Re: Low cost method to increase the accuracy of GPS data

[TDC@ehssun.lbl.gov]

Actually the two GPS method COULD be useful but not exactly as you
describe.

SA (Selective Availablity) is not a discrete shifting but a continuous and
random wander at times as high a 2 miles/hr!  To average out SA takes a
reading as long as 8 hours to get to 2m accuracy.

So - occasional readings of the reference point won't do the job - but
simultaneous readings at the reference point and point of test will pretty
much cancel RA and leave only the variability of the unit itself.

Ted de Castro
tdc@ehssun.lbl.gov
University of California Lawrence Berkeley Laboratory
Bldg 75B Rm 112A
Berkeley, CA 94720
(510) 486-5256
(510) 486-5506 - FAX