USAF Announces Initial Test Transmissions of L5 Signal from GPS IIF Satellite
June 10, 2010Officials from the Space and Missile Systems Center’s Global Positioning Systems Wing announced today that the first GPS IIF satellite, launched May 27, has begun test transmissions of the new Safety-of-Life (L5) navigation signal.
The L5 signal is a key element of efforts to modernize the GPS constellation for civil users. It was designed in close coordination with civil aviation and other organizations worldwide and is transmitted in a frequency band protected for safety-of-life applications. It will be transmitted from all GPS IIF and later spacecraft. GPS IIF is also designed to broadcast all of the signals on L1 and L2 frequency bands that users worldwide already receive from the rest of the GPS constellation.
Initial test transmissions from this latest GPS satellite (known as SVN-62) began June 5 as part of its on-orbit checkout phase. Test transmissions of the L5 signal from the spacecraft will take place intermittently, the Air Force said. Currently, the vehicle is set unhealthy to users and has the capability to transmit the new modernized Civil Navigation data message. These signals should not be used for navigation until the spacecraft is set healthy after the completion of approximately three months of on-orbit testing. At that point, a Notice Advisory to Navstar Users will be published and properly equipped GPS receivers will receive transmissions from this latest addition to the world’s premier space-based satellite navigation system.





