[sci.electronics] GPS error to be reinserted

commgrp@silver.ucs.indiana.edu (BACS Data Communications Group) (06/28/91)

Last night I heard on WWV's GPS status report (15 minutes after the hour) 
that selective availability will be reinstated within the next few days.

"Selective availability" (SA) is an encrypted intentional error introduced 
into the satellite navigation signals, ostensibly to keep enemies from 
using the system.  However, SA was turned OFF last August at the beginning 
of the "Gulf Crisis."   Apparently, there were not enough military-grade 
GPS receivers available so they pressed civilian units into service.

There were rumors that SA would be left off permently due to political 
pressure from civilian and nonmilitary government GPS users.  The WWV 
report is bad news, especially now that GPS receivers will soon reach the 
$1000 class.

The Omega (VLF navigation system) status report on WWV (immediately 
following GPS) said that Omega may have 2-4 nautical-mile error during the 
solar eclipse.  Can any propagation experts comment on that?

--

Frank Reid    W9MKV     reid@ucs.indiana.edu

bender@oobleck.Eng.Sun.COM (memory fault - core dumped) (06/29/91)

In article <1991Jun28.144253.8992@bronze.ucs.indiana.edu> commgrp@silver.ucs.indiana.edu (BACS Data Communications Group) writes:
->Last night I heard on WWV's GPS status report (15 minutes after the hour) 
->that selective availability will be reinstated within the next few days.
->
->"Selective availability" (SA) is an encrypted intentional error introduced 
->into the satellite navigation signals, ostensibly to keep enemies from 
->using the system.  However, SA was turned OFF last August at the beginning 
->of the "Gulf Crisis."   Apparently, there were not enough military-grade 
->GPS receivers available so they pressed civilian units into service.

This is disturbing, especially in light of the recent news reports that the
US may be considering starting to bomb Iraq again.

If only our elected (?) officials read net.news...  Or, maybe they DO read
it, but just rec.bomb.other.nations...

mike
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1985 Honda Shadow VT1100                                   | DOD #000007
1989 Honda NX-650                                          | AMA #511250