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Re:The new warrant: how US police mine Google for your locat... by eurasiantiger on Thursday September 16, 2021 @05:18PM (#28557766)
These newfangled beamforming systems can alter the direction of transmission to optimize signal quality for your phone. How can they do that if the system cannot locate a handset with great accuracy?
Re:The new warrant: how US police mine Google for your locat... by PeterisP on Friday September 17, 2021 @12:45PM (#28567659)
I have no idea about what information the (5G?) beamforming protocols use; perhaps they have figured out a way for some "angle discovery" as part of the protocol handshake or perhaps they just require the device send GPS data for that adjustment (and in the absence of that data would just skip beamforming, getting worse rates); but the distance information for the 4G/LTE timing system would be an inherent part of the protocol even if the device does not have GPS enabled and is based on literally measuring the round-trip timing.
Re:The new warrant: how US police mine Google for your locat... by eurasiantiger on Friday September 17, 2021 @05:22PM (#28571059)
From Wikipedia/MIMO:

”To correctly form a beam, the transmitter needs to understand the characteristics of the channel. This process is called channel sounding or channel estimation. A known signal is sent to the mobile device that enables it to build a picture of the channel environment. The mobile device sends back the channel characteristics to the transmitter. The transmitter can then apply the correct phase and amplitude adjustments to form a beam directed at the mobile device. This is called a closed-loop MIMO system.”

Re:The new warrant: how US police mine Google for your locat... by iamstupidsimple on Thursday September 16, 2021 @06:48PM (#28558790)
Beams don't have to be that accurate to boost signal quality.

This is also speculation on my part but I'd suspect they're targeting specific clusters of devices in an area and using multiplexing than having dozens of radios on one tower.