Start-up on track to fill gaps in GPS

Even if you’re lost, Rosum will find you. That’s the promise of the Redwood City start-up that has figured out how to use television signals to track your whereabouts.

Rosum’s technology complements the satellite-based global positioning system. The decades-old GPS, originally built for military purposes, can get a fix on gadgets equipped with GPS receivers — as long as you’re out in the open. But GPS doesn’t work well in skyscraper-filled urban canyons and it doesn’t work at all inside buildings.

But TV signals penetrate through buildings, and Rosum uses them to track people where GPS can’t. The first device using Rosum’s technology is in the prototype stage. Navigation products using it will make their debut next year, according to Rosum Chief Executive Skip Speaks.

“There are immense black holes in the GPS system, and we can fill the gap,” says John Metzler, Rosum’s director of business development.

By Dean Takahashi

Mercury News

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