By Donny Jackson
Enterprise Wireless Alliance (EWA) this week asked the FCC to consider measures to help private land-mobile-radio (PLMR) operators with T-Band spectrum (470-512 MHz) systems subject to “harmful interference” from television broadcasters that were repacked in the band seven years ago.
EWA President and CEO Robin Cohen requested the FCC established a task force to consider the matter in a letter to FCC Chairwoman Jessica Rosenworcel, noting that a previously successful spectrum-sharing arrangement was “irrevocably altered” in a manner that has resulted in problems for PLMR system in five metropolitan markets.
“Historically, the FCC has required later-authorized systems to resolve interference with earlier-granted licensees,” according to the EWA letter signed by Cohen. “It has not done so in this instance, and the efforts of the PLMR licensees to induce voluntary interference protection from the identified DTV stations have not proven effective.
“The result is the loss of allocated PLMR spectrum in New York, Miami, Chicago, Houston, and Dallas—five of the major, most spectrum-congested markets in the nation—due to interference from DTV stations whose principal communities of service are well outside those markets.”
This week’s EWA letter to the FCC about interference in the T-Band spectrum swath follows previous correspondence with the agency on the issue dating back to 2020. In addition, the Land Mobile Communications Council (LMCC)—now the National Wireless Communications Council (NWCC)—formed a task force to explore the problem and offered recommendations in 2021.
EWA Chief Strategy Officer Mark Crosby said the FCC has not responded to any of these communications to date.
“We’re not trying to be a pain in the neck,” Crosby said during an interview with IWCE’s Urgent Communications. “But it would be nice to have an answer to our request for assistance.”
Crosby said that there have been examples of broadcasters and PLMR operators being able to resolve interference concerns on their own. However, that has not been the case for some operators in the five metropolitan areas mentioned in the letter; in fact, one PLMR operator “spent several hundred thousand dollars” on new spectrum and other work to keep its system operational.
In her letter to the FCC, EWA’s Cohen stated that PLMR networks operating on T-Band spectrum have long experienced some interference at particular times, but the issues since 2017 have been more consistent.
“The systems have not been immune from interference in the past, including seasonal ducting problems from more distant co-channel television stations,” according to the EWA letter. “That type of intermittent interference is troublesome but temporary and is a reality of congested airwaves.
“This situation is different. Rather than having a problem on a few days during periods when the seasons change, this interference is so strong that it takes the PLMR systems off the air and is occurring for many hours several days a week or even multiple consecutive days.”
Of course, the T-Band airwaves—used to support LMR system in only in 11 spectrum-hungry metropolitan areas of the US—have been the subject of considerable debate since Congress passed an omnibus spending bill that was enacted in February 2012.
That legislation created the FirstNet Authority and called for 20 MHz of 700 MHz spectrum to be licensed to the new organization charged with building and maintaining a nationwide public-safety broadband network (NPSBN). In addition, it included language requiring the FCC to begin taking steps to auction public-safety T-Band spectrum in 2021. That auction mandate was nixed in December 2020 as part of another massive spending bill, much of which was designed to provide COVID-19 relief.
Public-safety representatives had opposed the auction of the T-Band spectrum from the day Congress passed the 2012 law, noting that T-Band airwaves are used by more than 900 public-safety agencies to support LMR networks in 11 of the largest U.S. metropolitan markets.
The Government Accountability Office (GAO) also released a report that there was no adequate spectrum to relocate LMR systems in Boston, Chicago, Los Angeles, New York and Philadelphia.
