by MiracleRabbit
1 subcomments
- With GNSS+PPS and a hardware timer latch you can easily sync internal microcontroller timers to 2 to 3-digits nanoseconds against the global standard with a tightly controlled loop. But cannot get better than the PPS signal itself (roughly 30-100nS).
Everything below needs that a huge amount of engineering. CERN&friends developed the "White Rabbit" (https://ohwr.org/projects/white-rabbit/) system for this. This allows sub-Nanoseconds syncing of netwoked devices.
by ectospheno
1 subcomments
- That is cool. I use a gps NTP server on my home network and live with sub-millisecond time sync. I’d go PTP but the equipment is a bit too expensive if the only value add is better time sync and I don’t need additional bandwidth. Prices coming down would be nice.
by NkVczPkybiXICG
2 subcomments
- Why does the title say 1ns but the body of the article says 30ns (with hopes to eventually get it down to 5)?
- > Wi-Wi stands for Wireless 2Way interferometry
> 2Way
Does that mean you won't get to know the time unless you let them spy on your physical location too? That's what the diagram implies: https://www.gps.gov/sites/default/files/2025-06/CGSICMeeting...
GNSS time is still cooler because you can have extremely accurate time and a reading of your position without the broadcasting satellites knowing you're there.
by ProllyInfamous
0 subcomment
- When you drive through the Texas Pandhandle at night, squaremiles of electric windmills blink together – like fireflies stirring across flatlines of [L]one-star horizon.
They've been simultaneous for decades... and remains a breathtaking detour (if you're out there, schedule night-travel).
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I like the similar project which uses GPS signal offsets, captured on a RaspberryPi, to then broadcast (e.g:) a local-network-timeserver.
- I've wondered if you could have an array of "firecrackers", each timed very precisely, with perfect spatial knowledge of each, and synchronize their ignition to produce arbitrary shaped pressure waves.
- Most important question: Is it pronounced Why-Why, or Wee-Wee?
by CyborgCabbage
0 subcomment
- I've wondered if something like this could ever be used for VR tracking, though it seems it is much bulkier in than IR methods.
by wiradikusuma
3 subcomments
- Maybe silly question, why we care about nanosecond speed, don't we only need to sync once and the other system can count the time by itself?
by simulator5g
0 subcomment
- Better signal penetration with Wi-Wi could be a game changer for battery life.
by chrisallick
1 subcomments
- thats insane
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