Investigating Ionospheric Scintillation Effects on Multifrequency GPS Signals
Investigating Ionospheric Scintillation Effects on Multifrequency GPS Signals
复制标题
研究电离层闪烁对多频 GPS 信号的影响
DOI：
10.1007/s10712-021-09643-7
复制
发表时间：
2021
影响因子：
4.6
通讯作者：
E. D. de Paula
中科院分区：
文献类型：
--
作者：
L. A. Salles;B. Vani;A. Moraes;E. Costa;E. D. de Paula
在过去的15年里，随着L2 C和L5信号的引入，全球定位系统的卫星星座已经现代化，以实现更精确的应用。然而，除其他影响外，它们容易受到严重的电离层影响，特别是在赤道和低纬度地区。赤道等离子体泡是电离层电动力学、等离子体不稳定性机制和热层耦合共同作用的结果，它可以产生尺度从几百公里到几米（或更小）不等的不规则结构。电离层的不规则性可能会引起跨电离层信号的深度幅度衰落和相移。也就是说，它们是幅度和相位闪烁的原因，这会降低接收机的工作性能，并可能在极端条件下导致定位和导航服务故障和不可用。本工作的目的是分析电离层闪烁对L2 C和L5 GPS信号的影响，比较它们与L1信号的脆弱性。本分析中使用的数据是在2014年11月至2015年3月期间收集的，在第24周期的最大太阳活动期间（闪烁发生率很高的时期），由部署在巴西领土上四个不同地点的闪烁监测器收集：福塔莱萨，Presidente Prudente，São José dos Campos和波尔图阿莱格雷。强度衰落将进行分析，考虑不同的阈值，揭示他们的经验概率分布的闪烁发生，平均衰落发生和持续时间。结果将表明，在现代化信号中出现强闪烁的概率更大，与传统L1信号中的事件相比，L5信号中的事件高达五倍。它将被证明，L5平均衰落持续时间明显长于相应的其他频率，考虑到相同的网站，阈值，和L1幅度闪烁水平。结果还将表明，考虑到相同的幅度闪烁水平和位置，在− 6至− 15 dB的阈值范围内，平均衰落持续时间根据平均比率0.6 s/3 dB减小。
Over the last 15 years, the satellite constellation of the global positioning system (GPS) has been modernized for more precise applications, with the introduction of the L2C and L5 signals. However, among other effects, they are susceptible to severe ionospheric effects, particularly in the equatorial and low-latitude regions. Equatorial plasma bubbles, resulting from the combination of the ionospheric electrodynamics with plasma instability mechanisms and thermospheric coupling, may generate irregularity structures with scale sizes ranging from hundreds of kilometers to a few meters (or less). Ionospheric irregularities may cause deep amplitude fades and phase shifts to transionospheric signals. That is, they are responsible for amplitude and phase scintillation, which degrade receiver operations and may cause failures and unavailability to positioning and navigation services under extreme conditions. The objective of the present work is to analyze ionospheric scintillation effects on the L2C and L5 GPS signals, to compare their vulnerabilities with those of the L1 signal. The data used in this analysis were collected between November 2014 and March 2015, during the maximum solar activity of cycle 24 (a period of great scintillation incidence), by scintillation monitors deployed at four different sites in the Brazilian territory: Fortaleza, Presidente Prudente, São José dos Campos, and Porto Alegre. Intensity fades will be analyzed, considering different thresholds, to reveal their empirical probability distributions of scintillation occurrence, average fading occurrences and durations. The results will show that greater probabilities of strong scintillation occurrences are present in the modernized signals, reaching up to five times more events in the L5 signal in comparison with those in the legacy L1 signal. It will be shown that the L5 average fade duration is distinctly longer than the corresponding ones for the other frequencies, considering the same site, threshold, and L1 amplitude scintillation level. The results will also show that the average fade duration decreases according to the average ratio 0.6 s/3 dB within the threshold range from − 6 to − 15 dB, considering the same amplitude scintillation level and location.
DOI：
10.1002/navi.379
发表时间：
2020-08
期刊：
NAVIGATION
影响因子：
--
作者：
J. Vilà‐Valls;N. Linty;P. Closas;F. Dovis;J. Curran
通讯作者：
J. Vilà‐Valls;N. Linty;P. Closas;F. Dovis;J. Curran