最优抗干扰波形在线设计理论、方法与应用研究

Nowadays, with the development of electromagnetic countermeasure, it is very difficult for radar systems mounted on moving platforms to proble surface when the constantly changing EM environments are present. In this project, resorting to the idea of transmit-receive closed loop in cognitive radar, we present an on-line optimum waveform design technology which can be used to improve the radar systems' performance significantly. The designed optimum waveform can be used to suppress active interference, strong clutter and range sidelobe masking. Based on the two key problems including "optimum" and "on-line", we divide the research object into three facets including theoretical research, methodology research, and verification. We will study the dynamic properties of targets, interferences, and clutters, the operational modes of radar systems, and the Doppler mismatch effect. Consequently, the theoretical framework for optimum waveform design will be established. By adopting the constraints for practical use, the corresponding mathematical model of on-line waveform design will be provided. In order to eliminate the bottlenecks of "on-line", we will present several fast algorithms and parallel optimization strategies. The correctness and effectiveness of these algorithms will be demonstrated by using customized hardware verification platform. This project is valuable for theoretical research and engineering applications because it will provide new means for future radar systems to improve the capability of electronic countermeasures, and establish the theoretical foundation of cognitive radars working in complicated EM environments.

当前，复杂多变的电磁环境给运动平台上的雷达系统提出了巨大的挑战。本项目借助于认知雷达发射-接收闭环工作的思想，提出在线设计最优波形抑制有源干扰、强杂波和距离遮蔽干扰的技术，显著提高雷达的探测性能。本课题面向应用，围绕"最优化"和"在线"这两个关键问题，将主要研究内容分为理论研究、方法研究和试验验证三个主要方面。研究目标、干扰和杂波的动态特性，波形捷变雷达工作模式，多普勒失配影响等，建立最优波形在线设计抗干扰理论框架；充分考虑雷达实际工作中的约束限制，建立相应的数学优化模型，提出波形设计的快速算法和并行处理方案，突破"在线"设计与发生的技术瓶颈；搭建硬件仿真实验平台，验证理论和方法的正确性和实用性。本项目将为进一步提高雷达电子对抗能力提供新的技术手段，为研制适应复杂电磁环境下的认知雷达奠定理论和技术基础，具有重要的理论意义和工程应用价值。

当前，复杂多变的电磁环境给运动平台上的雷达系统带来了诸多挑战，杂波及有源干扰、旁瓣遮蔽、敌对截获等都成为影响雷达性能的因素。本项目借助认知雷达发射-接收闭环工作思想，围绕"最优化"和"在线"两个关键问题，以抑制有源干扰、强杂波和距离遮蔽干扰等突出问题入手，并开展抗干扰、抗截获、高多普勒容忍性波形设计等研究，提高雷达探测性能。本课题研究内容可分为理论研究、方法研究和试验验证三方面；研究目标、干扰和杂波的动态特性，多普勒失配影响等，建立最优波形在线设计抗干扰理论框架；充分考虑雷达实际工作中的约束限制，建立相应的数学优化模型，提出波形设计的快速算法和方案，突破"在线"设计的技术瓶颈；搭建硬件仿真实验平台，验证理论和方法的正确性和实用性。第一，依托多传感器辅助知识来设计波形，提出纯相位谱逼近低旁瓣波形设计算法、局部正交波形对设计方法等交替投影算法框架，进而提出一系列高性能松弛交替投影算法框架，摆脱了常规方法鲁棒性差、耗时长等困境；第二，针对动目标探测波形多普勒容忍性差、旁瓣高、抗截获特性差等问题，从噪声雷达思想出发构造线性调频复合波形，提出联合优化相位修正及松弛交替投影的波形设计算法，提高探测波形性能；第三，深入分析实测数据，完成了对杂波、目标的合理性建模，提出基于最大后验概率估计和广义似然比检验的极化检测器、基于失配滤波器设计与在线抗干扰波形设计的检测框架等方法、方案，进一步提高目标检测性能；第四，从多传感器建模与信息融合思想入手，提出基于多模型融合的机动目标认知跟踪-抗干扰波形设计方法，提高了机动目标跟踪性能。本项目将为进一步提高雷达电子对抗能力提供新的技术手段，为研制适应复杂电磁环境下的认知雷达奠定理论和技术基础，具有重要的理论意义和工程应用价值。