Article 37542 of sci.geo.satellite-nav:
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From: Tom Van Baak <tvb@veritas.com>
Newsgroups: sci.geo.satellite-nav
Subject: Re: GPS and Relativity
Date: Mon, 05 May 1997 13:01:33 -0700
Organization: VERITAS Software
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References: <5kbtq1$7s4@senator-bedfellow.MIT.EDU> <336A2E2F.5F26@veritas.com>
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CC: "Robert S. White" <WhiteR@CRPL.Cedar-Rapids.lib.IA.US>,
	Hugues A Mathis <mathis@athena.mit.edu>
Xref: matra.meer.net sci.geo.satellite-nav:37542

Hugues A Mathis wrote:
> 
> Hi,
> 
>         Excuse-me for taking part of your time, but does anyone know what the
> ranges of relativistic corrections to GPS measurements are? (I mean, which order
> of magnitude)
>         Are the relativistic effects actually taken account of in current GPS
> measurements? If no do you think GPS could benefit from these corrections?
>         Thanks for your time and your answers,
> 
>         Hugh.

Sorry, my previous post (and both web pages I quoted) gave the
wrong frequency by one extra '9'. Robert's post looks correct.
The GPS SV clocks are set low by a factor of about 5e-10.

Page 13 of the official GPS SPS Signal Specification says the
output frequency is low by 4.567e-3 Hz, giving a frequency of
10.22999999543 MHz. The specification is available online at:
http://www.navcen.uscg.mil/GPS/reports/sigspec/sigspec.htm

GPS lecture notes by David Allan summarize the derivation of
the relativistic effect:
  -8.34e-11 from "2nd order doppler"
  52.79e-11 from "red shift"
for a total of 4.45e-10 (equivalent to 38.4 uSec/day).

/tvb