Using TV ATCS 3.0 Signals for GPS Backup in the USA

thebroadcastbridge.com

3 pointsthrow0101b2 comments

Cellular triangulation and Wi-Fi hotspot ID are two separate location systems that work when GPS is not available. Almost everyone has a cell phone in the US (95%).

Time is just as important as location for many use-cases:

> Machines called synchro-phasors are used to manage and regulate energy being added to the overall grid from all sources, including conventional power plants, wind farms, and solar panel arrays. It is critical to add new energy in a way that assures it is compatible with the existing energy flow. The synchro-phasor ensures the new power is added within one degree of top dead center of the 60 Hz energy carrier. For new energy to be successfully integrated, all synchro phasors need to be time correlated with each other within 1.0 µsec and correlated to UTC.

> This critical level of control requires all ATSC 3.0 clocks to be correlated to UTC. Overall, 200 ns accuracy satisfies requirements for all CI industries, if traceable to UTC.

And may cell systems get their time from GPS, and if they don't have local high-precision clocks they could start drifting from UTC.

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