利用北斗GEO卫星观测监测深圳市周围地区电离层空间环境

Observations of Ionospheric Space Environment Around Shenzhen with BeiDou GEO Satellite

采用非差非组合精密单点定位(precise point positioning,PPP)反演北斗GEO卫星穿刺点位置的垂直方向电子总含量(vertical total electron content,VTEC),利用GEO卫星在时域上穿刺点位置近似固定的特性,反演、分析了深圳市2020年的电离层空间环境参数,并详细评估了该区域VTEC实测值与国际GNSS服务(International GNSS Service,IGS)组织提供的全球电离层模型(global ionosphere model,GIM)电离层产品间的差异。结果表明:在深圳市,北斗GEO卫星的VTEC实测值与GIM产品具有较好的一致性,全年差值的日均值和标准差分别为-0.87 TECU和3.24 TECU,各月份差值的日间时段均值略小于夜间时段,差值的标准差呈现明显的季节性特性,其中,6月、7月、8月份较低。整体上,GIM的VTEC日峰值比实测值的小,全年差值的均值和标准差分别为3.51 TECU和5.98 TECU。

The vertical total electron content(VTEC)of puncture point of BeiDou GEO Satellite is obtained by non-different and non-combined precise point positioning(PPP).Utilizing the characteristic that the location of GEO satellite puncture point is approximately fixed in the time domain,we retrieve and analyze the ionospheric space environment parameters in Shenzhen in 2020.And the differences between measured VTEC and global ionosphere model(GIM)products provided by International GNSS Service(IGS)are evaluated in detail.The results show that the measured VTEC values of BeiDou GEO satellites in Shenzhen have good consistency with GIM products.The daily mean and standard deviation of annual differences are-0.87 TECU and 3.24 TECU,respectively.The mean values of monthly differences in daytime are slightly smaller than those in night time,and the standard deviation of differences presents obvious seasonal characteristics,which is lower in June,July and August.Compared to the daily VTEC peak values of measured values,the daily VTEC peak values of GIM are smaller overall,with the mean and standard deviation of annual difference values 3.51 TECU and 5.98 TECU,respectively.