About The Impact Of Nwp Models' Temporal Resolution On Rain Attenuation Forecasts

The ever increasing demand for more data transmission capacities also includes the field of satellite communications. Satellite links with higher frequencies provide large bandwidths, but are more prone to degradation by atmospheric phenomena on the earth - space path. Reliable short term forecasts of weather and channel characteristics will ease appropriate mitigation, like employment of diversity techniques or adaptive code modulation. Numerical weather prediction (NWP) models area available on global scale as a potential basis for such forecasts. Rain is the strongest effect, with the rain rate being highly variable in time. This study discusses, what rain rate integration time and thus NWP forecast step width is suitable for forecasting satellite channel characteristics. The link attenuation is calculated on basis of disdrometer measurements for various integration times and the resulting fade slope statistics compared against the expectation by the ITU-R P.1623 model [1]. It is shown, that NWP models with forecast steps of 5 minutes or less are interesting for such purpose.