高速俯冲前视线阵SAR三维高分辨成像技术研究

High-speed diving forward-looking linear-array synthetic aperture radar (SAR) has become one of the most attractive radar techniques because it can provide navigation and target information for aircraft blind landing and battle reconnaissance, which can work day and night nearly under all weather conditions. The development of high-speed diving forward-looking linear-array SAR has strategic significance for improving the ability of disaster assistance and the modernization of national defense technology. For the problems caused by the diving platform, such as serious 3D coupling and nonlinear space-variant of Doppler frequency modulation rate, based on the detailed analysis on movement characteristic of the high-speed diving forward looking linear-array SAR platform, this project will build the target echo signal model, propose the 3D de-coupling method, Doppler FM rate nonlinear space-variant compensation method and sensing matrix adaptive optimization method to realize 3D forward-looking imaging, which may utilize fractional Fourier transform (FrFT), compressive sensing and adaptive signal processing theory. This project will establish the new 3D forward looking imaging theory for high-speed diving linear array SAR, which can improve the reliability of aircraft blind landing, acquire battlefield information and so on.

高速俯冲前视线阵SAR可全天时全天候为飞机盲降、战场侦察提供三维高精度导航与目标信息，是雷达成像领域的研究热点。发展高速俯冲前视线阵SAR成像技术对提升我国灾害救援能力和实现国防科技现代化具有重要的战略意义。针对平台俯冲运动引起的三维耦合严重、多普勒调频斜率非线性空变等问题，本项目将在充分调研分析高速俯冲前视线阵SAR平台运动特点的基础上，结合分数阶傅里叶变换、压缩感知和自适应信号处理等先进信号处理理论，建立目标回波信号模型，提出三维解耦合方法、多普勒调频斜率非线性空变补偿方法以及传感矩阵自适应优化方法，从而实现对前视目标区域的三维高分辨成像。本项目的研究将建立高速俯冲前视线阵SAR三维成像新理论，为提高飞机盲降可靠性和获取战场信息提供新的解决思路和理论依据。

高速俯冲前视线阵SAR可全天时全天候为飞机盲降、战场侦察提供三维高精度导航与目标信息，是雷达成像领域的研究热点。发展高速俯冲前视线阵SAR成像技术对提升我国灾害救援能力和实现国防科技现代化具有重要的战略意义。本项目围绕平台俯冲运动引起的三维耦合严重、多普勒调频斜率非线性空变等关键科学问题，开展了以下研究工作：在分析高速俯冲前视线阵SAR平台运动特点的基础上，建立了高速俯冲前视线阵SAR三维成像场景几何模型和回波信号模型；提出一种适用于高速俯冲前视线阵SAR的RD和NLCS三维成像算法；提出基于TSVD和传感矩阵自适应优化的切航向高分辨成像算法，实现了阵列长度受限情况下的高速俯冲前视线阵SAR三维成像。通过本项目的研究，可为高速俯冲前视线阵SAR三维成像提供新的技术手段，为新型成像雷达的研制和应用提供理论与方法支撑。