Traditionally, GNSS space-based and ground-based estimates of tropospheric conditions are performed separately. It leads to limitations in the horizontal (e.g., a single space-based radio occultation profile covers a 300 km slice of the troposphere) and vertical resolution (e.g., ground-based estimates of troposphere conditions have spacing equal to stations’ distribution) of the tropospheric products. The first stage to achieve an integrated model is to create an effective 3D ray-tracing algorithm for the satellite-to-satellite (radio occultation) path reconstruction. We verify the consistency of the simulated data with the RO observations from the Constellation Observing System for Meteorology, Ionosphere, and Climate (COSMIC-1) Data Analysis and Archive Center (CDAAC) in terms of excess phase and bending angle. The results show that our solution provides an effective RO excess phase, with a relative error varying from 35% at the height of 25–30 km (1.0–1.5 m) to 0.5% at heights 5–10 km (0.1–1 m) and 14 to 2% at heights below 5 km (2–14 m). The bending angle retrieval on simulated data attained for high-resolution ray-tracing, bias lower than 2% with respect to the observed bending angle. The optimal solution takes about 1 s for one transmitter–receiver pair with a tangent point below 5 km altitude. The high-resolution processing solution takes 3 times longer.

传统上，全球导航卫星系统对对流层状况的天基和地面估计是分开进行的。它导致水平分辨率（例如，单个天基无线电掩星剖面覆盖对流层 300 公里的切片）和垂直分辨率（例如，对流层条件的地面估计的间距等于站点分布）的限制。对流层产品。实现集成模型的第一阶段是为卫星到卫星（无线电掩星）路径重建创建有效的 3D 射线追踪算法。我们验证了模拟数据与气象、电离层和气候星座观测系统（COSMIC-1）数据分析和档案中心（CDAAC）的RO观测在多余相位和弯曲角度方面的一致性。结果表明，我们的解决方案提供了有效的 RO 过剩相，相对误差范围为 25-30 km (1.0-1.5 m) 高度处的 35% 到 5-10 km (0.1-1 m) 高度处的 0.5%高度低于 5 公里（2-14 米）时为 14 至 2%。通过高分辨率光线追踪获得的模拟数据的弯曲角度检索，相对于观察到的弯曲角度的偏差低于 2%。对于切点低于 5 公里高度的一对发射器-接收器，最佳解决方案大约需要 1 秒。高分辨率处理解决方案的时间延长了 3 倍。