The Solar Radio Patrol Network of USAF and the Examination of Prediction Accuracy of the U-Shaped Radio Spectrum for Cycle 21

The solar radio patrol network of USAF is investigated, the discovery of the U-shaped radio specturm and the self-appraisal of the accuracy of predicting the proton events in Cycle 20 with the U-shaped spectrum by J.P.Castelii et al.are introduced in this paper.The prediction accuracy of the U-shaped spectrum is tested and verified with the proton events checked in the 21th cycle and a commentary on the prediction accuracy is also given here.