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电离层ＣＴ技术中由于数据采集系统的几何结构存在局限性，致使探测所得数据不完全，导致其成为不完全数据重建问题（有限角度层析）。投影中的采样点不均匀，且由投影谱通过Ｆｏｕｒｉｅｒ中心切片原理组合而得的二维谱平面不完全可知，若要用变换方法重建成象，需要对其进行估计。可以利用小波外推方法估值，但是小波函数的选择具有多样性，文中选用比较常用的Ｍｅｘｉｃｏ 草帽小波进行外推。给出了必要的推导过程和数值模拟结果。
Due to the limitation of the geometric structure of the data acquisition system in the ionospheric CT technique, the data obtained by the detection are not complete, which leads to the problem of incomplete data reconstruction (limited angle tomography). The sampling points in the projection are not uniform, and the two-dimensional spectrum plane obtained by the combination of the projection spectrum and the Fourier center slice principle is not completely known. To reconstruct the image by the transformation method, it needs to be estimated. We can use the wavelet extrapolation method to estimate, but the choice of wavelet function is diversified. In this paper, the commonly used Mexico straw hat wavelet extrapolation. The necessary derivation process and numerical simulation results are given.