FCC commissioners yesterday unanimously adopted a notice of proposed rulemaking (NPRM) that would require 700 MHz public-safety broadband networks throughout the U.S. use LTE as the common air interface.

“As a general rule, the FCC is not in the business of picking standards or picking technology platforms, but this is a widely agreed-upon exception to that rule to ensure nationwide interoperability for public-safety communications,” FCC Chairman Julius Genachowski said during the meeting. “There’s widespread agreement that this step needs to be taken.”

In fact, the agency’s support for LTE for public-safety broadband had been evidenced at the staff level for almost a year and was included in guidelines the FCC gave in the fall to the initial 21 entities that were granted waivers for early 700 MHz mobile broadband network deployments. The NPRM would make the LTE standard applicable throughout the nation.

Such action is needed to avoid the “balkanization” that historically has occurred between public-safety voice networks that have followed myriad standards paths, Commissioner Michael Copps said. Copps noted that many of the interoperability issues cited during the 9/11 attacks almost 10 years ago still exist.

“I suppose you could make the argument that, in some ways, we are marginally better off now than we were then,” he said. “But we are nowhere — and I mean nowhere — close to implementing an interoperable broadband public-safety system in this country that our people deserve and require.”

Public comments on the interoperability framework are being sought in several areas, including the architecture of the systems, security and encryption requirement and roaming between networks. Commissioner Robert McDowell said he is glad the FCC is seeking comment on the manner in which future technological platforms would fit into this interoperability platform.

In addition, McDowell reiterated his position that flexible use of the 700 MHz narrowband spectrum be examined, so those frequencies can be used to support broadband networks in the future. McDowell also said he believes the FCC should pursue a auction of the 700 MHz D Block spectrum, which public-safety officials have been lobbying Capitol Hill and the White House to reallocated for first-responder broadband uses.

“In a perfect world, with the 10th anniversary of 9/11 fast approaching, we would have already finalized an order setting forth auction and service rules for the D Block spectrum,” McDowell said. “Perhaps we would have already concluded an auction of this spectrum, and public safety entities would be in a position to elect to partner with these auction winners. I am eager to move to this step, which I urge that we undertake sooner rather than later.”