RealTime IT News

Rosum Puts TV in a New Light

Rosum is putting the old TV transmission towers that dot high hills around major cities to a new use.

The system is designed to use television towers as a form of GPS to broadcast a signal to a person's cell phone to help locate them.

It was designed to help emergency responders locate victims of disasters, such as the collapse of the World Trade Center towers or Hurricane Katrina.

Satellite signals are not the strongest, as anyone who has tried to use a cell phone in an elevator knows.

And GPS  signals are designed for tracking in open, outdoor areas, but the reliability drops greatly once indoors, or in an urban jungle like a city with tall buildings. Satellite radio is even worse.

By contrast, television signals were designed for indoor reception. Television signals are "loud, powerful and low frequency," Jon Metzler, Rosum Corporation's director of business development, told internetnews.com.

This means signals are blasted out with megawatts of power at very low frequencies which helps them through walls. They come in horizontally, off the horizon, instead of beamed down like a satellite transmission.

Also, there's a good amount of redundancy in urban areas, meaning the same channel comes from multiple transmitters. Plus, as Metzler said, it's already built and ready to use.

Rosum already offers a location service in San Francisco, New York and Washington, D.C., and coverage has only been in those cities. This expanded system will provide coverage from Boston all the way to the nation's capital.

Rosum's system for locating people via cell phone does have a few weak links.

It relies on the targets to have their phones on them, and in order to send out a signal where the person is located, the cell phone's own network is used.

However, it's not tied to a cell phone, so it could also be a Wi-Fi notebook or other wireless device.

In addition to the search and rescue of individuals, the system is also a viable means of vehicle tracking.

"Vehicles had used GPS, but in urban canyon settings like skyscrapers it didn't work. That's where the need is most glaring. The folks who need real-time position location and suffer the most for the absence of it are public safety," said Metzler.

Good luck, said Ken Dulaney, vice president of mobile computing research for Gartner.

"Getting another system into handsets is a very complicated process. They have to get device manufacturers to include this, and that isn't easy when device prices and margins are falling," he said.

"Probably a good idea conceptually, but the devil is in the implementation. While promised for years, location services have been a big disappointment," he added.

"The problem has not been the technology, but the interfaces to other systems which are different for every operator."

Rosum's other new technology, to be introduced at the CTIA conference this week in Los Angeles, is what it calls Reliable 9-1-1.

Telephony using Voice over IP (VoIP) technology does not support 911 emergency calls, a glaring hole in the service that is becoming an issue as more people shift to Vonage, Skype and other services.

Some service providers have tried to add their own system, such as AOL and Level 3.

Vonage added its service via Verizon last year after SBC refused Vonage's overtures.

Rosum's system will be sold to telephony firms so they don't have to build their own, said Metzler.

Metzler will introduce the Reliable 9-1-1 system at the E9-1-1 Summit taking place as a part of CTIA.