[time-nuts] Distance between GPS Antennae

[Poul-Henning Kamp]

In message <4EEE53C3.4060701 at adobe-labs.com>, Brent Gordon writes:

>   This is using a GPS from Sure Electronics.  Note that the standard
>   deviation is 0 for over 100,000 samples.  As a side note, it must have
>   some kind of heavy filtering going on to not show any position
>   variation.

Some newer GPS's have a built in accelerometer chip and will apply
much more rigid filters if no motion is detected.  If done well,
it works great, if done badly you tap your GPS receiver lightly
and the position jumps 50 meter in a random direction.

-- 
Poul-Henning Kamp       | UNIX since Zilog Zeus 3.20
phk at FreeBSD.ORG         | TCP/IP since RFC 956
FreeBSD committer       | BSD since 4.3-tahoe    
Never attribute to malice what can adequately be explained by incompetence.