Abstract:The global ionospheric model for longterm prediction and shortterm prediction was analyzed through dividing the vertical total electron content(VTEC)into deterministic component and signal component,fitting the filtered signal of autocovariance function using 4order autoregressive model,and using the LeastSquares Collocation method.The results show that correlation coefficient between longterm prediction of trend component and global ionospheric model of CODE is 0.812,and the residuals between model fitted values for daily mean global total electron content(mean global TEC,MGTEC)and reference values are less than 4 TECu.The results of shortterm prediction show that the prediction precision is lower in the Southern Hemisphere than that in Northern Hemisphere,and the prediction precision is the lowest in the region between 20°N and 20°S of geomagnetic equator and in the ocean areas.Global prediction precision RMS is about 1-7 TECu,the average precision is about 2.4 TECu in Northern Hemisphere,and is
about 3.5 TECu in Southern Hemisphere.