Modelling tropospheric effects in space and time for the design of advance Earth-space links operating in the EHF range
The aim of the doctoral thesis is to develop a space-time model of the atmospheric constituents affecting Earth-space links (i.e. rain, clouds and gases) operating in the EHF range. Such a model will allow simulating the interaction between EM waves and Earth-space links to derive accurate statistical predictions of detrimental tropospheric effects, to be compared with those observed during radiowave propagation experiments. The idea is to extend a well-known space-time rain model, namely ST-MultiEXCELL, to include cloud fields (whose effect can no longer be neglected as the operational frequency of satellite links increases beyond 30 GHz) and water vapor fields (whose impact is more limited but always present). Numerical weather products, such as ERA5 from ECMWF provided over a regular latitude/longitude grid and embedding geographical and seasonal variations, will be used as input to the model. Satellite observations, like the ones provided by EUMETSAT (in particular the MSG satellites for cloud observation), will be used to develop the evolution of clouds and rain, simultaneously, in time and space. Measurements performed during propagation campaigns (e.g. rain rate and path attenuation) will be used to validate the model, which will mainly provide as output timeseries of the attenuation affecting the Earth-space links. The model is to be designed in a way that it is applicable to a multitude of scenarios such as LEO/MEO/GEO satellite links operating at frequencies ranging from the Ka band to the W band, and even beyond. Such a model will support the investigation and design of fade mitigation techniques (e.g. site diversity, uplink power control), to be applied to overcome the extremely high attenuation values experienced along Earth-space links under adverse weather conditions.
Back to Current Students