Air Force Directs Early Civil Navigation (CNAV) Message-Populated L2C and L5 Signals

The U.S. Air Force is directing transmission of continuous CNAV message-populated L2C and L5 signals starting in April 2014. The move is designed to help development of user equipment compatible with the civil signals. Full text of the CNAV memo appears below.

MEMORANDUM FOR THE NATIONAL COORDINATION OFFICE FOR SPACE BASED POSITIONING, NAVIGATION AND TIMING

ATTENTION: DR. JAN BRECHT-CLARK

FROM: AFSPC/CC
Peterson AFB CO

SUBJECT: Early Civil Navigation (CNAV) Message-Populated L2C and L5 Signals

1. I have directed transmission of continuous CNAV message-populated L2C and L5 signals prior to fielding the Next Generation Operational Control Segment. This provision of populated signals will facilitate development of compatible user equipment and a CNAV Operations Concept.
2. The message-populated broadcast is projected to begin April 2014. Users should expect initial CNAV signal accuracy to be less than the legacy signals. Upon full implementation in December 2014, CNAV signal accuracy should meet or exceed the legacy signals.
3. Air Force Space Command is committed to ensuring GPS remains the world’s gold standard for PNT services. The user community can anticipate additional information on CNAV message implementation in the months preceding the initial April broadcast.

WILLIAM L. SHELTON
General, USAF
Commander