基于分布式天线的宽带相位测距机制与方法研究

In order to solve the problems of phase unwrapping，low signal-to-noise ratio and the fluctuant RCS with time which cause the accuracy decrease in the phase measurement system of the cooperative high dynamic target, a mechanism of wide-band measurement system by phase based on distributed antenna is proposed. This project carries out the layout of wide-band measurement system by phase based on distributed antenna and the design of signal waveform, and analyzes the ranging precision influence caused by the target's maneuverability, sparse distribution characteristics and the position precision of antenna. The measurement matrix signal model of distributed antenna and the precision analysis model for ranging are established based on the target motion trajectory. On this basis, the signal processing methods according to high precision measurement system by phase based on distributed antenna are developed, the three-dimensional reconstruction algorithm based on sparse signal processing is researched, thus the relative position relations between observed object and radar is obtained. Meanwhile, the performance evaluation model of the system is established, and the performance evaluation and the algorithm optimization of range measurement by means of NESZ, Cramer-Rao bound and so on are developed. The efficacy of the mechanism and method are verified by numerical simulation and simulation experiment, the signal processing method is optimized, so that the the ranging precision can be improved. This project will provide a new method and technical support to the application of radar range measurement by phase.

针对非合作式高动态目标相位测距系统中相位解模糊、目标低信噪比以及雷达散射截面积(RCS)随时间起伏等导致测量精度降低的一系列问题，提出基于分布式天线的宽带相位测距机制。本项目主要开展基于分布式天线的宽带相位测距天线布局与波形设计，分析目标运动机动特性、稀疏分布特性和天线位置精度等对测距性能的影响,建立基于目标运动轨迹和观测矩阵的分布式天线测距信号模型和测距精度分析模型；在此基础上，发展针对分布式天线高精度相位测距的信号处理方法，研究基于稀疏信号处理的目标三维重建算法，获取观测目标与雷达之间的精确相对位置关系；建立系统性能评估模型，结合系统噪声等效后向散射系数（NESZ）和克拉美罗界等手段开展测距性能评估与算法优化研究；通过数值仿真和地面模拟试验验证模型与方法的有效性，优化信号处理方法，提高测距精度，为雷达相位测距技术的应用提供一种新的方法与技术支撑。

针对我国导弹、临近空间飞行器、空间航天器高精度目标测量和识别领域存在的相位解模糊、目标低信噪比以及雷达散射截面积(RCS)随时间起伏等导致测量精度降低、识别能力有限等一系列问题，提出基于分布式天线的宽带测量机制。结合宽带数字化分布式雷达体系架构，开展了基于分布式天线的宽带相位测距天线布局与波形设计，分析目标运动机动特性、稀疏分布特性和天线位置精度等对测距性能的影响,建立了基于目标运动轨迹和观测矩阵的分布式天线测距信号模型和测距精度分析模型。在此基础上，开展了分布式阵列雷达信号处理新理论与新方法研究：①实现基于混沌波形的抗干扰波形设计，利用Lorenz混沌系统实现了分布式正交波形产生与模拟；②开展了基于分布式宽带雷达的探测跟踪技术研究，给出雷达波形、工作模式和资源调度等最优设计，形成群目标分辨、检测与参数估计新理论；③提出基于阵面回波相关的分布式测角技术和基于频域补偿的非线性失真矫正技术，解决传统和差测角存在的问题，实现了宽带信号的高精度测角；④提出了基于频域处理的宽带雷达回波微多普勒信号处理方法，解决了低重频条件下的微多普勒解模糊难题，实现了宽带雷达回波的微动特征提取；⑤提出了基于稀疏信号处理的目标三维重建方法，突破了大稀疏阵列栅瓣抑制和分布式阵列幅相一致性技术，实现在单个脉冲周期内对目标的瞬态探测及三维成像。通过数值仿真和地面模拟试验验证模型与方法的有效性，优化信号处理方法，提高测距精度，为基于分布式阵列雷达新体制的目标检测、跟踪、运动参数测量以及高精度成像等提供技术支撑。本项目提出了的一种全新的宽带脉冲雷达测量机制，其理论研究成果在临近空间飞行器目标特性测量、导弹航天测控、战略预警、空间目标监视等领域具有良好的经济军事效益和广泛的应用前景。