分析了三线阵立体测绘相机成像原理,针对三线阵立体测绘相机在对地成像过程中存在的前视、正视和后视相机像移速度和偏流角的差异,推导了基于地球椭球的前视、正视和后视相机像移速度和偏流角计算公式.以某三线阵立体测绘相机为例,选取WGS84地球椭球模型,分析了前视相机和后视相机都以正视相机为准调整行周期和偏流角时,像移速度匹配残差和偏流角残差对像质的影响.分析及实验结果表明,以调制传递函数下降5％为约束,当积分级数＞2时,应分别调整前视、正视和后视相机的行周期;按正视相机调整前视相机和后视相机的偏流角时,积分级数应取40级以内.%The imaging principles of a three-line stereo mapping camera was analyzed. To overcome the differences of image motion speeds and drift angles of the forward-view camera, nadir-view camera and backward-view camera, the calculation formulas of image motion speeds and drift angles for forward-view, nadir-view and backward-view cameras based on an ellipsoid model were deduced. By taking a three-line stereo mapping for an example and using the WGS84 earth ellipsoid model,the influences of image motion speed matching remains and drift angle remains on the image quality of a three-line stereo mapping camera were analyzed when the forward-view and backward-view cameras both adjust the row transfer periods and drift angles same as the nadir-view camera. Results indicate that with 5 % reduction of MTF as a constraint, if more than 2 TDI stages are used nadir-view camera, the forward-view and backward-view cameras should adjust their row transfer periods respectively; However, if drift angles of forward-view and backward-view cameras are adjusted according to nadir-view camera, TDI stages should be no more than 40.
展开▼
