外辐射源位置不确定时机载被动多基站雷达弱目标跟踪

As the newest development of the traditional Passive Multistatic Radar (PMR), the Airborne PBR (APBR) uses the airborne transmitter as the illuminator of opportunity, and has many advantages: covert, anti-stealth, low cost, easy deployment, high flexibility, good anti-interference and wide coverage. Consequently, the research on the APMR has important theoretical significance and application value. . In this proposal, we will research on the dim target tracking algorithm using APMR with uncertain transmitter location. Under the assumption that the exact transmitter location is not available, the research will focus on several key techniques. These techniques are listed as follows: clutter sparsity estimation for uniform and time-varying clutter, simultaneous estimation of target state and transmitter state with fluctuating SNR or diffused energy across range cells, 3D data association of “transmitter-target-measurement” in the Single Frequency Network (SFN), 3D tracking in the absence of elevation using a maneuvering receiver or multiple receivers by nonlinear fusion. In addition, taking the amplitude information into account, the Posterior Cramer-Rao Low Bound (PCRLB) will be derived in the presence of transmitter location uncertainty. And the trajectory of the receive will be optimized based on the Geometric Dilution of Precision (GDOP). Last, the proposed methods will be verified by numerical simulation and experiments. The results of the project can improve the tracking performance of the dim target with the APMR, and enhance the accurate level of the radar surveillance system.

机载被动多基站雷达（APMR）是一种全新体制的被动探测雷达，它利用机载外辐射源作为机会照射源，兼具隐身与反隐身能力，成本低，易部署，灵活性高，抗干扰性好，覆盖范围广，具有重要的理论研究意义和应用价值。. 本项目基于APMR，开展外辐射源位置不确定时的弱目标跟踪算法研究，重点突破在非合作机载外辐射源位置不确定情况下，杂波分布不均匀且时变时的杂波稀疏度估计、目标信号能量起伏或跨单元扩散时的目标与外辐射源状态联合估计、面向单频网的“外辐射源-目标-测量”三维数据关联、无俯仰测量时基于单站运动或多站非线性融合的三维跟踪等关键技术，推导外辐射源位置不确定时考虑幅度信息的状态估计最优理论性能界PCRLB，并基于几何精度因子GDOP，对机载接收站路径优化。最后，通过仿真和试验验证上述理论方法。通过本项目研究，可提高APMR对弱目标的跟踪性能，提高雷达探测系统的精细化水平。

本项目面向机载外辐射源被动多基站雷达探测系统，开展强杂波环境下扩展弱目标跟踪技术研究。主要研究内容包括：强杂波环境下机载外辐射源扩展目标航迹起始；基于高斯过程概率数据关联的跨单元扩展目标跟踪；机载外辐射源跨距离单元扩展目标状态估计的最优理论性能界。.项目执行期间，突破了如下关键技术：1）针对机载外辐射源被动多基站雷达探测系统跨距离单元扩展目标跟踪问题，首次提出考虑测量源不确定的条件下基于高斯过程的扩展目标跟踪算法，推导了扩展目标散射点个数与位置均未知条件下的关联事件后验概率密度，利用高斯过程，在线估计强杂波下星凸形状目标轮廓状态，并推导了测量源不确定时的扩展目标状态估计的信息缩放因子和后验克拉美劳下界PCRLB。2）针对机载外辐射源被动多基站雷达探测时杂波分布不均匀且密度未知的多目标跟踪问题，本项目提出一种基于稀疏度阶数优化的杂波密度估计算法，通过对杂波测量集中的“稀疏度阶数-超立方体容积”的样本拟合曲线求极值，在线优化杂波稀疏度阶数。3）针对杂波环境下多机动扩展目标跟踪问题，提出一种基于高斯过程的变结构多模型联合概率数据关联方法，通过在高斯过程中引入变结构多模型方法，实现多机动扩展目标的状态估计。.本项目所提出的方法能在非均匀、非平稳的复杂杂波环境下，利用机载外辐射源被动多基站雷达，在线估计探测区域内的杂波密度，同时实现多机动星凸形状目标运动状态和轮廓状态的联合估计，并给出杂波环境下扩展目标跟踪的最优理论性能界。本项目所取得的研究成果有助于提升我方军事防御系统对复杂战场环境的感知能力和对复杂形状目标的探测分类能力，为新一代防御系统的研制提供技术支撑。