Rain and Cloud Attenuation

Practical example:

To improve prediction of rain and cloud effects on systems in frequency bands up to at least 55 GHz

new satellite systems in 19/29 GHz band
stratospheric platforms (47 GHz)
high density terrestrial fixed links (> 30 GHz)
low availability VSAT systems (11/14 GHz)

Previous slide Next slide Back to first slide View graphic version

Notes:

Expressed example as a general need – to improve methods for predicting the effects of rain and cloud in the light of today’s systems – some of which listed in slide.

Common aspect is the high frequencies involved; Ka band increasingly used; HAPS at 47 GHz; increasing number of terrestrial microwave links used as backbone to FWA systems.

At these frequencies, rain effects are serious and correct allowance must be made for them in link budgets.

Fourth example refers to low availability VSAT system where, for reasons explained earlier, cloud will be the dominant mechanism.