基于压缩感知的外辐射源高分辨雷达算法及其应用研究

There are various kinds of interference in the echo antenna of passive radar. In order to avoid the noise of the moving target, it is necessary to filter the received signal to improve the signal to noise ratio (SNR). In order to achieve high Doppler resolution, a long range time is needed to accumulate the received signal, and a multi band joint method is used to obtain a higher range resolution. However, long time accumulation will cause the range migration and Doppler migration, and multi band joint will bring frequency gap problem. The emergence of compressed sensing algorithm makes the processing of above problems simplified. There is a big difference between the signal processing in the compressed sensing radar system and the traditional methods, such as the need for a separate clutter suppression step. It is possible to achieve higher resolution, and help to locate and more advantages. Therefore, the radar signal processing based on compressed sensing is considered to be a promising research direction. Benefited from the performance advantage of passive radar fully, this project will extend the existing system function and enhance the ability to detect moving targets. Moreover, the researchers will systematically carry out high resolution digital TV signal based on signal processing theories and methods of passive radar. The research results will promote the development of China digital TV passive radar, which has important theoretical significance and practical value.

外辐射源雷达的回波天线中包含各种干扰，为避免运动目标被遮掩，需要对所接收的信号进行滤波，提高信噪比。为实现高多普勒分辨率需要对接收信号进行长时间积累，并采用多频带联合的方法获得更高的距离分辨率。但长时间积累则会造成距离徙动和多普勒徙动，多频带联合则会带来频率间隙问题。压缩感知算法的出现则使这三个问题的处理变得简化。在压缩感知雷达体制下的信号处理与传统方法有较大的差异，例如无需单独的杂波抑制步骤，有可能实现更高的分辨率，有助于定位等多方面优势。因而，基于压缩感知的外辐射源雷达信号处理被认为是一个非常有潜力的研究方向。本项目充分利用外辐射源雷达的性能优势，扩展已有系统功能，提升对运动目标的探测能力，系统而深入地开展基于数字电视信号的高分辨率外辐射源雷达信号处理理论和方法。研究成果将促进我国数字电视外辐射源雷达的发展，具有重要的理论意义和实用价值。

基于压缩感知的外辐射源雷达信号处理被认为是一个非常有潜力的研究方向。本项目充分利用压缩感知理论的优势，开展高分辨率外辐射源雷达信号算法及其应用研究。主要研究成果包括：（1）压缩感知理论：对贪婪算法和稀疏贝叶斯学习算法进行改进，充分利用结构稀疏性提高算法的重构准确度，并设计快速的计算方式保证算法的高效率。（2）外辐射雷达信号处理方法：对外辐射源雷达信号进行稀疏表示，将压缩感知理论应用于杂波抑制、长时间积累、多频带联合，实现了高分辨率外辐射源雷达的距离多普勒处理。（3）高分辨应用：对目标成像和目标识别这两种外辐射源雷达的新兴应用领域进行了初步尝试。上述三部分内容相关研究成果的正确性和有效性均采用仿真结合实测数据处理的方式进行了验证。