3 ms·

> Distance Don’t modern cell towers use beamforming? In which case they get direction as well as RTT, so triangulation is not even needed (although it makes lo

• PeterisP 7y ago
  I may be wrong, but I think that at least the vast majority current widely depoyed systems don't use beamforming, it seems more of a "here's a tech demo that we're going to roll out soon with 5G" thing. However, it's a bit the opposite way around - it's not that they can use beamforming to get direction, but it's that they need to know the location before they can use beamforming - so the protocol (5g?) needs to require the device to know or obtain its location, and send it to the cell tower so that it can apply beamforming; similar to how in 3g the protocol includes measurements and adjustments of the timing advance so that the distance can be used when actually transmitting data. So it would be essentially like "the phone can't turn off GPS or transmitting it to everyone, because it needs it for the radio to work".