November/December 2007

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Satellite signals propagating through the Earth’s atmosphere can be profoundly affected when the Sun acts up, but a U.S. federal agency now offers help for users to minimize the effects on their GNSS-dependent activities.

Interest has surged as wireless carriers and mobile handset manufacturers have adopted GPS technology. But how do carriers and end users know that their A-GPS products will work?

Over the past 10 years, GNSS reference networks have simplified and extended the range of high-precision positioning over longer distances with the aid of differential corrections. However, a number of operational and environmental factors continue to limit the full realization of these techniques’ potential. Access to and use of additional satellite signals from multiple GNSS systems could help address these limitations. This column examines the potential benefit of GPS + Galileo positioning under a variety of ionospheric conditions.

How will the Open Service Galileo signal in space change the acquisition process in GNSS receivers? What  factors affect the acquisition of weak GNSS signals and what can be done to alleviate them?

Technology agnostic. Now there's an interesting term. . . it has such a fine post-Enlightenment ring to it, connoting an analytical, studied approach to things. But when it comes to space-based positioning, navigation, and timing (PNT), I'm not one. I'm a GNSS believer. I'm for it. I'm a big fan.

An inventor and technology transfer expert, her trademark is taking an inexpensive device and finding a new use for it that raises the bar for accuracy in navigation

Ethiopia; Iceland; Copenhagen; Moscow; Easter Island