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Measurement of the Directional Information Flow in fNIRS-Hyperscanning Data using the Partial Wavelet Transform Coherence Method
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Analysis of Spatial Decorrelation of Small-Scale Tropospheric Delay Using High-Resolution NWP Data.
Jan Erik Håkegård1, Nadezda Sokolova1, Aiden Morrison1
1SINTEF Digital, Strindveien 4, 7032 Trondheim, Norway.
Sensors (Basel, Switzerland)
|February 11, 2023
Summary
This study estimates differential zenith tropospheric delay (dZTD) using high-resolution numerical weather product data for Northern Europe. Results show dZTD up to 18 cm, crucial for understanding impacts on Global Navigation Satellite Systems (GNSS).
Area of Science:
- Geodesy and Geophysics
- Atmospheric Science
- Satellite Navigation
Background:
- Tropospheric delay significantly impacts precise satellite navigation.
- Accurate estimation of differential zenith tropospheric delay (dZTD) is essential for mitigating these errors.
- Numerical Weather Product (NWP) data offer a high-resolution alternative for dZTD estimation.
Purpose of the Study:
- To estimate dZTD over Scandinavia, Finland, and the Baltic countries using NWP data.
- To analyze the spatial and temporal characteristics of dZTD for short baselines (up to 20 km).
- To provide a foundation for investigating the impact of dZTD on GNSS integrity in the region.
Main Methods:
- Utilized high-resolution (2.5x2.5 km) NWP data from MET Norway.
- Calculated dZTD for grid positions to derive tropospheric gradients.
- Processed one year of data to identify dZTD magnitudes and event locations.
Main Results:
- Estimated dZTD values up to 18 cm for baselines up to 20 km.
- Identified geographical areas with the largest dZTD events within the study region.
- Preliminary comparison between NWP-based and GNSS-based dZTD results was performed.
Conclusions:
- NWP data provide valuable insights into dZTD characteristics for short baselines.
- The findings highlight the potential variability of tropospheric delay in the studied region.
- This research is a precursor to assessing dZTD's impact on GNSS-based navigation systems.
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