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使用数以百万计的手机绘制电离层地图
Jamie Smith1, Anton Kast1, Anton Geraschenko1
1Google Research, Mountain View, CA, USA.
Nature
|November 13, 2024
概括
数以百万计的安卓手机现在可以监测地球的电离层,填补数据缺口,提高全球卫星导航系统 (GNSS) 的准确性. 这种智能手机网络提供了更清晰的太空天气对定位的影响.
科学领域:
- 地质物理学和空间物理学
- 大气科学
- 血物理
背景情况:
- 电离层是电离等离子 (50-1500公里高度) 的区域,显著影响全球卫星导航系统 (GNSS) 的信号.
- 电离层总电子含量 (TEC) 的变化是定位,导航和计时 (PNT) 服务的主要错误来源.
- 现有的地面GNSS网络存在时空数据缺口,限制了电离层TEC地图的准确性.
研究的目的:
- 调查使用智能手机分布式网络作为电离层监测的新工具的可行性.
- 评估智能手机数据的潜力,以填补传统的电离层观测网络的空白.
- 通过智能手机数据获得的强化离子层模型来证明位置精度的提高.
主要方法:
- 使用安卓智能手机上数以百万计的噪音传感器收集电离层TEC数据.
- 开发了处理和整合智能手机数据到现有的电离层测绘技术的方法.
- 将智能手机增强的离子层地图的覆盖范围和准确性与传统方法进行了比较.
主要成果:
- 智能手机数据成功地使测量覆盖率翻了一番,填补了电离层观测中的关键时空差距.
- 解决了关键的电离层现象,包括等离子体泡 (印度,南美),太阳风暴增强密度 (北美) 和中度低谷 (欧洲).
- 通过智能手机数据改进的电离层地图提高了GNSS的位置准确性.
结论:
- 一个大规模的智能手机网络可以作为一种强大而低成本的科学仪器来监测电离层.
- 基于智能手机的离子层监测显著提高了PNT服务的准确性和覆盖率,特别是在数据稀缺的地区.
- 这种方法突显了利用无处不在的移动技术来实现基础地球科学研究和应用的潜力.
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