A new precision improvement in zenith tropospheric delay estimation by GPS

摘要: Accurate GPS-derived ZTD (zenith tropospheric delay) plays a key role in near real-time weather forecasting, especially improving the precision of Numerical Weather Prediction (NWP) models. However, is usually estimated under assumption that all GPS measurements, carrier phases or pseudo-ranges, have same accuracy. These assumptions are unrealistic, which will inevitably degrade estimation. This communication aims to further improve estimation by stochastic modelling. The results show can be obviously improved using suitable model for measurements. satellite elevation angle-based cosine function better than other investigated improvement certainly critical reliable NWP and delay corrections.