Alphabet’s (Google’s) Wing division recently [criticized the FCC’s new drone,](https://wing.com/resource-hub/articles/remote-id-rule/) claiming the radio ID broadcast would be an invasion of privacy. As I understand it, they are saying that a listening device can track the location and route of all drones within its range. It would be similar to someone being able to wirelessly track the location of all car’s within range of an antennae.
This made me think about the radio most of us have in our pockets, which broadcasts to nearby cell towers. Can this be wirelessly tracked as easily as that drone RID? I know the contents of messages/data/voice between a cellphone and tower are encrypted. But, do cellphone broadcasts still contain some sort of unencrypted signature? Maybe it’s the IMEI, or something else a person could use to fingerprint a cellphone.
If cellphone broadcasts do contain a somewhat-unique signature, then multiple listening antennas would be able to triangulate/track the locations of cellphones within a range. If cells don’t have a signature, then the margins for error on triangulation accuracy would grant us some anonymity. You could still plot the locations of all cell signals within range, but anytime one path collides with another it would be difficult to accurately deduce which of the two+ converging cellphones took which direction. Particularly within crowding buildings.
I apologize if this question violates rule #3, or some other rule I’m not aware of. It didn’t seem “basic” to me, but you never know. Also, I know about cell-site simulators like Stringrays. But those aren’t passive antennas like what I’m describing above.