From owner-freebsd-hackers  Thu May  4  0:47: 0 2000
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Date: Thu, 4 May 2000 01:47:00 -0500 (CDT)
From: Kris Kirby <kris@hiwaay.net>
To: Matthew Dillon <dillon@apollo.backplane.com>
Cc: Warner Losh <imp@village.org>, hackers@FreeBSD.ORG
Subject: Re: GPS heads up 
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>      SA can *not* be averaged out.  People... SA is NOT NOISE.  I will
>      repeat that.  SA is NOT NOISE.  SA is an intentional error 
>      introduced by the satellites that looks like a drunk walking around
>      the town.  It takes a lot of readings over a long period of time
>      (read: at least a couple of days) for any sort of averaging to
>      yield a worthwhile result.

Two points:
1. The drunken walker idea is rather accurate if you look at a plot.
2. We've actually observed sine-wave like disturbances affecting the plot.
It was SA's induced error, plotted over a few hours.

-----
Kris Kirby, KE4AHR          | TGIFreeBSD... 'Nuff said.
<kris@nospam.hiwaay.net>    |    
-------------------------------------------------------
"Fate, it seems, is not without a sense of irony."



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