May/June 2009

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In addition to positioning, navigation and timing, GPS turns out to be a useful sensor for studies of the Earth’s atmosphere. Synthetically generated, phased-array antennas can process GPS signals to create large antenna apertures. The resulting narrow-beam generation capabilities mitigate interference and jamming and produce high-resolution radar images — which could lead to interesting civil and military applications.

The test signal from SVN49, the latest Block IIR-M GPS satellite, has different characteristics than the operational L5 signal specifications. A group of Ohio University researchers discovered the discrepancies when they tracked the new L5 signal using a commercial antenna and a modified software GPS receiver of their own design.

Leading GNSS researchers present the initial results of their observations of the new (and long-awaited) GPS L5 signal that began transmitting on April 10.

The first of a two-part series that will examine the potential for transmitting GNSS signals in the C-band portion of the radio frequency spectrum. The series will cover C-band services and the effects on a GNSS constellation, space and ground segment, and C-band signal design and user equipment.

Defining who we are by sketching the shadows of strangers is often easier than filling in the outline of our own qualities and aspirations on which to build the basis of mutual interests.

You ask - they answer. Mark Petovello of the University of Calgary finds the experts who can solve your GNSS mysteries, questions, and conundrums.

GPS Surveillance, Backup Blues, GNSS for Africa, Pay to Play in Russia, Indian GNSS, and a Mixed Bag for L5…