Based on arrearage character of speed

use excellent ability of forecast and fitting approximation of radial basis function（ RBF）

through network training and learning of speed values of known moment value of the next moment and it’s change trend can be well predicted. According to whether the value falling into the confidence interval caused by training error

judge and filter the outliers. Through experimental tests

95 %confidence interval can completely meet the function of eliminating abnormal data and keeping normal data.