Satellite Navigation graphic showing various satellite navigation applications

Final Notice on Codeless and
Semi-Codeless Access to GPS

On May 16, 2008, the Office of Space Commercialization published a notice in the Federal Register requesting public comments on the U.S. Government's plan to phase out codeless and semi-codeless access to GPS by December 31, 2020. The government seeks to encourage the users of codeless/semi-codeless technology to migrate to new GPS equipment utilizing the next-generation signals known as L2C and L5. The transition plan will have no effect on users of consumer GPS devices that use the basic civil signal known as C/A on L1.

View the request for comments in the Federal Register...

The comment period closed on June 16, 2008. All comments received have been posted on this page for public viewing. The Office of Space Commercialization reviewed the comments and used them to inform government discussions regarding the transition plan for codeless and semi-codeless GPS access.

On September 23, 2008, the Department of Defense issued a final notice committing to continue supporting codeless/semi-codeless GPS access until December 31, 2020.

View the final notice in the Federal Register...

On December 28, 2009, Gen. Robert Kehler of Air Force Space Command issued a letter to the civilian community confirming the Air Force's intent to comply with the 2008 Federal Register notice and to document a commitment to phase stability for the new civil GPS signals.

View the Gen. Kehler letter...

In August 2010, the Air Force followed up by publishing updates to the GPS Interface Specification documentation. Among other things, the new documentation establishes a baseline phase relationship for the L2C signal.

Learn more at


The external links below provide additional information about key U.S. Government programs, organizations, and documents referenced in the Federal Register notice.

Media Articles

The following articles from the trade press offer additional perspectives on the codeless/semi-codeless transition plan.

Public Comments Received

The Office of Space Commercialization does not endorse the views of any individual person, company, association, or organization whose comments are provided here. Some files have been posted in Portable Document Format (PDF) and may require you to download the free Acrobat Reader.