nanog mailing list archives
Re: GPS SA and Network Timing
From: Owen DeLong <owen () delong sj ca us>
Date: Wed, 26 Sep 2001 09:44:13 -0700
Robert E. Seastrom wrote:
"Hire, Ejay" <Ejay.Hire () Broadslate net> writes:In our next episode of Militant dictator How-to, we'll show you how to upgrade an antique scud missile to with a guidance system capable of 3-meter accuracy for less than $500.00 per unit.. Stay tuned!Somehow, I find it difficult to believe I'm dignifying this with aresponse (much less a public one), but here goes:Every commercial GPS unit that I have ever seen has a speed which, if exceeded, will cause the unit to shut down (usually until power-cycled). It varies from unit to unit, but in every observed case was substantially (several times) less than the speed of such weaponry in flight. Commercial units also have altitude limits, with the same consequences for exceeding them. Integrating an OEM GPS module with existing avionics systems' targeting mechanism so it can actually cause the missile to adjust its course is left as an exercise to the local defense systems integrator.
I know my Garmin 195 functions in real life up to about 462 knotts. I don't know what it's shutdown point for real life is, as I haven't ever been able to deploy it in an environment going faster than that. I also know that in simulator mode, it is good to about 1000 knotts. If I remember correctly, the SCUD is subsonic. As such, I believe the Garmin would handle it.
Resist the cycle of content-free posts to NANOG... ---Rob
Owen -- *********************************************************************** "Every time you turn on your new car, you're turning on 20 microprocessors. Every time you use an ATM, you're using a computer. Every time I use a settop box or game machine, I'm using a computer. The only computer you don't know how to work is your Microsoft computer, right?" - Scott McNealy, CEO of Sun Microsystems, Inc., from an April 1997 interview in Upside Magazine *********************************************************************** "One World, One Web, One Program." - Microsoft Promotional Ad "Ein Volk, Ein Reich, Ein Führer" - Adolf Hitler
Current thread:
- GPS SA and Network Timing Eric Germann (Sep 26)
- Re: GPS SA and Network Timing Robert E. Seastrom (Sep 26)
- Re: GPS SA and Network Timing Marshall Eubanks (Sep 26)
- <Possible follow-ups>
- RE: GPS SA and Network Timing Ian A Finlay (Sep 26)
- Re: GPS SA and Network Timing David Lesher (Sep 26)
- Re: GPS SA and Network Timing Valdis . Kletnieks (Sep 26)
- Re: GPS SA and Network Timing E.B. Dreger (Sep 27)
- Re: GPS SA and Network Timing David Lesher (Sep 26)
- RE: GPS SA and Network Timing Hire, Ejay (Sep 26)
- Re: GPS SA and Network Timing Robert E. Seastrom (Sep 26)
- Re: GPS SA and Network Timing Owen DeLong (Sep 26)
- Re: GPS SA and Network Timing Joel Jaeggli (Sep 26)
- Re: GPS SA and Network Timing Hank Nussbacher (Sep 27)
- Re: GPS SA and Network Timing Robert E. Seastrom (Sep 26)
- Re: GPS SA and Network Timing Wolfgang Henke (Sep 26)
- Re: GPS SA and Network Timing Marshall Eubanks (Sep 26)
- Re: GPS SA and Network Timing Randy Bush (Sep 26)
- Re: GPS SA and Network Timing Howard C. Berkowitz (Sep 26)
- Re: GPS SA and Network Timing Petr Swedock (Sep 26)