively reduce low-frequency fluctuation of the background, and the result is stable to block the scale. Clutter quantification and the point target detection simulation are conducted. The results show that the method proposed in this paper is robust to unit scale. Compared to the traditional method, it has higher correlation between the clutter and the probability of detection. Key words：clutter assessment，point target detection，speckle distribution，matching filter，probability of detection
0 引言
杂波是指目标探测场景中，与目标信号相似，会 对目标检测产生干扰的背景信号。随着遥感系统光 学、探测器及制冷技术的发展，光学像差和探测器噪 声对目标探测的影响越来越小，杂波逐渐成为限制光
电成像探测系统性能的关键因素[1-2]。在远距离弱点目 标探测模型中，目标能量集中在少数几个像元，特征 较少，背景杂波会干扰目标检测，降低探测率。结合 探测模型中目标和背景的特点，分析背景杂波特性， 对其进行科学描述和量化，对优化系统设计、改进检 测算法、提高探测性能有重要意义。
ቤተ መጻሕፍቲ ባይዱ
频波动和传统分块尺度对杂波的影响。对遥感图像样本进行杂波量化和点目标检出仿真，结果表明本
文方法对杂波统计尺度有很好的稳定性，杂波量化与探测率的相关性高于传统方差统计方法。
关键词：杂波量化；点目标探测；像斑分布；匹配滤波器；探测率
中图分类号：TP391.41
文献标识码：A
文章编号：1001-8891(2018)04-0346-09