The Uplink Asymmetry
Why sending a signal up is a harder problem than beaming one down.
Transmit Power
Phone
0.2 W
Terrestrial tower
~40 W
A phone transmits roughly 1/200th the power of a ground base station.
Distance to Receiver
Terrestrial cell
~1-2 km
Satellite
~340-550 km
The satellite is roughly 300x farther than a typical ground cell.