Ionospheric indices give information about ionospheric perturbations, which may cause absorption, diffraction, refraction, and scattering of radio signals, including those from global navigation satellite systems (GNSS). Therefore, there may be a relationship between index values and GNSS positioning results. A thorough understanding of ionospheric indices and their relationship to positioning results can help monitor and forecast the reliability and accuracy of GNSS positioning and support the precision and safety of life applications. In this study, we present the relationship between three indices: Gradient Ionosphere indeX (GIX), Sudden Ionospheric Disturbance indeX (SIDX), and Rate of Total electron content Index (ROTI) in relation to precise positioning results. We used two approaches: precise point positioning (PPP) and relative positioning for long baselines. We focus on GNSS stations located in Europe for two selected geomagnetic storms: March 17, 2015, and May 22, 2015. Our results show that in the case of PPP, positioning degradation occurred mainly at high latitudes and was mostly caused by rapid small-scale changes in ionospheric electron content represented by SIDX and ROTI. We also showed a significant correlation between cycle slips of GNSS signals and ROTI (0.88). The most significant degradations for relative positioning for low and medium latitudes were associated with large spatial gradients reflected by the GIX.

电离层指数提供有关电离层扰动的信息，电离层扰动可能导致无线电信号的吸收、衍射、折射和散射，包括来自全球导航卫星系统 (GNSS) 的信号。因此，索引值和GNSS定位结果之间可能存在某种关系。深入了解电离层指数及其与定位结果的关系，有助于监测和预测GNSS定位的可靠性和准确性，为生活应用的精度和安全性提供支持。在本研究中，我们提出了梯度电离层指数（GIX）、突发电离层扰动指数（SIDX）和总电子含量指数（ROTI）三个指数与精确定位结果之间的关系。我们使用了两种方法：精确点定位（PPP）和长基线相对定位。我们重点关注位于欧洲的两次选定的地磁风暴：2015 年 3 月 17 日和 2015 年 5 月 22 日。我们的结果表明，在 PPP 的情况下，定位退化主要发生在高纬度地区，并且主要是由快速小磁暴引起的。以 SIDX 和 ROTI 表示的电离层电子含量的尺度变化。我们还发现 GNSS 信号的周跳与 ROTI 之间存在显着相关性 (0.88)。低纬度和中纬度相对定位最显着的退化与 GIX 反映的大空间梯度有关。