U.S. Air Force officials are moving quickly to turn on the new civil GPS L5 signal after lengthy delays due to technical problems had brought the program close to an International Telecommunications Union (ITU) deadline for transmitting on the frequency.

The Air Force plans to begin transmitting the signal at 5 a.m. (PDT) on April 10 using the Block II R-20(M) satellite launched March 24. An L5 signal demonstration is planned the same day, organized by the GPS Wing and SRI International. The L5 spectrum will be received and plotted at the SRI’s 150-foot “big dish” antenna facility in the hills over looking Stanford University, California.

U.S. Air Force officials are moving quickly to turn on the new civil GPS L5 signal after lengthy delays due to technical problems had brought the program close to an International Telecommunications Union (ITU) deadline for transmitting on the frequency.

The Air Force plans to begin transmitting the signal at 5 a.m. (PDT) on April 10 using the Block II R-20(M) satellite launched March 24. An L5 signal demonstration is planned the same day, organized by the GPS Wing and SRI International. The L5 spectrum will be received and plotted at the SRI’s 150-foot “big dish” antenna facility in the hills over looking Stanford University, California.

Another group, including members of the Stanford University GPS Laboratory, will use the university’s two-meter dish to collect L5 transmission data using a variety of commercial GPS receivers while the signal is available until SVN49 “sets” at about 9 a.m. (PDT). Inside GNSS will publish articles by member of the GPS Lab on the L5 demonstration in the near future.

The IIR-20(M) — now known as Space Vehicle Number 49 (SVN49) — has been transmitting on the L1 frequency since earlier this month.

Intended for safety-of-life applications including civil aviation, the GPS L5 signal is located in an aeronautical radionavigation service (ARNS) band centered at 1176.45 MHz. Compared to legacy GPS signals, including the L1 C/A-code, L5 has an improved signal structure, higher transmitted power (about 3dB), wider bandwidth, and longer spreading codes.

The post GPS L5 Signal Goes on the Air April 10 appeared first on Inside GNSS - Global Navigation Satellite Systems Engineering, Policy, and Design.

The U.S. Air Force has awarded Lockheed Martin Company a $6 million contract to develop and integrate a demonstration payload that will temporarily transmit an L5 civil signal on a modernized GPS Block IIR (GPS IIR-M) satellite.

Meanwhile, a request for proposals (RFP) was released in mid-April for the next-generation Block III space segment contract. An RFP for the GPS was released to industry on February 23.

This new L5 contract directs Lockheed Martin and its navigation payload supplier ITT in Clifton, N.J., to provide an on-orbit demonstration capability for the new civil signal located on the L5 frequency (1176MHz). The Block IIR-M spacecraft with the demonstration payload is planned for launch in 2008.

L5 will be a regular part of the GPS signals transmitted by the follow-on GPS satellites (Block IIF) being built by Boeing Company. The first IIF launch is also scheduled for next year.

“We are pleased the Air Force has entrusted Lockheed Martin to provide this important on-orbit demonstration on a Block IIR-M spacecraft,” said Don DeGryse, Lockheed Martin’s vice president of navigation systems.

Lockheed Martin Space Systems, Valley Forge, Pa., is the prime contractor for the GPS IIR program. The company designed and built 21 IIR spacecraft for the GPS Wing (formerly the NAVSTAR GPS Joint Program Office), Space and Missile Systems Center, Los Angeles Air Force Base, California.

With the first launch nearly 10 years ago, all of the 15 IIR satellites activated to date are still operating on orbit.

The final eight spacecraft, designated Block IIR-M, were modernized to enhance operations and navigation signal performance for military and civilian GPS users around the globe. ITT supplied all 21 navigation payloads for both the IIR and IIR-M spacecraft.

GPS Wing Leadership to Change.

The GPS Wing will have a new leader this summer, when Col. David Madden becomes the commander there, replacing Col. Wesley “Al” Ballenger.

Madden became vice-commander of the GPS Wing in July 2006. Although his return to Los Angeles AFB is recent, Madden has had previous experience in GPS-related programs. From July 2001 to September 2002, he was the Combat Survivor Evader Locator (CSEL) program manager, at GPS JPO and then, until July 2004, chief of the Command, Control, Communications and Navigation Division, Directorate of Requirements, in Air Force Space Command headquarters at Peterson Air Force Base, Colorado.

Copyright 2007 Gibbons Media and Research LLC

The post USAF Lets L5 Demo Contract; GPS III RFPs appeared first on Inside GNSS - Global Navigation Satellite Systems Engineering, Policy, and Design.