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by hereforphone 1085 days ago
It doesn't quite work like that.
3 comments

Explain. Why not?

The site advertises the ability to track individual handheld VHF/UHF radios, which are within an order of magnitude of the transmit power of cellular handsets. Even if they don't have the power to do that right now, they certainly could in the next generation of satellites.

Or they might already have the power right now and just not be advertising it. Or maybe the hardware is there but the software is still being refined. (This strikes me as the most likely, since the digital transmission from a cellphone is significantly different from analog voice, it would take some different processing layers to handle it.)

With the current constellation, they advertise 24 passes per day, but as they continue to add satellites, it approaches continuous. Furthermore, if the capability is commercially valuable, it's possible that other megaconstellations could just add the functionality to their own next-gen birds and then it's completely game-over.

The limiting factor, as I understand it, would be downlink bandwidth. And there are a number of mitigations (on-orbit processing and compression, etc) for that.

Do you mean a phone wouldn't broadcast an IMSI, without a base station nearby?

It sounds like passive IMSI catching is possible though - https://harrisonsand.com/posts/imsi-catcher/ at least when a phone connects to a base station.

That entirely depends on the sensitivity of their detection; but I'd guess that it does work like that.