线加速度计在轨检测卫星影像颤振的可行性分析

Feasibility Analysis of Detecting Satellite Image Jitter On-orbit by Linear Accelerometer

线加速度计作为当前高分辨率光学卫星搭载的新型传感器,由于无法与相机焦平面固连,能否直接实现卫星影像颤振在轨检测是后续应用关键。针对上述不确定性问题,文章提出了基于视差成像的在轨分析与验证方法,即分别采用线加速度计颤振检测模型与视差成像颤振检测模型得到平台与焦平面颤振信息,进一步在轨道坐标系下进行频谱分析,验证线加速度计在轨检测卫星影像颤振的可行性。试验结果表明,两种检测模型得到的颤振主频频率与幅值基本一致,受多种因素影响,部分频段检测结果略有差异,线加速度计可直接用于颤振影像在轨检测与补偿。

As a new sensor on the high resolution optical satellite,the linear accelerometer can not be connected with the focal plane of the camera,therefore,it is critical for the satellite to directly detect the image jitter on orbit in the subsequent applications.In order to solve these uncertain problems,this paper proposes an on-orbit analysis and verification method based on parallax imaging,that is,using the linear accelerometer jitter detection model and the parallax imaging jitter detection model to obtain the platform and focal plane jitter information separately.Further,the spectrum analysis is carried out in the orbit coordinate system to verify the feasibility of the line accelerometer in detecting the jitter of satellite images on orbit.Experiments show that the jitter master frequency and amplitude of the two detection models are basically consistent with each other,although the results in some frequency bands are slightly different due to the influence of various factors.Accordingly,the linear accelerometer can be used directly in jitter image detection and compensation.