Change to GPS Operational Advisory Message
Written by CGSIC   
Monday, 02 April 2018

The Global Positioning Systems Directorate will propose a change to the Navstar GPS Control Segment to User Support Community Interfaces (ICD-GPS-870), Interface Control Documents that will remove Section One (1) from the GPS Operational Advisory.

Background: The GPS Operational Advisory is a message generated by the GPS Control Segment on a daily basis. It provides a snapshot of the GPS operational constellation:

Section 1: satellites (by PRN), plane / slot assignments, and the operational clock
Section 2: a summary of current advisories, forecasts, and general text messages
Section 3: remarks section identifies points of contact for additional technical and support information

Coast Guard Navigation Center distributes this message on a daily basis to over 4000 subscribers and posts the files to the web. NAVCEN also maintains an archive of these messages on the NAVCEN website.

At the next Public Interface Control Working Group, the GPS Directorate will propose the removal of Section One (1) (satellite plane/slot assignments) from the Operational Advisory message. This means plane/slot and clock information will no longer be available on a daily basis through the subscription service provided by NAVCEN.

If you use the Operational Advisory message, or the Section 1 information contained within the message, please use the Contact form found on NAVCEN’s website (https://www.navcen.uscg.gov/?pageName=contactUs, select CGSIC from the subject dropdown menu) to let us know how the loss of this information would impact your operations. The CGSIC will compile responses from the community and provide them to the GPS Directorate in advance of the next GPS Public Interface Control Working Group.

The GPS Public Interface Control Working Group is open to all GPS users. The date of the 2018 GPS Public Interface Control Working Group will be announced through CGSIC and GPS.gov once the GPS Directorate has published the dates.

You can find a copy Navstar GPS Control Segment to User Support Community Interfaces (ICD-GPS-870), Interface Control Documents at GPS.gov (https://www.gps.gov/technical/icwg/) and on NAVCEN’s webpage in the Technical References section (https://www.navcen.uscg.gov/?pageName=gpsTechnicalReferences).