NOTICE: Due to a lapse in annual appropriations, most of this website is not being updated. Learn more.

Form submissions will still be accepted but will not receive responses at this time. Sections of this site for programs using non-appropriated funds (such as NVLAP) or those that are excepted from the shutdown (such as CHIPS and NVD) will continue to be updated.

U.S. flag

An official website of the United States government

Official websites use .gov
A .gov website belongs to an official government organization in the United States.

Secure .gov websites use HTTPS
A lock ( ) or https:// means you’ve safely connected to the .gov website. Share sensitive information only on official, secure websites.

PUBLICATIONS

Time and frequency dissemination using GPS: Recent improvements

Published

Author(s)

Tom Parker, Demetrios Matsakis

Abstract

This is an article for a general audience that reviews recent imporvements in time and frequency delivery by the Global Positioning System (GPS). A significant improvement in direct time delivery was achieved when Selective Availability (SA) was turned off in 2000. This has allowed time delivery to the civilian user at better than 100 nanoseconds accuracy if the user exercises reasonable care. More sophisticated users can make use of the phase of the microwave carrier of the GPS signal to achieve sub-nanosecond precision.
Citation
GPS World
Volume
15
Pub Type
Journals

Download Paper

Local Download

Keywords

frequency, GPS, satellite, time

Citation

Parker, T. and Matsakis, D. (2004), Time and frequency dissemination using GPS: Recent improvements, GPS World, [online], https://tsapps.nist.gov/publication/get_pdf.cfm?pub_id=50006 (Accessed October 11, 2025)

Issues

If you have any questions about this publication or are having problems accessing it, please contact [email protected].

Created October 31, 2004, Updated October 12, 2021
Was this page helpful?