These can be used for relaying the data from tiny helmet cams worn by the military.
These can be used to send/receive data from an IC on a circuit board in a device that has an SDR embedded.
The overall gain of these satellites is probably a bit greater than the gigantic Robert C. Byrd Green Bank Telescope .... they are of similar size, one points to space, the other points to YOU.
Given the almost inconceivable gain of these satellites with their enormous antennae it's as though every point on the earths surface is only an couple of feet away from a sophisticated receiver with a small whip antenna attached...seriously.
Just imagine what you could do with such a setup.
Take a cheap Chinese handi-talkie and program an odd frequency into it and start talking...it's almost certain that its being listened to by these sats and archived. The use of an odd frequency that is quiet is a red flag.
Only frequencies that are massively in use are safe from detection by these sats... i.e. the microwave oven assigned frequency of 2,450 MHz is just an enormous roar for these sats..too much noise to pick up a terrestrial link on the same freq. ditto freqs like the FRS channels...etc
The frequencies used by satellite TV providers are also a huge roar since every metal object on the ground is reflecting this RF back up to these sats... this would be a good choice for short range data use that needed to be secure.