SGP4/SDP4模型预报可靠性分析

Tests of the Accuracies of SGP4/SDP4 Model Predictions

以激光测距资料精密定轨结果为参考轨道,分析了两种典型版本SGP4/SDP4模型对低、中、高轨道卫星预报误差的放大规律,当预报超过一定的圈数后误差成指数增长。数值试验结果表明:对低、中、高轨卫星预报误差无显著放大圈数分别是(h≤300 km),40;(300 km≤h≤1 200 km),150;(1 200 km≤h≤10 000 km),300;半同步卫星(19 000km≤h≤22 000 km),55;同步卫星(33 000 km≤h≤38 000 km),10。并图示出参考卫星轨道预报误差的放大规律,供工程中利用双行根数和SGP4/SDP4模型作轨道预报时参考。

We analyze increasing variations of errors in two typical versions of the SGP4/SDP4 model for different orbits by taking orbits precisely determined with SLR as references. The errors grow exponentially after a few orbital periods. Numerical results show that for the low-, medium-, and high-earth orbits the numbers of orbital periods without significant errors from predictions are＇40（ h ≤300 km） , 150 （300 km ≤ h ≤ 1 200 kin）, 300（ 1 200 km≤h≤ 10 000 kin）, 55 （ semi-synchronous orbit; 19 000 km≤h≤22 000 km）, and 10（geosynchronous orbit; 33 000 km≤h ≤ 38 000 km） . The plots about error variations in this paper give references for engineers for predicting satellite orbits with the TLE and SGP4/SDP4 models.