I'm looking for a timing GPS now.

You didn't mention your budget.

But, all of the GPS solutions require lots of power, although it's 
easily accurate to within 1 us. OEM modules can be had for 25 to 70 
dollars each though, so perhaps this is viable.

GL

Art





At 10:54 AM 10/14/2006, you wrote:

>Stupid me. Although particularly obvious, this had totally passed me by,
>I'm so use to saving power where I can, it comes automatically to me now!!
>
>I think this combined with a GPS reciever could be the solution to all my
>problems!
>
>As to why they need to be that synced, (thats a secret :P). I've
>questioned the spec a few times, but I'm told it's necessary by the powers
>that be.
>
>Mat
>
>
> > Maybe I missed something - this sounds too easy.
> >
> > Power at the transmitter is effectively unlimited, right? (o.k. 11 watts,
> > but that's still lots) Why not just send a time signal out continuously,
> > and let the receiver read it whenever it wakes up? The transmitted data
> > stream could be a time packet followed by some form of sync pulse -
> > something like $5A5A, then the reciever snychronizes with the next rising
> > edge.
> >
> > I'm more interested in why the units need that level of sync.
> >
> > -Denny
> >
> >
> >
> >
> >> I'm currently working on a design with a specific problem, which I'm
> >> hoping someone will have come across before.
> >>
> >> Essentially I have several remote circuits, which must remain
> >> unconnected.
> >> They all need to be synchronised within 100 Micro Seconds.
> >>
> >> Essentially we are looking at deploying a beacon transmittor which will
> >> send out a pulse at known intervals and have low power recievers on each
> >> circuit which come out of hibernation at the required interval, to reset
> >> the onboard clocks appropiatly.
> >>
> >> We are looking at achieving 100m range (indoors), however power at the
> >> beacons is not a significant problem (we have 11Watts available, and
> >> these
> >> are not battery powered). Power at the recievers is crucial, each
> >> circuit
> >> is powered by battery and must be capable of running for a minimum
> >> period
> >> of a year. Physical battery size is not crucial but small is better :)
> >>
> >> Does anyone have any other suggestions how to achieve the required
> >> synchronisation, or can anyone suggest any suitable radio IC's/circuits
> >> which could be used as I am stuggling to find anything useful via google
> >> (must be using the wrong keywords)
> >>
> >> Any suggestions or comments would be greatly appreciated.
> >>
> >> Mat
> >>
> >>
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