Qualcomm Inc. is among the companies working on simplfying radio communications for emergency workers with 4G walkie-talkie technology that can operate even if the infrastructure goes down.

The work is part of a larger project to build a nationwide Long Term Evolution (LTE) network in the 700MHz D-Block spectrum for first responders. Emil Olbrich, lead project engineer for the office of law enforcement standards at the National Institute of Standards and Technology, talked about the project at the 4G World show in Chicago last week.

Part of the aim of the work is to reduce the amount of radios that emergency services currently need to support in order to communicate with each other by providing a 4G LTE radio that works nationwide across a 4G network.

For the radios, Qualcomm is "taking the lead" in developing a push-to-talk technology for public safety LTE that can allow communications even if the network goes down, Olbrich says. (See Sandy: The Case for Better Cell Site Backup?)

"In the event that that happens, the public safety radios can be switched so they work like walkie-talkies, talking to each other without the need for infrastructure in between,” he explains.

Regular readers will remember that this kind of radio-to-radio communication was cited as a key public safety application for mesh network vendors back in 2004. Startup MeshNetworks Inc. even won a contract to supply the radio technology for public safety workers in Garland, Texas. (See Mesh Casts Its Net and Commentary: Packet Relay Radio to the Rescue?.)

The meshed systems worked by including routing capabilities in the mobile device so that each radio could act as a node in the network and pass data packets between themselves. It now seems that similar concepts could reappear in the public safety domain as this nationwide LTE project slowly moves forward. (See NY Radio Problems Continue and 9/11: The Radio Issue.)

It is estimated that the network could cost the U.S. government as much as $7 billion all told to build. "Two billion has already been deposited,” says Olbrich.

— Dan Jones, Site Editor, Light Reading Mobile