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Homeland Security Steps Up to Protect GPS (But Not from LightSquared)

After a long series of fits and starts, the Department of Homeland Security is tackling the issue of interference to the GPS signal. The agency has launched a study to assess the risks to GPS service from a variety of sources — a study that, at least on paper, will lead to a plan to mitigate interference.

Unfortunately, the effort will not directly address the one potential problem consuming the thoughts of the GPS community — widespread receiver overload from the high-powered mobile broadband service proposed by the Virginia firm LightSquared.

By Dee Ann Divis

April 18, 2011

Keeping the Spoofs Out

The demand for techniques capable of authenticating the GNSS signals and detecting simulation attacks (spoofing) has increased exponentially in the last years, mainly targeted to financial and safety critical applications.

Associated proposals and developments addressing these issues focused on two different approaches: user segment authentication services that leveraged existing services in order to detect signal spoofing and that integrated signal authentication services into the GNSS system itself.

By Inside GNSS

Modernization Times

Enterprise Baseline Schedule

Col. Bernie Gruber, commander of the GPS Directorate since June 2010, works in a busy place.

Through its various incarnations since being established in 1974 — as Joint Program Office, Air Force Wing, and now Directorate — the GPS program at the Space and Missile Systems Center (SMC), Los Angeles Air Force Base, California, has been at the center of the action.

By Inside GNSS

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Finding the Interference

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.

By Inside GNSS

March 23, 2011

GNSS Hotspots | March 2011

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. NORTHERN LIGHTS
Northern Hemisphere

√ The sun has been in a feisty mood lately, with solar flares mid-February to mid-March. GNSS signals haven’t been affected, because these plasma ejections have magnetic fields that are parallel to Earth, instead of perpendicular to it. That could change suddenly, according to the Space Weather Prediction Center. (Meanwhile, the Northern Hemisphere has enjoyed brilliant auroras.)

By Inside GNSS