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From: nuchat!steve@uunet.UU.NET (Steve Nuchia)
Newsgroups: sci.military
Subject: Re: GPS Spoof
Message-ID: <6263@cbnews.ATT.COM>
Date: 5 May 89 00:35:01 GMT
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Organization: Houston Public Access
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From: nuchat!steve@uunet.UU.NET (Steve Nuchia)

In reference to the discussion of the relevance of the GPS
system to ballistic missle operation...

Note that the accuracy with which a mobile missle launcher
can hit a known, immobile target depends on how well the
launching platform knows its own position.  This, rather
than in-flight navigation, is the main importance of GPS to
ballistic missles.  Think about inertial navigation systems.
Think about long-term drift.  Think about nulling that drift
with high accuracy and confidence every now and then.

Cruise missles, on the other hand, may find it very
convenient to know their exact position rather than
perform a heuristic search through an 800Mb CD full
of Microsoft Flight Simulator (tm) scenery when they
loose track of the ground.
-- 
Steve Nuchia	      South Coast Computing Services
uunet!nuchat!steve    POB 890952  Houston, Texas  77289
(713) 964 2462	      Consultation & Systems, Support for PD Software.