【作者】 马静；

【导师】 刘宏伟；

【作者基本信息】 西安电子科技大学 ， 信号与信息处理， 2010， 硕士

【摘要】 当前空间技术迅猛发展,现代战争对空间依赖性增强,人类航天活动增加,空间目标监视和识别变得尤为重要。现役的空间目标特性测量雷达大多属于低分辨窄带雷达,虽然其信息量有限,但造价相对低廉,目前仍是一种主要的空间目标探测传感器。对窄带雷达来说,虽然其距离分辨率较低,但受不同目标散射特性的影响,不同目标间的回波包络会有一定差异,这一差异信息可以用于实现目标识别。对空间目标,由于其运动有自身的规律,不像飞机等目标相对于雷达的姿态变化具有较大不确定性。因此,采用窄带雷达对空间目标进行识别具有较大实用价值,这也是本文研究的出发点。本文研究了空间目标的雷达回波特性和识别方法,分析了窄带雷达实测数据的分布情况,然后对其提取具有平移不变性的中心矩特征。再分别用主成分分析法(PCA)和Fisher线性判别法(FLD)对中心矩特征进一步选择,最后分别用最小欧氏距离法和支持向量机(SVM)对空间目标分类识别。通过实测数据的实验结果验证了利用雷达回波包络差异识别空间目标是可行的。更多还原

【Abstract】 Currently, rapid and drastic changes are taking place in the space technology. With the reinforcement of depending on space in modern wars and the development of spaceflight activity of human, the surveillance and recognition of space targets become especially important. Most of active radars, used to measure target’s characteristic, belong to low-resolution narrowband radar. The information obtained by low-resolution narrowband is limited, but it was still a main sort of space target detect sensor for low cost. The range resolution of narrowband radar is low. Influenced by different target scattering characteristics, there are differences in echo envelop of different targets, which could be used for target recognition. The movement of space target is regular, so variation of its pose is certain. The research starting point of this thesis lies that satisfactory results can achieved by using narrowband radar to recognize space target.In this thesis, the radar echo characteristic and the identification of space target are studied, and the distribution of measured data is analyzed. Their central moment’s features, with translation-invariant property, are calculated for further recognition. Then Principle Component Analysis (PCA) and Fisher Linear Discriminant (FLD) are respectively used to choose the central moment feature. Finally, the Least Euclidean Distance and a multi-class support vector machine (SVM) classifier are respectively designed to classify space targets. The experimental comparisons based on measured satellites data show that the space target can be recognized by utilizing its radar echo envelop.更多还原