I'm wondering how this would work in practice. Does anyone know what kind of receiver/transmitter would be needed to communicate with a drone 20km or more away

I'm wondering how this would work in practice. Does anyone know what kind of receiver/transmitter would be needed to communicate with a drone 20km or more away? Is it feasible, in terms of device size and power consumption, to embed such a radio in a like a laptop? How about a smartphone? Or is the idea that the drone would communicate with base stations that would use conventional wireless signalling to talk to user devices? And if so, how does using a drone improve upon the current approach linking base stations using microwave links? Thoughts, anyone?