Quarterscope converts Wi-Fi cards plus a wardriving database into a virtual GPS receiver: A few weeks ago, Wi-Fi Networking News talked to Ted Morgan, the founder and president of Quarterscope, a company which had just won an award at the cellular industry's big trade show for location services, finishing behind well-established Ekahau. Quarterscope's product is software that uses a database of wardriving records that it matches against the signals received by a Wi-Fi radio to produce an approximate set of coordinates, like a virtual GPS.

"What got us started down this path is the density of public and private hot spots," Morgan said. "No one realizes just how many of these access points has been installed. They see the sales numbers, but they don't extrapolate the fact that people are going home and plugging them in."

Morgan said that they have primed the pump of their database using existing information from research groups, hobby wardrivers, and collective databases. "We're aggregating from lots of different existing sources today," he said.

Wardriving uses "stumbling" software like NetStumbler to record all of the network names and unique access point hardware addresses at regular time slices, like every second, combining that information with GPS (Global Positioning Satellite) receiver coordinates tied into the same laptop or handheld.

Quarterscope is starting its own stumbling efforts by installing wardriving devices on vehicles in metropolitan areas that drive random paths, such as delivery vans. "If you have somebody who is scanning for a full day, in metro areas, they can scan over 5,000 a day, particularly in downtown areas," Morgan said.

Oddly, he said, certain kinds of vehicles don't work because they drive similar routes every day, such as police cars. "if you really look at what a cop does all day, it's pretty revealing."

Morgan said that they've had legal advice as to whether passively scanning or pinging for a beacon violates any laws int he U.S. "We've gotten consultation on the whole process, and it’s very clearly within legal bounds," he said. "If we have any concerns, it's more on a perception side of things. You can go to the FBI Web site and they very clearly state that passive scanning is fine. The problem is if you connect into somebody’s network."

Quarterscope's software generates a virtual serial port on a Windows system, and uses the NMEA GPS protocol. it works with a variety of mapping programs that support GPS receivers, such as Microsoft Streets.

The granularity of the data which Quarterscope uses to produce coordinates is quite fine. "Every single access point tends to have hundreds of readings behind it which are showing different positions and signal strengths. It's very difficult to use just a couple of readings and develop a position," Morgan said.

The company may use its data to drive market research analysis, because they believe they might wind up with a more accurate eye-level view of deployment of access points by vendor and location. He noted that he can derive vendors from the access point's unique hardware address; these addressees are assigned in ranges to companies.

Quarterscope has seen what Morgan characterizes as a surprisingly high level of interest from cell phone makers and cell carriers. These companies are concerned about relying entirely on GPS, especially in urban areas where downtown caverns block accurate satellite reception, or inside buildings or other structures where Wi-Fi might be prevalent and GPS unavailable.

Morgan said that when a carrier tries to sell a GPS-enabled phone, the first thing a customer does is try it out in the store--where it fails because it can't get a satellite read.

Morgan expects that Quarterscope will resell its software as a consumer offering, but its primary market will be to OEMs, or manufacturers that will repackage or recombine the software.

Manhattan remains one of Quarterscope's great points of interest because, Morgan said, in some areas their stumbling software can see well over 25 access points at once. The next most dense city, Boston, might reach a maximum of 15 in similar areas.

"We talked to the carriers, and they all refer to Manhattan, because it also happens to be where GPS struggles as well," he said.