GPS Selective Availability

Discussions focus on the historical US policy of Selective Availability that intentionally degraded civilian GPS accuracy, its discontinuation in 2000, and comparisons to other GNSS systems like GLONASS, Galileo, and BeiDou as backups or alternatives.

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Keywords

e.g US radioshack.com DOP state.edu gps.html ELI5 en.m DGPS GPS gps galileo satellites signal availability selective accuracy signals satellite precision

Sample Comments

jonknee • Jul 14, 2017 • View on HN

They share GPS, it used to be low-res but is now the real deal:https://en.wikipedia.org/wiki/Error_analysis_for_the_Global_...

lxgr • Oct 21, 2022 • View on HN

Selective Availability being phased out and is no longer a feature on the most recent GPS satellites:https://en.wikipedia.org/wiki/Error_analysis_for_the_Global_...

fanf2 • Nov 15, 2020 • View on HN

You are thinking of “selective availability” which was turned off over 20 years ago https://www.gps.gov/systems/gps/modernization/sa/

Asraelite • Mar 22, 2018 • View on HN

By "another GPS" do you mean a different satellite in the same network, or a different GNSS?

toomuchtodo • Dec 3, 2024 • View on HN

Any insight as to why newer GPS satellites do not offer similar capabilities?

manarth • Nov 4, 2017 • View on HN

The feature is called "Selective Availability", and has been disabled since May 2000.https://en.wikipedia.org/wiki/Error_analysis_for_the_Global_...

Natsu • Nov 18, 2011 • View on HN

Doesn't the government add a small amount of variance to the GPS signal to limit its accuracy for non-military users? Or did they stop doing that?

Laremere • Jun 3, 2023 • View on HN

GPS had this capability, and it was turned off: https://en.m.wikipedia.org/wiki/Error_analysis_for_the_Globa...

savimportweb • Jul 25, 2018 • View on HN

GPS is american, Europeans have the Galileo system, and the russians have glonass. aren't those a backup plan

rlanday • Sep 22, 2017 • View on HN

Civilian GPS signals used to have intentional error added, but that was ended in 2000:https://en.wikipedia.org/wiki/Error_analysis_for_the_Global_...