In this letter, we study the temporal and spatial variability of ionospheric irregularities by generating high-resolution maps of the observed amplitude scintillation index (S4) using data from a multiconstellation and multifrequency global navigation satellite system (GNSS) receiver. The study is located in the Arabian Peninsula region, which falls under the northern crest of the equatorial ionization anomaly (EIA). Even though the study was conducted during a solar minimum period, considerable pre-sunset scintillation occurrences have been observed between 15 and 17 local time (LT), particularly during the winter solstices. While most scintillation occurrences have been observed at low elevation (20°–25°), a considerable number of scintillation causing ionospheric irregularities have been observed toward the north, east, and southeast of the receiver location, for elevation ranging from 40° to 60°. Out of all the GNSS constellations with medium-earth-orbit (MEO) satellites, GPS was the most impacted by amplitude scintillation, while BeiDou and Galileo satellites were the least affected. It is anticipated that the patches of ionospheric irregularities reported in this work will be further enhanced, as solar activity increases in the coming years. Therefore, this work can serve as a reference for future studies during periods of increased geomagnetic activity.

中文翻译：

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太阳极小期期间阿拉伯半岛上空 S4 的测绘

在这封信中，我们通过使用来自多星座和多频全球导航卫星系统 (GNSS) 接收器的数据生成观测幅度闪烁指数 (S4) 的高分辨率地图来研究电离层不规则性的时空变化。该研究位于阿拉伯半岛地区，该地区位于赤道电离异常 (EIA) 的北峰之下。尽管该研究是在太阳活动极小期进行的，但在当地时间 (LT) 15 至 17 日之间观察到大量的日落前闪烁事件，尤其是在冬至期间。虽然在低海拔（20°–25°）观察到大多数闪烁现象，但在北部、东部、和接收器位置的东南方，仰角范围为 40° 至 60°。在所有具有中地球轨道 (MEO) 卫星的 GNSS 星座中，GPS 受振幅闪烁的影响最大，而北斗和伽利略卫星的影响最小。预计随着未来几年太阳活动的增加，这项工作中报告的电离层不规则斑块将进一步增强。因此，这项工作可以为未来地磁活动增加期间的研究提供参考。预计随着未来几年太阳活动的增加，这项工作中报告的电离层不规则斑块将进一步增强。因此，这项工作可以为未来地磁活动增加期间的研究提供参考。预计随着未来几年太阳活动的增加，这项工作中报告的电离层不规则斑块将进一步增强。因此，这项工作可以为未来地磁活动增加期间的研究提供参考。