巨烈磁暴对全球GNSS观测信号的影响

介绍了一种GNSS L₁和L₂信号及测距码失锁率统计计算方法，并考察了不同卫星高度角对失锁率计算结果的影响.利用全球GNSS观测数据，分析了第23太阳活动周发生的两次巨烈磁暴期间GNSS观测信号的质量.结果表明:巨烈磁暴发生期间GNSS L₁和L₂信号及P₁和P₂码失锁率较平静日均显著增加，信号失锁主要发生在磁暴主相及恢复相前期.L₂失锁率明显高于L₁且失锁持续时间更长，表明L₂比L₁更易受到磁暴影响.GNSS 信号失锁率与磁暴指数SYM-H的高相关性表明信号失锁率的异常增加由巨烈磁暴所驱动.研究成果可为我国北斗卫星导航系统全球信号质量评估提供方法支持.

Influence of Strong Geomagnetic Storms on Global GNSS Observation Signals

A method for calculating the rate of loss-of-lock(LOL)at carrier phase and pseudo-range measurements of GNSS L₁ and L₂ was introduced， and the impacts of different satellite elevation angles on the LOL rate were also investigated. Using global GNSS observations， the qualities of GNSS signals during two strong geomagnetic storms at the 23rd solar cycle were analyzed. The results showed that the LOL rates of L₁， L₂， P₁ and P₂ signals significantly increased during strong geomagnetic storms comparing with the quiet days. The LOL mainly occurred in the main phase and the early recovery phase of the storm. The LOL rate of L₂was significantly higher than L₁， and the LOL duration was longer. This means the L₂ was more sensitive to geomagnetic storm than L₁. The high correlation between the LOL rate and SYM-H index indicated that the abnormal increase of global LOL rate was driven by the strong geomagnetic storm. The results could provide methodological support for the assessment of signal quality of the Beidou navigation satellite system.