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基于合成孔径激光成像雷达(SAIL)二维数据收集方程和成像算法,研究了圆形孔径和矩形孔径光学望远镜天线的方位向成像分辨率,导出了点扩展函数的解析表达式,分析了理想成像点尺寸及其光学足迹中心偏离、相位二次项匹配滤波失匹、空间采样宽度、采样周期等的影响;也研究了距离向成像分辨率并分析了非线性啁啾补偿等的影响。对于各种影响因素都给出了数学判据,特别是发现了矩形孔径的光学望远镜可以产生适合于SAIL扫描方式的矩形光学足趾并消除方位向分辨率不均匀降低,可以设计最佳的矩形孔径的尺度分别控制光学足趾在方位向及其垂直方向上的尺度,得到大扫捕宽度和高方位向分辨率;也发现了目标外差延时必须尽量小以克服非线性啁啾和初始光频不稳定性相位误差。
Based on the two-dimensional data collection equation and imaging algorithm of synthetic aperture laser imaging radar (SAIL), the azimuthal imaging resolution of circular aperture and rectangular aperture optical telescope antenna was studied and the analytic expression of point spread function was derived. The ideal imaging Point size and its optical footprint center mismatch, phase quadratic term matching filter loss, spatial sampling width, sampling period and so on; also studied the distance imaging resolution and analyzed the nonlinear chirp compensation and so on. Mathematical criteria are given for various influencing factors. In particular, it is found that a rectangular aperture optical telescope can produce a rectangular optical toe suitable for the SAIL scanning mode and eliminate an uneven reduction of the azimuth resolution, so that an optimal rectangle can be designed The aperture scale controls the dimensions of the optical toe in azimuth and in the vertical direction, respectively, resulting in large sweep width and high azimuth resolution. It is also found that the target heterodyne delay must be as small as possible to overcome the nonlinear chirp and initial Optical frequency instability phase error.