运动补偿用惯性器件误差对SAR成像分辨率的影响研究

 为提高合成孔径雷达（SAR）系统的性价比，必须根据SAR成像分辨率的要求和整体系统参数，设计相应精度的运动补偿用捷联惯导系统。在确定SAR运动补偿系统方案和安装方式的基础上，分析不同方向的加速度计和陀螺仪误差对天线相位中心位置测量误差的影响，并利用位置测量误差与SAR成像分辨率之间的关系，进一步明确了不同方向的加速度计和陀螺仪对SAR成像分辨率的影响。研究表明：基于SAR的工作原理和安装方式，x方向加速度计和y方向陀螺仪对SAR成像分辨率的影响明显比其他惯性器件严重；相同误差水平的惯性器件对SAR成像分辨率的影响随着合成孔径时间和工作波长的不同而不同，时间越长，波长越短，影响则越严重。SAR成像仿真证明了结论的正确性。研究结果对于研制高性价比SAR成像运动补偿系统有一定的理论指导意义。

Study on Effect of Inertial Device Error in Motion Compensation Subsystem on SAR Image Resolution

This paper explores the relationship between inertial device error and synthetic aperture radar(SAR)image resolution in order to improve the performance and cost ratio of SAR motion compensation system.The relationship will help the researchers to develop the SAR motion compensation subsystem with corresponding precision.First this paper describes the solution and fixing way of SAR motion compensation subsystem,and then figures out the different influence of inertial device error(on different axes)on antenna position measurement precision.Finally the relation between SAR image resolution and inertial device error is established by taking advantage of the relation between SAR image resolution and antenna position measurement error.From the analysis and emulation it can be seen that the accelerometer on x-axis and the gyro on y-axis are much more important than other inertial devices for SAR image resolution.However,even though inertial devices with same accuracy are used different SAR wave lengths and coherent times will cause different image resolutions.Emulations of SAR image of single point target verify the above conclusions.