Commercial (Comm) Radio Occultation (RO) Raw Data Record (RDR) from Spire

This dataset contains Commercial (Comm) Radio Occultation (RO) raw data from Spire, which is an established method for remote sounding of the atmosphere. The technique uses an instrument in low-Earth orbit (LEO) to track radio signals from Global Navigation Satellite System (GNSS) transmitters as they rise or set through the atmosphere. The occulting atmosphere refracts or bends the radio signals, and given the precise positions of both satellites, the bending angle can be deduced from the time delay of the signal. Collecting these measurements for a full occultation through the atmosphere provides a vertical profile of bending angles, from which profiles of physical quantities such as temperature, humidity, and ionospheric electron density can be retrieved. These data primarily feed numerical weather prediction (NWP) models that support weather forecasts, and also support space weather analysis/prediction at NOAA.

本数据集包含来自Spire的商用无线电掩星（Commercial Radio Occultation, RO）原始数据，无线电掩星是一种成熟的大气遥感探测方法。该技术依托搭载于低地球轨道（Low-Earth orbit, LEO）的探测仪器，跟踪全球导航卫星系统（Global Navigation Satellite System, GNSS）发射机辐射的无线电信号——当信号穿过大气层升起或降落时，掩星路径上的大气会对无线电信号产生折射或弯曲效应。结合两颗卫星的精确轨道位置，可通过信号的时间延迟推算出信号弯曲角。对完整的大气掩星事件开展多组测量后，可获得弯曲角的垂直廓线，进而反演得到温度、湿度、电离层电子密度等物理参量的垂直廓线。此类数据主要为支撑天气预报的数值天气预报（Numerical Weather Prediction, NWP）模型提供核心输入，同时也可用于美国国家海洋和大气管理局（National Oceanic and Atmospheric Administration, NOAA）的空间天气分析与预报工作。