Global Navigation Satellite Systems Engineering, Policy, and Design
The U.S. Air Force Space Command (AFSPC ) began testing modernized civil navigation (CNAV) message capabilities on the GPS L2C and L5 signals for the first time yesterday (June 15, 2013).
This first test period is scheduled to continue through July 1 (Julian Day 182), according to a Notice Advisory to NAVSTAR Users (NANU 2013034), although a tentative CNAV test plan shows the tests ending on June 29.
By Inside GNSS
[Updated June 3, 2013] With the budget vise tightening, top Pentagon managers are readying some potentially dramatic changes to the GPS constellation — changes that promise to lower both the cost of the satellites and the expense of putting them into orbit.
The first changes would be subtle and are linked to buying the next block of GPS III satellites — a decision that sources confirm will be made by the end of September.
By Dee Ann Divis
Jan Brecht-Clark, director, National Coordination Office for Space-Based Positioning, Navigation, and TimingWith just more than four months to go in the 2013 fiscal year, sequestration and furloughs are taking a bite out of key research and the work of the National Coordination Office (NCO) for Space-Based Positioning, Navigation, and Timing (PNT) — the government nexus for GPS-related policy matters.
The NCO is an interagency organization, explained its director, Jan Brecht-Clark in an emailed response; so, “each individual staff member is subject to furloughs implemented by their home agency as a result of sequestration.”
By Inside GNSS
The October entry in this EU-sponsored series of free GNSS training workshops concerns GNSS vulnerability. It will take place at the University of Nottingham on October 8, 9 and 10.
The instructors will be Terry Moore, Alan Dodson and Marcio Aquino, all faculty at University of Nottingham Geospatial Institute.
The topics:
GNSS Overview: Position fixing, dead reckoning, space segment and SV blocks, ground control and improvement programs,user segment and applications
By Inside GNSS
Existing methods for improving the GNSS performance commonly attempt to enhance the signal processing and navigation estimation parts of a single receiver. Such approaches, however, leave unexplored the potential benefits inherent to the integration of data from multiple receivers.
By Inside GNSS
Gen. William Shelton. DoD photoThe Air Force will decide this fall whether to build more GPS III satellites or move to a new generation of spacecraft, the leader of Air Force Space Command told Congress last week.
“We’re on contract right now . . . through (GPS III) satellite vehicle number eight. Satellite vehicles nine and beyond – the acquisition strategy for that – will be debated in the fall,” General William Shelton, commander of Air Force Space Command (AFSPC), told the House Armed Services Committee on April 25.
By Inside GNSS
Spending pressures on the Pentagon seem to be coming from every direction, and the GPS program appears unlikely to avoid them entirely.
The growing needs of veterans are poised to force up health care budgets and higher transportation costs and operating tempos have dug a $22 billion-hole in the accounts for Overseas Contingency Operations in places such as Afghanistan.
By Inside GNSS
A redesign of the GPS satellites under development by Lockheed Martin will add a signal waveform generator, search and rescue payload, laser retroreflector array (LRA), and dual-launch capability beginning with Space Vehicle 9 (SV09).
By Inside GNSS
President Obama has signed a continuing resolution, an omnibus federal spending measure that includes funding for the GPS program.
By Inside GNSS
One of 12 magnetograms recorded at Greenwich Observatory during the Great Geomagnetic Storm of 1859
1996 soccer game in the Midwest, (Rick Dikeman image)
Nouméa ground station after the flood
A pencil and a coffee cup show the size of NASA’s teeny tiny PhoneSat
Bonus Hotspot: Naro Tartaruga AUV
Pacific lamprey spawning (photo by Jeremy Monroe, Fresh Waters Illustrated)
“Return of the Bucentaurn to the Molo on Ascension Day”, by (Giovanni Antonio Canal) Canaletto
The U.S. Naval Observatory Alternate Master Clock at 2nd Space Operations Squadron, Schriever AFB in Colorado. This photo was taken in January, 2006 during the addition of a leap second. The USNO master clocks control GPS timing. They are accurate to within one second every 20 million years (Satellites are so picky! Humans, on the other hand, just want to know if we’re too late for lunch) USAF photo by A1C Jason Ridder. 
Detail of Compass/ BeiDou2 system diagram
Hotspot 6: Beluga A300 600ST
1. LATE LAUNCHES
Cape Canaveral and Plesetsk
√ [updated April 1] After three delays, a single GLONASS-M satellite will go up from Plesetsk space center on April 26. The United States will send up SVN66, the fourth GPSIIF satellite— on an Atlas V launcher for the first time—during the early evening of May 15. It had been delayed from March.
TABLE 1: Deployment Status Note: Two types of clocks on board: PHM = Passive Hydrogen Maser, RAFS = Rubidium Atomic Frequency StandardEurope’s new age of satellite navigation has passed a historic milestone — the very first determina-tion of a ground location using the four Galileo satellites currently in orbit together with their ground facilities.
This fundamental step confirms the Galileo system works as planned.
By Inside GNSS
Working Papers explore the
technical and scientific themes that underpin GNSS programs and
applications. This regular column is coordinated by Prof. Dr.-Ing. Günter Hein, head of Europe’s Galileo Operations and Evolution.
Deep military spending cuts set to kick in March 1 will likely slow efforts to modernize the GPS constellation, insiders agree, in large part because many of the personnel needed to push the program forward will be sitting at home, unpaid, one day out of every five.
The human impact of the deep cuts taking effect when sequestration kicks in on Friday was already evident in mid-February during the program review conference held by the Association for Unmanned Vehicle Systems International.
By Inside GNSS
