FCC seeks comments on 700 MHz narrowbanding

Whether the current Dec. 31, 2016, deadline for public-safety 700 MHz narrowband systems to migrate from 12.5 kHz channels to 6.25 kHz-equivalent channels should remain in place is one of the key questions that the FCC is asking in a proceeding launched this week.

On Monday, the FCC’s public safety and homeland security bureau issued a report and order, as well as a notice of proposed rulemaking (NPRM) regarding rules for the 700 MHz narrowband spectrum allocated to public safety. Several public-safety entities previously asked the FCC for waiver extensions — many until 2024 — to allow them to use their existing 700 MHz narrowband systems for 10-15 years and/or to better determine what options they may have in the long-term future, especially if mission-critical voice over broadband LTE can be developed.

“In light of these developments, we seek comment on whether the long-term future of the700 MHz narrowband spectrum band would be best served by suspending or eliminating mandatory migration to 6.25 kilohertz technology,” the NPRM states.

“Could the spectral efficiency benefits of narrowbanding be outweighed by the potential inefficiency of requiring public-safety agencies to devote resources in this band to a technological path that may not meet their long-term needs? Conversely, do the benefits derived from enhanced efficiencies of narrowband technology outweigh the costs of maintaining the current framework in the interim?”

In addition, the FCC seeks input regarding whether the interim Dec. 31, 2014, deadline — after which vendors could no longer market, manufacture or import gear that is unable to operate on 6.25 kHz channels — should be delayed or eliminated.

Ralph Haller, chairman of the National Public Safety Telecommunications Council (NPSTC), said that he has not yet read the FCC document closely, but he expressed support for the agency taking action.

“I’m glad that the commission has finally teed these things up, and there’s an opportunity now for people to provide their input,” Haller said during an interview with Urgent Communications. “That’s certainly a step in the right direction.”

In addition to the NPRM, the FCC issued a report and order that outlines technical requirements for the 700 MHz narrowband spectrum, addressing issues such as adjacent channel power limits.