Rivada Networks has received patent approval for its peer-to-peer method of determining the location of mobile devices that does not rely on GPS-based or network-based location technology.

Rivada Networks’ latest patent describes technology that lets nearby mobile devices triangulate off one another, “taking advantage of modern devices' accelerometers and other means to determine relative location and movement, independent of the availability of a device's main network,” according to a company press release.

Clint Smith, Rivada Networks’ chief technology officer (CTO), is an active firefighter who said he developed the technology in an effort to provide more location information in a fireground scenario that didn’t rely on GPS—a satellite technology that does not work well in buildings—or traditional network-based triangulation, which often requires additional network infrastructure that may not be available.

“This was done to try to improve situational awareness for our incident commander,” Smith said during an interview with IWCE’s Urgent Communications. “The Holy Grail is trying to find where your interior search team, your interior host team or your fireground team are and where all the people are, especially in a night situation or during a chaotic event, because you lose track of where people are, no matter how good you are—things happen.”

Instead of trying to deliver absolute locations (such as XY coordinates) of personnel and other assets to the incident commander, Smith took a page from submarine-location technology to devise a method that would provide the relative locations of a handset based on a known fixed point—in this case, the fire truck.

“I was thinking that, when you start from the truck, where the incident commander is, that’s the center focus,” Smith said. “It doesn’t matter what the lat-long coordinates really are for that location. What the incident commander needs to know is: Is he 50 feet in front of me and 20 feet up? That’s what he needs to know, not [XY coordinates].

“We ping each one of the handsets, so we know what distance is between each of the handsets, and they basically try to position against each other. So they know how high they are, what their altitude could be and they known their distance, so they’ve got their vector information. And, once you have your vector information with two sources or three, you can determine your position.”

The Rivada patent leverages features that already exist in current commercial handsets, including accelerometers and sensors that estimate the handset’s altitude based on barometric pressure, Smith said.

“When you start putting all of these little pieces together that haven’t really been available to us, your positional location capabilities start increasing greatly—at least the potential is there,” he said.