基于上述原子搜索原理，提出一个简单的想法，采用“大步长快速接近、小步长逐步逼近”的策略来重构信号，对FBP算法进行改进，即改变其前向步长和后向步长-Based on the above search atomic theory, put forward a simple idea, a "big long fast approaching, gradually approaching small step" strategy to reconstruct the signal, FBP algorithm is improved, ie change its forward and backward step step long