We're doing much more work now with RTK devices in our application and this was recently an issue for us.
A customer had been complaining that the RTK devices we were supporting were not working correctly and I got sent out there to have a look. After some back on forth and getting tests done on site, they revealed they often didn't get good fixes with any equipment between late morning and late afternoon, and that's how I found out about ionospheric interference and the the correction service's ionospheric warning page which consistently reported high interference around these times
The existing ground-station ionosphere data mentioned has been used to detect missile launches: https://www.armscontrolwonk.com/archive/1216884/detecting-mi...
I imagine you could do the same thing with much better coverage using this distributed ionosphere monitoring method.
Interesting use by Google of everyone's android phone data to compute space weather info.
Do users who unknowingly contributed sensor data get a sticker or badge or anything? Reminds me of seti@home.
What else could you do with full control of a global botnet of high powered sensor packs like android phones?
Imagine if they all transmitted simultaneously in a manner that was phase synchronized at a particular destination…
Most current day cellphone antennas don't have phasing for any tuned directionality. There are hard limits to array size due to physics and phones are just very small compared to yhe wavelengths they use.
And then there is the general challenge of synchronizing the transmitter phase. There is only so much that can be done via GNSS.
If cellphone frequencies were not filled with cellphones, it could make for a neat radiotelescope on receive.
What would you expect to happen?