Fade Margin

A Fade Margin needs to be applied to the link budget to take into account changes in the radio path caused by changes in objects surrounding or in the path, for example moving objects such as traffic or the changes in foliage brought on by seasonal change. The Fade Margin for NLoS links used in the calculation is a function of excess path loss, and is taken from the following graph:

_images/fade_margin.jpg

Fade Margin vs Excess Path Loss for 99.99% Link Availability

The Fade Margin for LoS links is a function of location, path length, antenna heights, and spatial diversity, and it is computed using ITU-R P.530-12 or ITU-R P.530-17. The estimation tool adds together the probabilities for the NLoS fading and the LoS fading.