针对在地面站天线对空间站观测任务中,通常基于卫星工具包(satellite tool kit,STK)软件规划出天线对空间站的方位角和俯仰角,实现天线对空间站的自动跟踪.为了保证天线跟踪的准确性和可靠性,需要定期计算出准确的空间站轨道和天线的方...针对在地面站天线对空间站观测任务中,通常基于卫星工具包(satellite tool kit,STK)软件规划出天线对空间站的方位角和俯仰角,实现天线对空间站的自动跟踪.为了保证天线跟踪的准确性和可靠性,需要定期计算出准确的空间站轨道和天线的方位俯仰角,并更新规划任务.因此科学分析与评估空间站两行轨道根数(two line elements,TLE)长期预报精度,对地面站实现空间站的精准跟踪具有重要意义.本文以中国空间站(China Space Station,CSS)梦天实验舱为例,基于TLE数据,利用STK软件提供的简化常规摄动规模型(simplified general perturbations4,SGP4)模型计算空间站轨道以及空间站相对于西安地面站的方位角和俯仰角,并分析不同策略下的精度效果.试验结果表明:在第二天更新空间站的TLE,可以获得较好的轨道结果,从而更好地保障天线的跟踪精度.展开更多
The high speed of low earth orbit(LEO) satellites makes the terminals at each beam tend to switch rapidly and frequently.The predictable trajectories of LEO satellites allow for predictable terminal switching,therefor...The high speed of low earth orbit(LEO) satellites makes the terminals at each beam tend to switch rapidly and frequently.The predictable trajectories of LEO satellites allow for predictable terminal switching,therefore a simple and highly accurate orbit prediction model is required to swiftly obtain accurate switching time.This study utilizes the simplified general perturbations(Version 4)(SGP4) model to predict the LEO satellite trajectory of WT-1,an LEO satellite developed independently by the 54th Research Institute of China 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 simulation 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.展开更多
SGP4(Simplified General Perturbations Model 4)是用于预测近地轨道卫星位置和速度的标准模型。本研究旨在评估SGP4模型的精度,通过对比SGP4预测轨道与高精度轨道预报数据,分析其误差随时间和轨道高度的变化,使用STK进行仿真验证,讨...SGP4(Simplified General Perturbations Model 4)是用于预测近地轨道卫星位置和速度的标准模型。本研究旨在评估SGP4模型的精度,通过对比SGP4预测轨道与高精度轨道预报数据,分析其误差随时间和轨道高度的变化,使用STK进行仿真验证,讨论影响轨道模型精度的主要因素。结果表明,SGP4模型的精度随轨道高度的降低而降低,误差主要由SGP4模型中简化的地球引力场和大气模型引起。当轨道高度高于500km时,SGP4模型能够满足大规模星座管理和实时应用的轨道预报精度要求。展开更多
文摘针对在地面站天线对空间站观测任务中,通常基于卫星工具包(satellite tool kit,STK)软件规划出天线对空间站的方位角和俯仰角,实现天线对空间站的自动跟踪.为了保证天线跟踪的准确性和可靠性,需要定期计算出准确的空间站轨道和天线的方位俯仰角,并更新规划任务.因此科学分析与评估空间站两行轨道根数(two line elements,TLE)长期预报精度,对地面站实现空间站的精准跟踪具有重要意义.本文以中国空间站(China Space Station,CSS)梦天实验舱为例,基于TLE数据,利用STK软件提供的简化常规摄动规模型(simplified general perturbations4,SGP4)模型计算空间站轨道以及空间站相对于西安地面站的方位角和俯仰角,并分析不同策略下的精度效果.试验结果表明:在第二天更新空间站的TLE,可以获得较好的轨道结果,从而更好地保障天线的跟踪精度.
文摘The high speed of low earth orbit(LEO) satellites makes the terminals at each beam tend to switch rapidly and frequently.The predictable trajectories of LEO satellites allow for predictable terminal switching,therefore a simple and highly accurate orbit prediction model is required to swiftly obtain accurate switching time.This study utilizes the simplified general perturbations(Version 4)(SGP4) model to predict the LEO satellite trajectory of WT-1,an LEO satellite developed independently by the 54th Research Institute of China 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 simulation 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.
文摘SGP4(Simplified General Perturbations Model 4)是用于预测近地轨道卫星位置和速度的标准模型。本研究旨在评估SGP4模型的精度,通过对比SGP4预测轨道与高精度轨道预报数据,分析其误差随时间和轨道高度的变化,使用STK进行仿真验证,讨论影响轨道模型精度的主要因素。结果表明,SGP4模型的精度随轨道高度的降低而降低,误差主要由SGP4模型中简化的地球引力场和大气模型引起。当轨道高度高于500km时,SGP4模型能够满足大规模星座管理和实时应用的轨道预报精度要求。
