Hey folks,

I've bought a TinySA a while ago for some other project, but something
has cropped up that? makes me wonder if it can help here. I'm not an RF
professional, I know enough to know I don't know anything.

A good friend is going through a breakup, and there's credible evedince
their evicted ex has been spying on them. We did find a hidden
smartphone running a baby monitor app already. Wifi/Network are changed,
so any devices relying on that (e.g. ESP32-equipped power bars) are
eliminated.

However we have reason to suspect there's a cellphone hidden in or the
vicinity of the bedroom. My current approach is to inspect the power
outlets one by one to see if a power supply has been connected and the
setup stowed away behind some paneling.

I wonder if there's a way to use the TinySA to home in on such a device
as well. I've done some limited resarch into it, and found e.g. videos
of people using a HackRF to decode some cellular traffic between the
base station and their smartphone. These were quite sophisticated,
seemed to rely both on a lot of protocol knowledge (I don't have) and
even prior information from the smartphone itself about used
channels/modulations, that for obvious reasons also are unknown. I don't
even know which kind of technology is being used. 3G, 4G are most
likely, but these to my knowledge are umbrella-terms that cover a broad
range of frequencies and modulations and other protocol details. So I'm
just overwhelmed where to start.

If somebody has some idea if the TinySA can be used to at least detect
the presence if not precise location of a cell phone so we can be sure
that we have to rip half the room apart, that would be splendid. I know
it's a moonshot and if it is just not working that way, then I'll accept
that as well.

Thanks for your consideration, and I'll be back in the future with my
actual purpose I bought the little bugger for.

Cheers,

Diez