TDI CCD相机大姿态角推扫成像行频精确匹配
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摘要
针对大视场TDI CCD相机大姿态角推扫成像过程中像面上像点像速差异较大,行频匹配精度不高引起的相机传函下降等问题,提出一种可支持粗调和精调的高精度行频匹配方法。首先,阐述了大视场遥感相机像速场的主要特点及像速匹配的关键问题;其次,深入分析了大视场TDI CCD相机大角度侧摆和前后摆推扫成像的像速场特性;然后,根据像速场特性制定同速匹配模式和异速匹配模式,分析传函特性,确定各自模式的使用条件;最后,提出了一种可支持粗调和精调的高精度行频匹配方法,并分析已实现行频匹配方法的精度,最终满足给定行频匹配精度要求。实验结果表明:在积分级数为96级,粗调方法使行频精度达到0.999 425,精调方法使行频精度达到0.999 928,2种方法均能使相机传函MTF优于0.998,从而实现大视场TDI CCD相机在各种大姿态角推扫成像条件下高质量成像。
With wide field of TDI CCD camera at the push of the attitude Angle of image point in the process of scanning imaging like speed difference is bigger,the row frequency matching precision is not caused by higher camera function to drop,a kind of coarse and fine adjustment precision horizontal frequency matching method was put forward.First of all,the large field of TDI CCD camera as the main characteristic of the velocity field and as the key problems of speed matching was expounded;Secondly,in the big field of TDI CCD camera Angle side swing and swing pushed sweeping imaging before and after in-depth analysis of the characteristics as velocity field;Then,according to the characteristics of the velocity field choose image speed matching mode of the same speed and the different speed,analysis the functional features,the using condition of each mode;Finally,this paper proposes a support of coarse and fine adjustment precision horizontal frequency matching method,and analysis of the accuracy of the implemented row frequency matching method,ultimately meet the requirements of a given row frequency matching accuracy.The experimental results show that the integral series for level 96,coarse adjustment method can make the precision of the row frequency 0.999 425,fine adjustment method can make the precision of the row frequency 0.999 928,two methods can make the camera pass letter MTF is better than 0.998,thus realize the wide field of TDICCD camera under the condition of all kinds of big push attitude Angle scanning imaging with high quality imaging.
With wide field of TDI CCD camera at the push of the attitude Angle of image point in the process of scanning imaging like speed difference is bigger,the row frequency matching precision is not caused by higher camera function to drop,a kind of coarse and fine adjustment precision horizontal frequency matching method was put forward.First of all,the large field of TDI CCD camera as the main characteristic of the velocity field and as the key problems of speed matching was expounded;Secondly,in the big field of TDI CCD camera Angle side swing and swing pushed sweeping imaging before and after in-depth analysis of the characteristics as velocity field;Then,according to the characteristics of the velocity field choose image speed matching mode of the same speed and the different speed,analysis the functional features,the using condition of each mode;Finally,this paper proposes a support of coarse and fine adjustment precision horizontal frequency matching method,and analysis of the accuracy of the implemented row frequency matching method,ultimately meet the requirements of a given row frequency matching accuracy.The experimental results show that the integral series for level 96,coarse adjustment method can make the precision of the row frequency 0.999 425,fine adjustment method can make the precision of the row frequency 0.999 928,two methods can make the camera pass letter MTF is better than 0.998,thus realize the wide field of TDICCD camera under the condition of all kinds of big push attitude Angle scanning imaging with high quality imaging.
引文
[1]荣少巍.基于FPGA的高精度多通道采集存储系统研究[J].电子测量技术,2014,37(4):108-112.
[2]武星星,刘金国.基于地球椭球的空间相机侧摆摄影像移补偿[J].光学精密工程,2014,22(2):351-359.
[3]王运,颜昌翔.基于差分法的空间相机像移速度矢量计算[J].光学精密工程,2011,19(5):1054-1060.
[4]金光,任秉文,钟兴.畸变对TDI-CCD空间相机的影响分析及抑制方法研究[J].光学学报,2013,33(10):221-227.
[5]王家骐,于平,颜昌翔,等.航天光学遥感器像移速度矢计算数学模型[J].光学学报,2004,24(12):1585-1589.
[6]聂品,田海英,董斌,等.矩形靶标测试CCD相机调制传递函数的研究[J].光学学报,2012,32(12):1204002.
[7]李晓云,杜伟.星载TDICCD相机像移对成像质量的影响分析[J].航天器工程,2011,20(3):51-55.
[8]李清军,刘志明,张雪菲,等.TDI CCD全景航空相机行转移信号产生方法[J].电子测量与仪器学报,2013,27(9):844-849.
[9]杨飞,金光,曲宏松,等.航天时间延迟积分CCD相机摆扫成像快速几何校正设计与分析[J].光学学报,2014,34(1):78-81.
[10]周翟和,汪丽群,沈超,等.基于CPLD的磁致伸缩高精度时间测量系统设计[J].仪器仪表学报,2014,35(1):103-108.
[11]李国宁,刘妍妍,张柯,等.高频差分采样技术在CCD信号处理中的实现[J].电子测量技术,2014,37(10):123-129.
[12]吕恒毅,刘杨,郭永飞.遥感相机焦面CCD机械拼接中重叠像元数的确定[J].光学精密工程,2012,20(5):1041-1047.
[13]郭汉洲,吕恒毅,曲利新.遥感相机动态调制传递函数与时间延迟积分CCD行周期误差的关系[J].光学精密工程,2013,21(8):2195-2200.
[14]武奕楠,张宇,韩双丽,等.长线阵TDI CCD空间相机像移匹配及MTF分析[J].电子测量技术,2014,37(10):71-75.
[2]武星星,刘金国.基于地球椭球的空间相机侧摆摄影像移补偿[J].光学精密工程,2014,22(2):351-359.
[3]王运,颜昌翔.基于差分法的空间相机像移速度矢量计算[J].光学精密工程,2011,19(5):1054-1060.
[4]金光,任秉文,钟兴.畸变对TDI-CCD空间相机的影响分析及抑制方法研究[J].光学学报,2013,33(10):221-227.
[5]王家骐,于平,颜昌翔,等.航天光学遥感器像移速度矢计算数学模型[J].光学学报,2004,24(12):1585-1589.
[6]聂品,田海英,董斌,等.矩形靶标测试CCD相机调制传递函数的研究[J].光学学报,2012,32(12):1204002.
[7]李晓云,杜伟.星载TDICCD相机像移对成像质量的影响分析[J].航天器工程,2011,20(3):51-55.
[8]李清军,刘志明,张雪菲,等.TDI CCD全景航空相机行转移信号产生方法[J].电子测量与仪器学报,2013,27(9):844-849.
[9]杨飞,金光,曲宏松,等.航天时间延迟积分CCD相机摆扫成像快速几何校正设计与分析[J].光学学报,2014,34(1):78-81.
[10]周翟和,汪丽群,沈超,等.基于CPLD的磁致伸缩高精度时间测量系统设计[J].仪器仪表学报,2014,35(1):103-108.
[11]李国宁,刘妍妍,张柯,等.高频差分采样技术在CCD信号处理中的实现[J].电子测量技术,2014,37(10):123-129.
[12]吕恒毅,刘杨,郭永飞.遥感相机焦面CCD机械拼接中重叠像元数的确定[J].光学精密工程,2012,20(5):1041-1047.
[13]郭汉洲,吕恒毅,曲利新.遥感相机动态调制传递函数与时间延迟积分CCD行周期误差的关系[J].光学精密工程,2013,21(8):2195-2200.
[14]武奕楠,张宇,韩双丽,等.长线阵TDI CCD空间相机像移匹配及MTF分析[J].电子测量技术,2014,37(10):71-75.