Generation of synthetic atmospheric events for the evaluation of millimeter wave earth-space propagation impairments
(2025)
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- Abstract
- This thesis addresses the modeling and validation of rain attenuation in satellite communication systems, focusing on high-frequency bands and the integration of numerical weather prediction (NWP) data. With future systems moving above 20 GHz, accurate understanding of precipitation effects is essential. A framework is developed to model, simulate, and validate attenuation for both geostationary (GEO) and low Earth orbit (LEO) links, using measurements from the Alphasat ground station in Louvain-la-Neuve, Belgium. Gaseous, cloud, and rain attenuation are derived from the Weather Research and Forecasting (WRF) model. While gaseous effects are stable and approximated with cosecant laws, cloud and rain show strong spatial and temporal variability, requiring high-resolution 3D data. Three rain models are examined: (1) Mie scattering from rainwater content, (2) direct WRF rain rates, and (3) a hybrid MultiEXCELL–optical flow approach. The hybrid method best reproduces measured distributions, particularly in the critical 0.1–1% excess range. Validation against ITU-R models and experimental data shows good agreement for gases, underestimation for clouds, and improved accuracy for rain with synthetic refinement. Extraction of attenuation from Alphasat data enables robust model comparison. Finally, the framework is applied to LEO satellites, showing that while some passes avoid rain, reliable system design must consider rain-induced outages. In conclusion, integrating NWP data into attenuation modeling, especially with MultiEXCELL refinement, provides accurate, high-resolution simulations. The framework advances propagation modeling for both research and satellite system design.
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Citations
Razavian, S. M. (2025). Generation of synthetic atmospheric events for the evaluation of millimeter wave earth-space propagation impairments.