说明：  OMP算法的改进之处在于：在分解的每一步对所选择的全部原子进行正交化处理，这使得在精度要求相同的情况下，OMP算法的收敛速度更快。
(OMP algorithm improvement comprising: at each step of the whole atom decomposition of the selected orthogonal processing, which makes precision in the same circumstances, OMP algorithm converges faster.)