January/February 2009

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The massive turnover that occcurs when the United States executive branch moves from the hands one political party to another will see the departure of many officials with GPS expertise. Who will fill the gap and what will that mean for the nation’s premier space-based positioning, navigation, and timing program?

Clashing trajectories pressure GNSS providers - but growing commercial markets inspire a search for compatibility at the third plenary meeting of the International Committee on GNSS.

A new technique for computing protection levels in “liability critical” applications — those in which large undetected GNSS position errors can have severe legal or economic consequences.

The IMES positioning and communications system developed as part of Japan’s Quasi-Zenith Satellite System may be the perfect answer for “seamless” ubiquitous positioning — or perhaps a jamming threat to the integrity of GPS.

So, President Obama wants to spend some money on infrastructure, eh? Well, here’s an idea: send some of it GPS’s way.

The idea of flying two or more satellites in controlled formations with complementary sensors on board to execute scientific research missions will receive a lot of practical attention in the near future. In some cases, GNSS signals will be used to meet the high-precision positioning and orientation requirements for this application. Other, higher-orbit missions will employ RF-based techniques similar to those used to make GNSS carrier phase measurements. The second and final part of the series describes the technologies and techniques used in this scientific research.

Sibling Rivalry at ICG, Gas Tax Wars in Oregon, What Next in Washington D.C., and The Gift of the Magi