GNSS & the Law

November 20, 2016

GPS for Everyone

GPS seems to have come out of nowhere. There was no progression like eight-track tape to cassette to CD to MP3 player. One day we were driving around clueless of where we were, struggling with roadmaps bought as gas stations that couldn’t be folded back neatly once opened and — suddenly — there was an amiable female voice coming out of the dashboard offering directions to our destination and showing no signs of impatience when we made wrong turns.
From the author’s introduction to GPS for Everyone

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By Inside GNSS

Challenges of Ray-Tracing for GNSS Applications

Figures 5 – 8

Q: What are the challenges of ray-tracing for GNSS applications?

A: Simulating the propagation and reception of GNSS signals in complex environments is a challenging task. Indeed, the user always has to trade off between the computation time and the reliability of the output. Moreover, the motion of GNSS satellites, atmospheric effects, and building geometry are always difficult to model.

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By Inside GNSS
September 16, 2016

Defeating ‘Death by GPS’

Park rangers in Death Valley National Park have begun calling it “death by GPS.” Visitors faithfully following their navigation devices turn down the wrong road or hike away from help and die before rangers can reach them.

But it really isn’t the GPS, it’s the maps in their navigation system’s database.

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By Dee Ann Divis
September 9, 2016

Changing the Rules

How do you win when you are really losing?

Play a different game, move the goalposts, change the rules.

For several years now, a series of would-be wireless broadband service providers have been attempting to convince the Federal Communications Commission (FCC) to repurpose radio frequency spectrum near the GPS L1 band.

Past efforts have failed because of the transmissions’ demonstrated harmful effects on GPS and other GNSS signals. Now a new contender is trying to gain FCC’s approval by changing the way that those effects are measured.

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By Inside GNSS

GNSS Hotspots

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. BREXIT
Harwell Didcot, United Kingdom

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By Inside GNSS
September 8, 2016

Mikel Miller’s Compass Points

Mikel Miller’s favorite equation

Return to main article: "Mikel Miller: Science, Service, and Family"

COMPASS POINTS

GNSS event that most signified to you that GNSS had ‘arrived’

Testing of the initial handheld units from vendors such as Trimble’s two-channel GPS receiver and Rockwell Collins’ PLGR. “We thought, ‘What an amazing capability to have a handheld device that all you had to do was turn it on and it told you where you were – wow!’”

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By Inside GNSS
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