Performance evaluation of different troposphere delay models and mapping functions

Tropospheric delay is a major error source in positioning by Global Navigation Satellite Systems (GNSSs). System users often apply one of the available troposphere models without giving sufficient background on their performance. In this study, the performance of different known hydrostatic and wet troposphere delay models and mapping functions are internally and externally compared and analysed at selected sites around the globe. International GNSS Service (IGS) products were used as a reference. The best performing models are presented. Results showed that small discrepancies are present between different models. All models perform significantly better at the mid-latitudes than at the Equator.

► Various troposphere delay models and mapping functions were compared and analysed.
► All hydrostatic models perform better at the mid-latitudes than at the Equator.
► The wet models had poor performance and their use in practice is not recommended.
► The Vienna mapping functions are regarded as the best for geodetic purposes.
► The differences among mapping functions are large at the Equator.