面向雷达侦察的先验波形信源波达方向估计技术研究

To handle the increasingly complex battlefield electromagnetic environment, modern radar reconnaissance system is required to deal with direction finding of simultaneous multiple signals and even simultaneous multiple signals belonging to same frequency band. Considering the characteristics of the knowledge base of the radar reconnaissance system, the direction of arrival (DOA) estimation technology for prior waveform source can effectively meet the direction finding requirement of the radar reconnaissance system. However, due to non-ideal factors such as imperfect pulse arrival time estimation, high-speed motion of the platform, and inaccurate prior waveform information, there is a difference between the actual detected radar signal and the prior waveform information in the radar reconnaissance system knowledge base. The DOA estimation methods with prior waveform information available cannot be applied directly. In order to meet the direction finding requirements of the radar reconnaissance system, three aspects will be investigated in sequential manner based on the complexity of application scenarios, i.e., DOA estimation of the non-synchronous ideal prior waveform sources and DOA estimation of the non-synchronous prior waveform sources with Doppler effect, DOA estimation of the non-synchronous prior waveform sources with unknown bias. The project will make up for the lack of research on the existing DOA estimation methods of prior waveform sources, provide a solid theoretical support for the application of prior waveform source DOA estimation techniques to radar reconnaissance, and broaden the application fields of prior waveform source DOA estimation technology.

日益复杂的战场电磁环境要求现代雷达侦察系统必须具有同时乃至同频同时多信号测向能力。考虑到雷达侦察系统具有知识库的特点，先验波形信源波达方向估计技术可以有效地满足雷达侦察系统的测向需求。然而，由于脉冲到达时间估计不准、平台高速运动、先验波形信息不准确等非理想因素，实际侦收的雷达信号与雷达侦察系统知识库内的先验波形信息存在差异，现有先验波形信源波达方向估计技术无法直接应用。为满足雷达侦察系统的测向需求，本项目依场景复杂程度逐步递进地开展非同步理想先验波形信源波达方向估计技术、存在多普勒效应的非同步先验波形信源波达方向估计技术和存在未知偏差的非同步先验波形信源波达方向估计技术三个方面研究，以期弥补现有先验波形信源波达方向估计技术研究的不足，为先验波形信源波达方向估计技术在雷达侦察中的应用提供坚实的理论支撑，拓宽先验波形信源波达方向估计技术的应用范围。

随着我国综合实力的不断上升，周边安全形势日趋复杂。大力发展雷达侦察对于维护国家安全具有重要战略意义。随着战场用频设备数量急剧增加，同时乃至同频同时多信号测向能力对现代雷达侦察系统至关重要。本项目充分考虑到雷达侦察系统具有知识库的特点，结合具有同时多信号测向能力的空间谱估计技术，重点关注脉冲到达时间估计不准、平台高速运动、先验波形信息不准确等非理想因素影响，提出基于正交投影理论的多参数非线性去耦方法与匹配滤波降维技巧，高效解决了非同步理想先验波形信源波达方向估计。进一步提出了基于拓普利兹占优准则的存在多普勒效应的非同步先验波形信源低计算复杂度波达方向估计方法，具有中高信噪比下可达克拉美罗界的优异性能。同时，利用交替迭代优化策略实现了存在未知偏差的非同步先验波形信源波达方向估计。此外，本项目还扩展了研究内容，通过构建混合代价函数、广义l2-lp最小化等手段，解决了冲激噪声背景下先验波形信源波达方向估计。项目研究成果丰富了现有先验波形信源波达方向估计技术的研究，可为先验波形信源波达方向估计技术在雷达侦察中的应用提供坚实的理论支撑。