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The high speed of low earth orbit (LEO) satellites makes the terminals at eachbeam tend to switch rapidly and frequently. The predictable trajectories of LEO satellites al?low for predictable terminal switching, therefore a simple and highly accurate orbit predic?tion model is required to swiftly obtain accurate switching time. This study utilizes the sim?plified general perturbations (Version 4) (SGP4) model to predict the LEO satellite trajecto?ry of WT-1, an LEO satellite developed independently by the 54th Research Institute of Chi?na Electronics Technology Group Corporation (CETC). The obtained prediction results are compared with the actual telemetry data of the WT-1, which gives the accuracy of the SGP4 predicted satellite trajectory within 1 km. The terminal entry/exit beam timing is simulated by using the SGP4 model-predicted orbit and the satellite's own telemetry data. The simula?tion result shows that the error between the SGP4 model-predicted terminal entry/exit beam timing and the actual timing is less than 1 s. The influence of terminal motion on prediction is discussed. The results show that the error caused by the movement of the ground terminal on the prediction is less than 0.687 s, and the SGP4 model has a definitely practical value for terminal switching determination in the LEO constellation.