United States Air Force and SRI International Successfully Transmit an L5 Signal from the Global Positioning System IIR-20(M) Satellite
Los Angeles Air Force Base, El Segundo, Calif. —April 10 , 2009— The U.S. Air Force GPS IIR-20(M) satellite successfully transmitted for the first time a GPS signal in the L5 frequency band at 5:00 a.m. PDT, April 10, 2009. L5, the third civil GPS signal, will eventually support safety-of-life applications for aviation and provide improved availability and accuracy. This broadcast brings into use the GPS International Telecommunication Union (ITU) filing at 1176.45 MHz in the highly protected and co-allocated Radionavigation Satellite Service (RNSS) and Aeronautical Radionavigation Service (ARNS) band.
A joint team consisting of the GPS Wing, Lockheed Martin, ITT, and The Aerospace Corporation developed the "L5 Demonstration" signal payload and integrated it onto the GPS IIR-20(M) spacecraft, which was launched on March 24, 2009. The initial broadcast of the L5 Demonstration signal was monitored and validated by SRI International in Menlo Park, CA, in cooperation with the GPS Wing, 2nd Space Operations Squadron (2SOPS), Lockheed Martin, Draper Laboratory, and the MITRE Corporation.
Figure 1, above, illustrates the time series and power spectrum plots for the L5 Demonstration Signal as seen from SRI's 150-foot radio antenna ("The Dish") and confirms the L5 signal power and modulation.
"Thanks to the men and women of the Air Force, our industry partners and national research institutes, this morning's successful L5 transmission marks an important milestone in GPS civilian applications. This new third civil signal will make possible the research and development of safety-of-life applications for the commercial transportation sector, and in the future, will play a vital role in improving safety, fuel efficiency, and capacity in our airspace, waterways, highways, and railroads. Today's event marks another important step in the ongoing effort to maintain and modernize GPS as the global standard for space-based positioning, navigation, and timing," said Mr. Joel Szabat, Deputy Assistant Secretary for Transportation Policy, Department of Transportation.
"The L5 demonstration payload effort shows the can-do spirit and dedication of all who work in this industry and is an example of a government/industry team working together to meet a significant challenge in a very short time. Development of a solid plan and schedule, adherence to that plan, and consistently looking ahead allowed for a timely and successful completion of the L5 effort," said Col. Dave Madden, Commander, Global Positioning Systems Wing.
The Space and Missile Systems Center, located at Los Angeles Air Force Base, Calif., is the U.S. Air Force's center of acquisition excellence for acquiring and developing military space systems including six wings and three groups responsible for GPS, military satellite communications, defense meteorological satellites, space launch and range systems, satellite control network, space based infrared systems, intercontinental ballistic missile systems and space situational awareness capabilities. SMC manages more than $60 billion in contracts, executes annual budgets of over $10 billion and employs more than 6,800 people worldwide.
