Global Navigation Satellite Systems Engineering, Policy, and Design
AGNSS Technique. Nokia graphicFinland’s Nokia, the world’s leading manufacturer of mobile phones, is investigating use of GLONASS signals in new products that could reach the market in the near future.
By Inside GNSS
The GPS constellation, as illustrated 30 years ago.While awaiting the arrival of the definitive history of the Global Positioning System, students of the premier GNSS program might want to take a look at a systems engineering case study released last month by the Center for Systems Engineering at the Air Force Institute of Technology (AFIT), Wright-Patterson AFB, Ohio.
By Glen Gibbons
The U.S. Air Force launched the fifth modernized GPS Block II Replenishment (IIR-M) satellite at 3:04 p.m. EST (20:04 UTC) December 20 from Cape Canaveral Air Force Station, Florida, (December 20) aboard a United Launch Alliance Delta II rocket. Air Force controllers set the spacecraft to "healthy" status on January 2, in what is probably a record time of 13 days.
By Glen Gibbons
The U.S. Air Force has exercised new options on contracts with three companies for development of GPS Modernized User Equipment (MUE) for future military applications.
Under the new awards, Raytheon will receive $65 million; Rockwell Collins, $50.7 million; and L-3/Interstate Electronics Corporation, $36 million. All options were awarded on or about October 19.
By Glen Gibbons
SpringerGeosciences has announced release of the latest book by Bernhard Hofmann-Wellenhof: GNSS — Global Navigation Satellite Systems: GPS, GLONASS, Galileo & More. Coauthors are Herbert Lichtenegger and Elmar Wasle.
By Inside GNSS
CAST Navigation VIP simulatorSimulators from CAST Navigation, Billerica, Massachusetts USA, that are being used in government and military labs around the world will now be made available to commercial markets, the company has announced.
By Glen Gibbons
Boeing technicians and first Block IIF satelliteThe Boeing Company has successfully assembled and integrated all flight hardware onto the first GPS Block IIF (follow-on generation) satellite. Launch is now scheduled for the second half of 2008.
GPS llF spacecraft will bring new capabilities to the GPS constellation, such as a new encrypted military code, a new civil signal, crosslink enhancements, increased signal power, and longer design life. Boeing is building 12 GPS Block IIF satellites under contract from the GPS Wing at the Space and Missile Systems Center at Los Angeles Air Force Base.
By Glen Gibbons
GLONASS has gotten “preliminary approval” to add code division multiple access (CDMA) signals to future satellites.
Since its initiation in the early 1980s, the Russian GNSS system has employed frequency division multiple access (FDMA) techniques in which the same code is used for the signals broadcast by the system, with individual spacecraft being distinguished from one another by a specific frequency allocation. Russia would almost certainly continue broadcasting FDMA signals on existing frequencies.
By Glen Gibbons
Selective Availability (SA), the contentious issue of degrading the open GPS civil to advantage military signals, is going away for good under the terms of a presidential decision announced September 18.
By Glen Gibbons
On September 14, Air Force crews at Schriever AFB, Colorado, completed the initial phase of an $800 million upgrade to the GPS operational control segment.
Operators in the 2nd Space Operations Squadron (2SOPS) of the USAF 50th Space Wing migrated control of the GPS satellite constellation and ground monitoring facilities from a 1970s-era mainframe computer to a distributed IT infrastructure with advanced automated features. The 50th Space Wing, through the 2nd SOPS, performs the satellite command and control mission for the Global Positioning System.
By Inside GNSS
The United States and the European Union (EU) have agreed to use the multiplexed binary offset carrier (MBOC) for a common GPS-Galileo signal for civilian use. In the future, this will enable combined GNSS receivers to track the GPS and Galileo signals with higher accuracy, even in challenging environments that include multipath, noise, and interference.
These signals will be implemented on the Galileo Open Service and the GPS IIIA new L1 civil signal known as L1C.
By Inside GNSS
Researchers at Cornell University recently released their analysis of the effects of solar radio bursts (SRBs) during a solar flare last December that produced “unprecedented” fades in received GPS signal power at L1 and L2 over an extended period.
By Inside GNSS
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.
By Inside GNSS
