项目名称: 混合雷达中耦合扩展海杂波抑制技术研究
项目编号: No.51309232
项目类型: 青年科学基金项目
立项/批准年度: 2014
项目学科: 水利工程
项目作者: 肖卉
作者单位: 中国人民解放军空军预警学院
项目金额: 25万元
中文摘要: 混合雷达是采用天波雷达发射,地波雷达接收的工作模式,具有视距以外远程探测能力的新体制雷达。它在海事保障、国土安全等重要领域具有广泛应用价值,受到世界各发达国家高度重视。由于混合雷达采用特殊的工作模式,多种机理下产生的扩展海杂波相互耦合,严重遮盖弱小舰船目标影响检测。因此抑制耦合扩展海杂波已成为提高混合雷达检测性能必须突破的技术瓶颈。 根据对耦合扩展海杂波物理成因,以及大量实测数据的分析发现,其主成分的多普勒频谱特征主要有两类:耦合线谱特征和耦合宽带谱特征。因此本项目首先建立两类耦合多普勒频谱特征的模型和度量方法。在此基础上分两个方向进展。一是针对耦合线谱特征为主的信号,在非负矩阵分解(NMF)理论框架下,建立NMF海杂波抑制方法;二是针对耦合宽带谱特征为主的信号,引入分数阶傅里叶变换及其推广技术,建立分数阶域-NMF海杂波抑制方法。最后采用实测数据,验证两类NMF海杂波抑制技术的有效性。
中文关键词: 扩展海杂波;混合雷达;非负矩阵分解;分数阶傅里叶变换;
英文摘要: Hybrid radar is based on sky wave transmitting and surface wave Receiving. So hybrid radar has a wide coverage of detection and no range blind zone.However,due to complex factors, frist order bragg line is spread and coupled. And this will cause the neighboring target submerged. There are two features belonged to the coupled and spread sea clutter. One is coupled slice spectrum feature, the other is coupled wideband spectrum feature. Fristly, we establish two spectrum feature models with two coupled features. Secondly, we investigate NMF(Non-negative Matrix Fractorization) technology to improve the coupled slice spectrum feature extraction. And we investigate FRFT-NMF(Fractional Fourier Transform-NMF) to improve the coupled wideband spectrum feature extraction. At the end, we use real data to verify the improved technology. This item will play an important role in the development of hybrid radar and maritime safeguard.
英文关键词: Spread Sea Clutter;Hybrid Radar;Nonnegative Matrix Factorization;Fractional Fourier Transform;