If the signal is spread-spectrum (frequency hopping every few milliseconds) according to a preset sequence of frequencies coordinated between the operator and the drone, the signal could be real-time and virtually unbreakable without the key to the pattern, which could be randomly generated at launch and shared between operator and drone by an encrypted signal.
You wouldn't want the operator on another continent, as the satellite delay would be too long.
Thank you. So how close do you have to be?