In July, a solar car racing team from the University of Michigan won
the North American Solar Challenge (NASC) with Continuum, a sun-powered
vehicle that averaged 46 miles per hour over the 2,400 miles from
Plano, Texas, to Calgary, Alberta. It wasn't easy - GPS support
vehicles used real-time simulations from a GNSS survey of the entire
course to give the high-maintenance Continuum good advice - such as
when to get out from under the clouds and back into the
First of three stories about Galileo's new signals in space
Earlier this year, Galileo’s second experimental satellite reached
orbit and began broadcasting a wide range of signals, including the
first transmissions of the new composite BOC signal on the L1
In the first of three stories about Galileo's new signals in space, this article provides an initial report of GIOVE-B
observations performed at the Chilbolton Observatory in the United
Kingdom during May and June 2008.
Second of three stories about Galileo's new signals in space
The multiplex binary offset carrier (MBOC) was chosen as the optimal
common open civil signal waveform at the L1 frequency for both GPS and
Galileo, in large part because of its anticipated advantage in
mitigating the effects of multipath (reflected signals). Turns out
those expectations were correct, according to observations made by this
team of researchers.
Third of three stories about Galileo's new signals in space
The prospects are good for carrier phase integer ambiguity resolution
through double differencing signals from the first two Galileo
experimental satellites (GIOVE-A and GIOVE-B), with accuracies at the
Once again the world is becoming a cauldron of grievances involving its
most powerful nations, including the four primary members of the ICG
The aerospace engineering professor has contributed to RAIM, GPS bistatic radar, satellite formation flying using GPS, GPS-based orbit and satellite attitude determination, and multipath mitigation —and to the future of middle school girls, who she encourages to stay tough about pursuing a rigorous scientific education.
Experts answer your technical questions about GNSS in this column coordinated by Mark Petovello, University of Calgary.
Opportunities for Using Optical Clocks in GNSS Systems
At its core, the performance of a modern GNSS system depends on the quality of its timing. Galileo’s GIOVE-B satellite is flying the first space-qualified passive hydrogen maser, and active hydrogen masers are part of the ground control segment that will generate Galileo system time. This column discusses the overall timing operation of the current Galileo architecture and points to the possibility of an even more accurate time source for GNSS systems in the future: optical frequency standards.
GNSS data points and factoids to amuse and inform.
Montreal, Québec; U.S. Gulf Coast; the Moon; Worcester, UK; Mumbai; Beijing
A review of Dr. Paul Groves' new book.
Demoz Gebre-Egziabher reviews Paul D. Groves' new book
A review of Jack K. Holmes' new book
Phillip W. Ward reviews Jack K. Holmes' new book
A review of Alan Bensky's new book
Kyle O’Keefe reviews Alan Bensky's new book