Cheap GPS

S5: GPS Made Cheap

Posted by samc on December 17th, 2007

The Associated Press reports that a Utah company, S5 Wireless, has a small, cheap GPS tracker that can be powered by a single battery for up two years. Unlike the Global Positioning System, S5’s technology tracks indoors and out, but only works where the company has a network of stations to receive S5 signals at 900MHz.

Billionaire Craig McCaw is the venture’s main backery. He founded one of the country’s first cell-phone companies, and WiMAX provider Clearwire. S5 plans to start building 900MHz receiving sites in some major U.S. cities next year with coverage in 35 cities expected within three years.

The company invisions, an S5 chip in dog collars, complete with a battery, in a package about the size of a stick of gum that costs $3 to $4 to make. When the battery runs down, you buy a new collar.

The chips act like a GPS in reverse. GPS receivers need a line of sight to the sky, so they work only outdoors, and are fairly power-hungry.

By contrast, the S5 chips send radio signals out to receivers mounted on cell towers. By measuring the difference in the time the signal takes to arrive at three different receivers, S5 can compute the location of the sender to within about 30 feet outdoors, or 45 feet indoors. The same principle can be used for locating some cell phones in an emergency but is much less accurate. LoJack equipment also sends radio signals from a stolen car, but it uses a lot of power and is expensive compared to S5’s chips.

“There’s a lot of activity, a lot of companies, and of course a lot of venture capital which is being made available for those kinds of initiatives,” says Dominique Bonte, who covers GPS technologies for ABI Research. “There is a big belief that whoever comes up with something that’s cheap, that works and is available will hit the jackpot there.”

To gain a foothold, S5 will give away the designs for its chips, letting anyone make their own or incorporate the functions into existing chips, like those in cell phones. It plans to make money by charging for the location service, though at low rates, around $1 a month, Carter said.

As a bonus, S5 chips could transmit small amounts of data generated by other devices. For instance, a diabetes patient’s glucose meter could be monitored remotely.

To pinpoint a chip’s location, S5 needs three receivers within the signal’s range, about a mile in cities, Carter said. The company plans to cover “several” major cities next year and 35 cities within three years. S5 plans to use free, unlicensed spectrum in the 900 megahertz band. Steve Chacko, S5’s director of product marketing, likened the feat of picking up those signals from miles away to extracting a needle from a haystack. But he said sophisticated low-power radio technology makes S5’s plan viable.

Meanwhile, WiFi chipset maker Atheros plans to buy GPS specialist u-Nav Microelectronics for $54 million. The chipmaker says it plans to incorporate GPS on its chipsets and reduce the cost of adding location services. Atheros plans to integrate u-Nav GPS into its “Radio-on-Chip for Mobile” product line.

source : dailywireless.org