As far as I'm aware they just timestamp the sample streams based on a local gps ...

		jasonwatkinspdx 14 days ago \| parent \| context \| favorite \| on: NIST was 5 μs off UTC after last week's power cut As far as I'm aware they just timestamp the sample streams based on a local gps backed atomic reference. Then when they get the data/tapes in one computing center they can just run a more sophisticated correlation entirely in software to smooth things out.