ROTI计算策略的初步分析比较

发布时间：2018-07-20 17:10

【摘要】：由电离层闪烁和TEC(Total Electron Content)监测仪获取的振幅闪烁指数S4和相位闪烁指数σ?是电离层闪烁研究中最常用的参数,由双频GNSS(Global Navigation Satellite System)接收机获取的电离层TEC变化率指数ROTI(Rate of TEC Index)与S4指数的相关性已得到很多相关研究的验证,ROTI也是电离层闪烁研究的一个有效参数,这样就使利用全球分布的大量GNSS观测数据开展电离层闪烁研究成为可能.但是在不同的研究中计算ROTI所使用数据的采样率和计算间隔有所差异,对于计算策略的选择尚无定论.利用海南三亚1 s、15 s和30 s采样率的GNSS双频观测数据与电离层闪烁和TEC监测仪获取的S4指数,分析了在电离层闪烁发生时,不同计算策略获取的各类ROTI与S4指数的相关性,分析比对了几类ROTI对电离层闪烁的敏感性.分析结果表明:各类ROTI与S4指数都具有较强的相关性,在大多数情况下,不同种类ROTI都可以在闪烁发生期间响应S4指数的变化;不同采样率的ROTI在响应S4指数变化时,判断是否发生电离层闪烁事件的阈值有所差异;由于ROTI和S4指数监测电离层闪烁的机理不同,也会出现几个参数不能同时反映电离层受扰动的情况,在进行电离层闪烁监测、预报和预警时,建议同时采用多个参数综合分析;在同等的电离层条件下,15 s和30 s采样率的ROTI在数值上比较接近,但是两者明显小于1 s采样率的ROTI.使用GNSS接收机进行电离层闪烁观测时,建议采用高于1 s采样率的GNSS观测数据.
[Abstract]:Amplitude scintillation index S4 and phase scintillation exponent 蟽? Is the most commonly used parameter in ionospheric scintillation, The correlation between the ionospheric TEC variability index (Rate of TEC Index) and the S4 index obtained from the dual-frequency GNSS (Global Navigation Satellite system) receiver has been verified by many relevant studies that ROTI is also an effective parameter in ionospheric scintillation. This makes it possible to study ionospheric scintillation using a large number of globally distributed GNSS observations. However, the sampling rate and the calculation interval of the data used to calculate ROTI are different in different studies, and the choice of calculation strategy is not conclusive. Using the GNSS dual-frequency data of 15 s and 30 s sampling rate in Sanya, Hainan, and the S4 index obtained by ionospheric scintillation and TEC monitor, the correlation between various ROTI and S4 index obtained by different calculation strategies during the occurrence of ionospheric scintillation is analyzed. The sensitivity of several classes of ROTI to ionospheric scintillation was analyzed and compared. The results show that all kinds of ROTI have strong correlation with S4 exponent. In most cases, different types of ROTI can respond to the change of S4 exponent during the occurrence of scintillation, and the ROTI with different sampling rate can respond to the change of S4 exponent. The threshold of ionospheric scintillation event is different. Because of the different mechanism of monitoring ionospheric scintillation by ROTI and S4 index, several parameters can not reflect the ionospheric disturbance at the same time, so the ionospheric scintillation monitoring is carried out. In forecasting and early warning, it is suggested that multiple parameters should be used for comprehensive analysis at the same time. Under the same ionospheric condition, the ROTI of 15 s and 30 s sampling rates is relatively close, but both are obviously less than the ROTI of 1 s sampling rate. For ionospheric scintillation observations using GNSS receivers, GNSS observations with a sampling rate above 1 s are recommended.
【作者单位】：中国科学院上海天文台;中国科学院大学;
【基金】：国家重点研发计划(2016YFB0501503-3) 国家自然科学基金项目(41730108)资助
【分类号】：P228.4

【相似文献】