Fade margin

Fade margin is like having extra cookies in case your friends come over to play.

When you use a cell phone or satellite to talk to someone far away, the signal travels through the air and can get weaker as it goes. Fade margin is kind of like extra strength in case the signal gets weaker than expected.

Just like how you might have extra cookies in case your friends eat more than you thought they would, fade margin gives extra signal strength in case the transmission signal gets weaker due to things like weather or obstacles.

It's important to have enough fade margin so that you don't lose your signal and can still talk to your friends.