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  • 2006年12月13日太阳射电暴对GPS系统完整性和连续性的影响

    Subjects: Geosciences >> Space Physics submitted time 2017-01-22

    Abstract: Solar activity and Earth's space environment can effect the operation and safety of spacecraft, and they are also the main error source of navigation, positioning, and communication based on radio waves applications system. In this field, the L-band solar radio burst is regarded as a potential threat to Global Navigation Satellite System(GNSS) stability and performance. When the solar radio burst exceeds a threshold value, the radio noise from solar emission will increase dramatically, which can give rise to GNSS receiver tracking loss and positioning failure located in the sunlit hemisphere of the Earth. In this paper, by using the solar radio flux data, L-band scintillation data, and GPS receiver observation network data located in different regions, effect of the 13 December 2006 solar radio burst on GPS observations are investigated in detail. Results show that the disruption caused by this radio burst event is obvious, and the amplitude scintillation events occur and GPS signal losses of lock are detected. Furthermore, the GPS satellite signal locked at several GPS station is interrupted and the observed GPS satellite number is less than 4 during this solar radio burst. The event resulted in GPS service failure for about six minutes. By comparison, those stations located nearby sub-solar point are more serious than that of far away from it.

  • 辐射带高能电子通量波动与地磁暴警报

    Subjects: Geosciences >> Space Physics submitted time 2016-05-13

    Abstract: The outer radiation belt consists mainly of high energy electrons trapped by the Earth's magnetic field. The disturbance of the geomagnetic field caused by the Coronal Mass Ejection (CME) or the Co-rotating Interaction Region (CIR) can result in electron radiation belt variations. According to the variation feature of high energy electron flux in the outer radiation belt during magnetic storms, a novel index referred to as high electron flux fluctuation index was evaluated by using the 5-min resolution sampled electron flux data provided by GOES, and its correlation with geomagnetic Kp index was analyzed. It is found that high electron flux fluctuation index has a good correlation with geomagnetic Kp index, and the new index can be used as an indicator of geomagnetic storm occurrence. In comparison with 3-hour Kp index, which is wildly used in space environment operation prediction system, the suggested index in this paper can alert geomagnetic storm occurrence earlier.

  • 2006年12月13日太阳射电暴对GPS观测的影响

    Subjects: Geosciences >> Space Physics submitted time 2016-05-13

    Abstract: Solar activity and Earth's space environment can effect the operation and safety of spacecraft, and they are also the main error source of navigation, positioning, and communication based on radio waves applications system. In this field, the L-band solar radio burst is regarded as a potential threat to Global Navigation Satellite System(GNSS) stability and performance. When the solar radio burst exceeds a threshold value, the radio noise from solar emission will increase dramatically, which can give rise to GNSS receiver tracking loss and positioning failure located in the sunlit hemisphere of the Earth. In this paper, by using the solar radio flux data, L-band scintillation data, and GPS receiver observation network data located in different regions, effect of the 13 December 2006 solar radio burst on GPS observations are investigated in detail. Results show that the disruption caused by this radio burst event is obvious, and the amplitude scintillation events occur and GPS signal losses of lock are detected. Furthermore, the GPS satellite signal locked at several GPS station is interrupted and the observed GPS satellite number is less than 4 during this solar radio burst. The event resulted in GPS service failure for about six minutes. By comparison, those stations located nearby sub-solar point are more serious than that of far away from it.