From: isdale@illusioninc.com (Jerry Isdale)
Subject: TECH:  re: GPS in helmet tracking?
Date: Fri, 29 Mar 1996 10:14:06 -0800


A differential GPS receiver could give you very good position
accuracy, IF you are out doors, away from trees, overhangs, etc. and
dont mind waiting a few tenths of a second to get a fix.  The GPS
signal does not penetrate buildings or foliage. It also is hard to use
in "urban canyon" areas, due to the shadow of the buildings.

Other than that, GPS might work ok.  Could be really useful if you are
trying to do augmented reality in a really big space.

Jerry Isdale
Illusion Engineering, Inc.
2660 Townsgate Rd., Suite 530, Westlake Village, CA  91361-2714
Phone:          (805) 371-4530        FAX:    (805) 371-4533
Internet:       isdale@illusioninc.com