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I'm working on a project with multiple sensors. These sensors need to be synchronised with eachother as precisely as possible without a physical connection. I need to make sure that if I tell them to start measuring that they start at the same point. If one starts 1 microsecond later than the other then all the measurements will be no use.

Im planning on using GPS to make synchronise the clock rates as being demonstrated here https://pdfs.semanticscholar.org/0529/00a69bbb3db6a615bfb14843a5bcf54292d5.pdf So my GPS synchronises the relative time of the sensors, but can I also use it to synchronise the absolute time? so I can set a t(0) at the exact same time?

Autistic
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steven groot
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    Just make sure you do it right, otherwise you start measuring neutrinos that are faster than light... – PlasmaHH Feb 01 '17 at 11:12

1 Answers1

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Yes, GPS is used for exactly that purpose pretty often.

GPS receivers often emit a sharp pulse-per-second signal. Together with the current GPS or UTC time that you can query through the usual means (serial port NMEA messages), that allows for a synchronized understanding of absolute time.

For example, the Ettus USRPs (SDR devices) of all but the tiniest series can be equipped with a GPSDO, which then can be used for exactly that: Synchronizing not only sampling rate and LO frequencies, but also absolute time across multiple transceivers.

Marcus Müller
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