TAG: GPS Block IIF satellite

New GPS IIF Satellite Launched

February 21, 2014By
A United Launch Alliance Delta IV lifts off from Space Launch Complex-37 with the Air Force's Global Positioning System (GPS) IIF-5 satellite. This launch marked the 25th Delta IV flight since the first flight in 2002.

News compiled with the assistance of CANSPACE listserv. After a brief delay due to concerns over solar radiation trends, the GPS IIF-5 satellite was successfully launched at the end of the designated launch window at 01:59 UTC on February 21. The satellite, attached to the launch rocket’s upper stage, was initially placed in a highly elliptical orbit. Following a third... read more

GPS IIF-5 Launch Delayed

October 22, 2013By

The scheduled October 23 launch of GPS IIF-5, the fifth in the current “follow-on” generation of GPS satellites, has been postponed in order to complete a review of an adjustment made to the rocket’s upper stage engine. A fuel leak in that engine of the Delta 4 rocket during a GPS launch in October of last year created some worries... read more

Col. Bernard Gruber, GPS Directorate: Farewell Perspective on GPS Program

June 12, 2013By

I first met just-pinned-on, shiny and bright, Captain Bernard Gruber-USAF in 1992. Bernie had just arrived at the Space and Missile Systems Center at Los Angeles Air Force Base in California where he would hold several important positions. For those readers not aware of the mission and importance of the Space and Missile Systems Center (SMC), today SMC, which began... read more

Col. Bernie Gruber: Farewell Perspective on GPS Program

June 11, 2013By

This week’s Defense PNT newsletter by GPS World contributing editor Don Jewell carries an exit interview with Col. Bernard “Bernie” Gruber, who is leaving his post as director of the GPS Directorate after more than three and a half years in that position, and concluding his 26-year U.S. Air Force career. Look for the full interview later this week on... read more

The System: Galileo IOV Satellites Now in Orbit

November 1, 2011By

The first two satellites for Europe’s Galileo global navigation satellite system were lofted into orbit October 21 by the first Russian Soyuz vehicle ever launched from Europe’s Spaceport in French Guiana in a milestone mission, reports the European Space Agency (ESA). The launch occurred one day after initially scheduled to resolve a problem with the ground-support fueling system. The Soyuz... read more

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The System: GPS L5, the Real Stuff

July 1, 2010By
Fig.1 Carrier-to-noise-density ratio of GPS (left) and GIOVE-A/B signals measured at the Wettzell station on June 17, 2010. Red curves refer to signals in the L5/E5a band and include data from the PRN1 test satellite and the new PRN25 satellite.

The L5 signal of the new Block IIF satellite shows a very favorable signal strength (Fig. 1), which is somewhere in between the L1 and L2C signal strength for the employed antenna and slightly higher than that of the GIOVE-A/B satellites. While the L5 test signal of the second-last Block IIR-M satellite (PRN1/SVN49) is transmitted through a narrow beam antenna and shows a steep variation with elevation angle, the new satellite exhibits an almost constant flux irrespective of the boresight angle. read more

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Parkinson Prescribes Remedy for GAO Report Alarm

May 26, 2009By

Brad Parkinson, the first GPS Program Office director, chief architect and advocate for GPS, submitted written testimony to Congress on mitigation options for possible GPS brownouts. His presentation comes in reference to the recent GAO report highlighting the risk that the GPS constellation may fall below the minimum level of 24 satellites required for full operational capability. In his opening, Parkinson states that GAO correctly points out the possibility that the GPS constellation will be reduced to less than the current number of 30 to 32 satellites. In fact, it is possible that the constellation will be at a level of less than 24 satellites. I would like to focus on the options that would help reduce this risk." read more

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GPS at Risk: Doomsday 2010

May 12, 2009By

The United States Government Accountability Office (GAO) issued on May 7 an alarming report on the future of GPS, characterizing ongoing modernization efforts as shaky. The agency appears to single out the IIF program as the weak link between current stability and ensured future capability, calling into doubt whether the Air Force will be able to acquire new satellites in time to maintain current GPS service without interruption. It asserts the very real possibility that in 2010, as old satellites begin to fail, the overall GPS constellation will fall below the number of satellites required to provide the level of GPS service that the U.S. government commits to." read more

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