反射型超声衍射CT迭代重建算法

本文以傅立叶衍射定理为基础,将非均匀傅立叶变换和迭代法相结合,用正则化方法处理迭代的收敛问题,建立了反射型超声衍射成像算法。数据直接在频域中的非均匀频率点上比较,避免了频域内插引入的误差。本算法也减少了采样数据量,降低了运算的复杂度。实验结果表明,在迭代次数不多情况下,重建图像可以达到较好的视觉效果。

Iterative reconstruction algorithm for ultrasonic reflection mode diffraction tomography

Based on the Fourier diffraction theorem,a reflection mode diffraction tomography(RMDT) reconstruction algorithm is established based on the combination of the non-uniform fast Fourier transform(NUFFT) and an iterative method.A regularization method is used to ensure convergence of the iteration.With direct comparison of non-uniformly distributed frequency samples in the frequ-ency domain,errors due to the frequency domain interpolation are reduced.Also,the amount of sampled data needed in the reconstruction is decreased and computation complexity of the algor-ithm reduced.Experimental results show that,with a few iterative steps,the reconstructed image has acceptable visual quality.