The FCC’s rules require systems that use public-safety 700 MHz narrowband spectrum — all portions of the band, with the exception of the 32 dedicated interoperability channel pairs — to operate in 6.25 kHz-wide channels, or the equivalent, by Jan. 1, 2017. New licensees were given a Jan. 1, 2015, deadline.

These transition dates and rules were established by the commission’s National Coordination Committee (NCC), which was convened in 1999 to develop the rules for 24 MHz of narrowband and wideband public-safety spectrum at 764–776/794–806 MHz. The NCC recognized that the high power TV channels (63, 64, 68 and 69) in operation at the time would encumber the use of the public safety spectrum in these bands until the digital television transition was complete, which at the time was scheduled for Jan. 1, 2007.

Given the advent of Project 25 Phase 2, which is based on a two-slot, time division multiple access (TDMA) solution, the NCC believed that the 10 years between the DTV transition date and the FCC’s 700 MHz narrowbanding deadline was ample time for licensees to execute the migration. While the Phase 2 standard still is not entirely completed, a large number of P25 Phase 2 interfaces have been finalized.

However, the DTV transition was not completed until June 14, 2009, and 700 MHz spectrum became widely available to public safety nationwide in the same month. (By this time, public safety’s 700 MHz spectrum no longer consisted of 12 MHz of wideband and 12 MHz of narrowband spectrum, but rather 12 MHz of narrowband spectrum and 12 MHz of broadband/guard band spectrum, due to a band reconfiguration in 2008.)

While 700 MHz fixed and mobile equipment has been available to public safety since before the DTV transition was complete, TDMA-capable equipment only recently has become prevalent in the sector. Consequently, agencies that purchased 700 MHz equipment as recently as 2009 may not be able to utilize that equipment in conjunction with TDMA-based equipment, which will further complicate the task of meeting the FCC’s 2017 deadline.

It is important to consider that while a few areas of the country have implemented 700 MHz systems that operate at 6.25 KHz efficiency, many areas do not have capacity needs that necessitate such operation. This creates a situation where adhering to the FCC’s 700 MHz narrowbanding rules that exist today may require the premature replacement of equipment in areas that have not identified the need for such efficiencies and are able to meet their spectrum needs while operating at 12.5 kHz bandwidths. Many of these areas did not have full access to 700 MHz spectrum on Jan. 1, 2007, and subsequently were not afforded the 10-year migration window outlined in the FCC’s rules.

On March 21, 2012, several public-safety agencies and cooperatives in Arizona filed a petition for rulemaking with the FCC to address this situation. The basis for the petition is that while certain agencies within Arizona effectively utilize 700 MHz spectrum today throughout the region, the commission’s rule would require the premature replacement of current subscriber units and fixed infrastructure to meet efficiencies in an area that has yet to identify the need for such efficiencies. While the petition outlines in detail the financial and logistical impact of this requirement and suggests that the deadline be pushed back until Regional Planning Committee 3 determines that a real need for 6.25 kHz efficiency exists in Arizona, this complicated issue has yet another element that needs to be considered.

Over the last several years, while public safety has sought sufficient spectrum to meet its future broadband needs, the FCC has sought comment regarding whether 700 MHz narrowband spectrum could be utilized in a flexible manner to support those needs. Those in public safety know that the mission-critical voice derived from 700 MHZ narrowband systems will be necessary in many areas across the country for many years until broadband technologies can provide this capability. “Flexibility” implies that 700 MHz narrowband spectrum could be used in either narrowband or broadband configurations. This must be accomplished in a coordinated fashion to ensure that both methods of implementation can work effectively.

As public safety’s use of broadband spectrum for video, data and mission-critical voice applications advances in the coming years, and as flexible use of 700 MHz narrowband spectrum in support of broadband applications in certain geographic areas develops, an interesting question emerges: Should public-safety agencies today be required to adhere to the 700 MHz narrowband efficiencies developed in 2001 in areas where such efficiencies are not needed?

In light of recent events associated with additional 700 MHz broadband spectrum being dedicated to public safety and the creation of the National Public Safety Broadband Network, it is fair to state that the public safety landscape has changed and current rules, developed a decade ago to promote efficient use of public safety’s 700 MHz spectrum — when there was a limited number of ways to do so — need to be revisited. Today there are multiple technologies, and thereby multiple methods, of achieving more-efficient use of public safety’s 700 MHz spectrum.

Public-safety communications will be transitioning from a voice-dominated field to a multi-dimensional environment where mission-critical applications and capabilities never before envisioned will be a reality, and where spectrum will be utilized in a manner that is very from how it was used in the past. As we move forward to a time when these advanced public-safety broadband features and capabilities prosper, regulatory bodies need to re-evaluate current rules and deadlines that were developed in an age of public safety communications when voice was king. They also need to ensure that policies reflect the new dynamic of public-safety solutions, which will include broadband applications that leverage commercial off-the-shelf (COTS) technologies.

Meanwhile, public-safety leaders need to expand their perspectives and work with the regulatory community to ensure that any legacy rules still in place that may be burdensome to public-safety agencies are revisited as the sector travels down the path to an exciting broadband-centric future.

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

Stephen Devine is the chairperson of the National Regional Planning Council and chairperson of the Region 24 700 and 800 MHz Regional Planning Committee. He can be reached at 573-522-2382 or stephen.devine@dps.mo.gov.

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