Global Navigation Satellite Systems Engineering, Policy, and Design
The firefight between LightSquared and the GPS community has sparked regulatory brush fires around Washington with the Federal Communications Commission (FCC), Congress, a half dozen executive agencies, and numerous companies moving to address a new and likely larger battle over receiver standards, radio frequency spectrum efficiency, and RF spectrum protection.
By Dee Ann Divis
In-home construction of the first civilian-owned civil GPS spoofer.Over the last few years, several of us in the GNSS community have done our best to convince our colleagues, policymakers, and the general public that unsavory characters with GNSS jammers or spoofers are a genuine threat to GNSS and an orderly society.
"But who would want to use a jammer or spoofer?” people ask.
My response? Hackers, because they can. Thieves planning to snatch expensive cargo. A moonlighting employee in the company car. Worse yet, state actors or terrorists targeting our national infrastructure.
By Inside GNSS
The navigation message has always been considered an inherent and essential feature of a global satellite navigation system. Its primary objective is to provide receivers with information on the errors of satellite clocks and parameters to compute the positions of satellites, as well as other parameters that help generate more accurate measurements.
By Inside GNSS
The details of President Obama’s 2013 budget have been gradually filtering out and, in general, the GPS system and those programs closely linked to satellite navigation, have escaped deep cuts.
On the hardware side the White House has requested $58.2 for GPS IIF satellite procurement. According to Air Force budget documents, the plan is to then wrap up the total IIF procurement of 12 satellites with a request for $77.6 million in FY14 and $7.3 million in FY15.
By Inside GNSS
Return to main article: "Winging It"
GNSS technology is used in various ways to find attitude or trajectory. The simplest method relies on measuring the velocity of a single receiver and interpreting the direction of that vector as the vehicle’s heading.
This works for applications where a vehicle’s motion is constrained to only one axis – either absolutely, as with a train, or in the typical case of a car — when being driven responsibly!
By Inside GNSS
Return to main article: "Winging It"
With high-quality data sets obtained in the foot-to-foot configuration, we set about on postprocessing the data to extract more information about the NovAtel wingsuit system’s performance in the free-fall environment.
This was a multi-step process involving several NovAtel utilities and techniques, which we will describe here.
By Inside GNSS
Monte Mario, the highest hill in RomeA special seminar for geodesists will take place in Rome, Italy on May 4 and 5, just before the 35th FIG general assembly and working week.
The conference venue is the Cavalieri hotel on Monte Mario near the Vatican.
It is organized by the International Association of Geodesy (IAG), the surveyors’ international association (FIG) and the UN’s International Committee on GNSS (ICG).
By Inside GNSS
Return to main article: “Network RTK and Reference Station Configuration”
By Inside GNSS
Q: What effect does network size have on NRTK positioning?
A: Network real-time kinematic (NRTK) positioning is nowadays a very common practice, not only in academia but also in the professional world. In the last 10 years, several networks of continuous operating reference stations (CORSs) were created to support users. These networks offer real-time services for NRTK positioning, providing centimeter-level positioning accuracy with an average distance of 25–35 kilometers between the reference stations.
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.
Following a difficult 2009, the precision GNSS market is moving into a new period of sustained growth, resulting in a near doubling of shipments and revenues by 2016, according to recently completed study by ABI Research.
By Inside GNSS
Mark Greaves is one of two geodetic analysts at Ordnance Survey.
He holds an M.Sc. in engineering surveying and geodesy and is a member of the Royal Institute of Chartered Surveyors.
Greaves specializes in geodetic GNSS computations and analysis. He has worked at Ordnance Survey for almost 25 years during which time he has been responsible for several national GNSS network adjustments, including two internationally ratified realizations of the ETRS89 coordinate reference system in Great Britain.
By Inside GNSS
Paul Cruddace is the geodesy and positioning manager at Ordnance Survey, Great Britain’s national mapping agency.
He is responsible for the development and implementation of the overall strategy including the national GNSS infrastructure.
Cruddace is a chartered surveyor with a background in the use of precise GPS positioning to determine earthquake hazards.
By Inside GNSS
