[time-nuts] Need advice for multilateration setup

[Magnus Danielson]

Remember, that if you have 4 receivers you get X, Y, Z and T of the 
source, and in this case T will be the phase-drift of the rocket. So, if 
logged with sufficient precision, the stability of the on-board clock 
may not become as important as the fact that it is there and has 
reasonably good phase-noise. That however, might be an issue for 
sounding-rockets, but can be addressed to some degree by mounting.

Cheers,
Magnus

On 03/28/2015 01:25 PM, Peter Reilley wrote:
> Some crystal oscillators specify their sensitivity to G forces.
> Here is one:
> http://www.abracon.com/Precisiontiming/AOCJYR-24.576MHz-M6069LF.pdf
>
> Available here:
> http://www.digikey.com/product-detail/en/AOCJYR-24.576MHZ-M6069LF/535-12627-
> 1-ND/4989033
>
> Others specify shock and vibration limits but say nothing about
> frequency stability.
>
> Pete.
>
>
> -----Original Message-----
> From: time-nuts [mailto:time-nuts-bounces at febo.com] On Behalf Of Chris
> Albertson
> Sent: Friday, March 27, 2015 9:55 PM
> To: Discussion of precise time and frequency measurement
> Subject: Re: [time-nuts] Need advice for multilateration setup
>
> On Fri, Mar 27, 2015 at 10:29 AM, Chuck Harris <cfharris at erols.com> wrote:
>
>> The biggest problem I see is the crystal oscillator in the rocket is
>> going to notice the G forces during acceleration in a pretty big way.
>
>
> But all of the ground stations will see the same frequency shift on the
> rocket's transmitter.   I think this can be backed out in processing.
>
> Someone needs to write the equations and post them here.
>