[time-nuts] Spacecraft Timekeeping

[ehydra]

There are is a list on a ballooner website with GPS devices working 
beyond export rules.


- Henry

-- 
ehydra.dyndns.info



Magnus Danielson schrieb:
> First thing to consider is that standard GPSes will not meet your needs, 
> since they have to obey the height and speed limits for export rules.
> 
> The side-effect is that doppler frequencies may be much higher and both 
> tracking and acquisition needs to include these more extremer doppler 
> frequencies.
> 
> Use of PTP within a rocket or spacecraft may or may not be a good thing. 
> NMEA + PPS may suffice and be less power-hungry. IRIG may also be an 
> option.
> 
> If timing and frequency needs strict correlation with ground, relativity 
> comes into play due to altitude alone shifts frequency.
> 
> Cheers,
> Magnus