卫星导航服务的全球电离层时变特性分析

Analysis of temporal variation of global ionosphere based on IGS

针对电离层对无线电波应用技术的影响,该文利用IGS提供的1998年—2012年的全球电离层TEC数据,结合相应的太阳活动数据,采用时间序列分析、相关性分析以及等值线图等数理统计的方法,分析了全球电离层的时变特性;分析了电离层TEC、F10.7和太阳黑子数的相关性,发现3者之间的相关系数高度线性相关。通过电离层日变化规律的研究发现:电离层TEC日极大值出现的时刻集中在当地时间12时至16时,其中14时占38.47%,12时占26.58%,16时占19.05%;夜间TEC值与太阳活动强度密切相关,在太阳活动低峰年,夜间全球电离层TEC平均值在5TECU左右,在太阳活动高峰年,夜间全球电离层TEC平均值在17TECU左右,最大值可达24TECU。最后,从日地距离和太阳活动强度两个方面,讨论了全球电离层TEC季节变化规律以及成因。

Using global ionosphere TEC data from 1998 to 2012provided by IGS,combined with the corresponding data of solar activity,with the mathematical statistics methods of analysis of time series,correlation analysis and contour maps,the paper analyzed the global temporal characteristics of the ionosphere.First,it analyzed the correlation coefficients among TEC,F10.7index and sunspot,and found that the three have high linear correlation.Then,the diurnal variation of ionosphere was outlined as follows：daily maximum value of TEC mainly appeared from 12 hto 16hof the local time,in which 14 haccounted for 38.47%,12 haccounted for 26.58%,and 16 haccounted for 19.05%.Nocturnal TEC values were closely related to the intensity of solar activity.In the low solar activity years,the mean of global nocturnal TEC was about 5TECU,meanwhile,in the high solar activity years,the mean of global nocturnal TEC was about 17 TECU,and the maximum was 24 TECU.Finally,taking earth-sun distance and the intensity of solar activity into account,it analyzed the regularity and the causes of the global ionosphere TEC seasonal variation.