Now that the FCC has issued its national broadband plan, which has as a component a national broadband network for public safety that would operate in the 700 MHz band, it's important to address a crucial misconception, which is that broadband technology can replace mission-critical public-safety voice systems in the near term.

There are two major problems with that belief. First, millions of dollars already have been spent to implement traditional land-mobile public-safety voice systems in this spectrum and many more already are planned. To stop that progress would be disastrous to the public-safety sector and the communities it serves.

Second, and equally important, is that the claims that broadband voice will replace LMR voice in the next two to three years are based on a lack of knowledge of what would be required on a technical level to accomplish this.

The fact is that there currently are no standards being developed — or even planned — to accomplish this feat. The public-safety community has endorsed Long Term Evolution (LTE) as the preferred broadband standard for public-safety data products and the latest version of that standard (Version 8) is strictly a data standard that does not include voice capability. The next version — which is due in late 2010 or early 2011 — is expected to include Voice over Internet Protocol (VoIP) capabilities, but that version will not have any capability to provide one-to-many communications and talk-around (unit-to-unit) voice necessary for mission-critical public-safety communications. LTE is a commercial standard that does not recognize the mission-critical voice communications needs of public safety.

That means that if a first responder cannot reach the network (e.g., a police officer in trouble in a building whose radio cannot reach a repeater), or there is no network, then the radio is useless. That means no communications and a possible life-threatening outcome for the police officer.

It will be many years, if ever, before LMR systems can be replaced entirely by broadband technologies. Before LMR systems could be supplanted, broadband services would first need to be deployed to a level that provides the same extensive coverage that mission-critical voice systems provide, including in-building coverage in many instances. Because coverage area decreases as data rate increases, covering the same area at the same level of reliability with broadband services will require even more sites than the number used today for LMR voice communications.

If LTE developers were to eventually develop standards for mission-critical broadband voice, the public-safety community would need to be involved in the equipment development. Public safety also would need to see it tested and work in the actual public-safety environment on a trial basis before they would be convinced it would be reliable enough to use as an alternative to current LMR narrowband voice systems. System operators and users then would need time to procure and deploy appropriate equipment and devices.

The reality of broadband coverage buildout, standards and equipment development, testing in the public-safety environment, and subsequent procurement means it likely would be 10 to 15 years — or more — before most public-safety entities would be in a position to seriously consider substituting broadband voice for today's LMR mission-critical voice solutions.

What do you think? Tell us in the comment box below.

Harlin McEwen is chairman of the Public Safety Spectrum Trust and chairman of the International Association of Chiefs of Police's communications and technology committee.

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