Using IP to give radio systems a national footprint
Mobile County, Ala., is upgrading its emergency communications with interoperable radios and an IP-based system that brings smart phones into the mix.
The county had an 800 MHz EDACS (Enhanced Digital Access Communications System) for its public safety radio communications, “a technology now sort of outdated,” said Eric Linsley, the county’s director of public safety communications.
The county now is moving to a 700 MHz P25 system from Harris Corp., based on the emerging Project 25 set of standards for interoperable communications. The new system uses Harris’s VIDA (Voice, Interoperability, Data and Access) network, and “that allows us to plug in different Harris services,” Linsley said.
In 2011, Harris approached the county about being a beta tester for a new service called BeOn, a managed group communications tool that enables push-to-talk communications between smart phones and the county’s radio system.
“Who doesn’t want an app like that?” Linsley said. “We just had to provide the phones and the Internet connection.”
More than a year later the county still is using BeOn to give its land mobile radio system a national footprint, enabling users to participate in radio talk groups anywhere they have cellular service.
In addition to expanding a radio system’s footprint, BeOn also can be used to increase capacity by moving some non-critical traffic off of the radio system and onto phones, freeing up space in the RF channels.
Harris began offering the system commercially in August 2012, a year after Mobile County began using it. “I don’t consider it to be beta now,” Linsley said of the project.
But the county has not yet expanded its user base beyond the initial 20 members of the Sheriff’s Department, Fire Department, Emergency Medical Service and the county’s Electronics Department who initially participated in the beta test. Part of the reason is that it currently supports only the Android operating system, although versions for other OSes are in the works. “We’re waiting for the iPhone app,” Linsley said. “That will really kick it off.”
Another reason for its limited use is that BeOn is an extension of current systems, not a replacement.
“It’s good primarily for upper echelon,” Linsley said — that is, department heads and officials who don’t carry radios or who want to remain in touch while travelling out of town. “It’s not to replace your public safety radio.”
Harris agrees with that assessment. It gives users without a radio or outside the radio systems coverage area the option of using a phone instead, but “it’s not an application for a firefighter entering a building or an everyday street cop,” said BeOn product manager David Simon. It relies on cellular phones and carrier systems, with all of their accompanying limitations. If your phone is charged and cellular coverage is good, everything is fine. But if you can’t get a connection or your call is dropped, you’re out of touch.
BeOn provides a link between Harris radio systems and IP networks, including cellular 3G, 4G and LTE networks, WiFi or LANs, enabling push-to-talk, presence and situational awareness through off-the-shelf smart phones. It consists of a server with its own firewall that is linked to the radio backbone on one side and the IP network on the other through an Ethernet port. A mobile app on the phone enables the service.
The server recognizes logical talkgroups established in the digital radio system, which let designated users communicate with each other over managed channels. It also identifies BeOn users who are talkgroup members and pushes transmissions out to their phones. Using a push-to-talk function on the phone, the application receives from and sends transmissions to the server.
The server can handle up to 10,000 users. When a phone is commissioned for BeOn, the application is installed and then configured for access privileges and talk group membership by pushing the settings from a console on the central server.
BeOn is not the only RF-to-IP bridge technology used to expand radio networks.
“There are competing systems out there that are designed as standalone solutions,” Simon said. They work through gateways that can strip out some identity and location data, and they lack the tight integration with Harris’s communications systems. But the tight integration also restricts BeOn’s functionality when used with systems not from Harris and limits its use for establishing interoperable communications across jurisdictional and departmental lines.
BeOn, although commercially available, still is in its early stages of development. It currently supports only voice traffic and is limited to Android devices, although applications are being developed for Windows and iOS devices. Features also are being developed to take advantage of broadband connections with the use of data and images as well as voice. An upcoming release is expected to include location information of users displayed with Google Maps.
“That’s what I’m waiting for,” Linsley said. Currently, the system only tells the user’s distance from the server. “With the maps, we should be able to see where people are. That is cool.”
As a beta user, Mobile County already has contributed to improvements in BeOn, including “a big improvement” in voice quality and in battery life on the cell phones. “The application was reducing the battery life by 50 percent,” Linsley said.
The ability to link with non-Harris systems and older legacy systems also has been improved, and the county has experimented with patching in its legacy EDACS radios, as well as the marine radio channels used by the U.S. Coast Guard.
Despite current limitations, Mobile County responses have been positive.
“Immediately, everybody loved it,” Linsley said. “Right off the bat you are still connected to your public safety radio system wherever you go.”
“The folks using it tend to be the tech folks,” who like to play with apps, however. And during the outbreak of tornadoes in Mobile County on Christmas day, BeOn did not come into play. “Everybody just grabbed their radios.”