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by ars 1597 days ago
See: https://en.m.wikipedia.org/wiki/Spread_spectrum along with cryptographically randomized frequency hopping, you would not be able to figure out when there is an actual signal rather than noise.
1 comments

Picture a point source frequency hopping different collars of visible light on your wall. There are real limits to how many photons it can send before it becomes really obvious.

As satellites need to detect returns bounced off the ground hundreds of miles away they have some hard minimums for high resolution images vs aircraft or ground stations. 10x distance needs 100x the signal.