​Narrow Band Explanation and Impact

IL-APCO PowerPoint Presentation on Narrowbanding

Yahoo Group for Illinois Narrowband Issues

Much awaited narrowbanding mandate was released 12-23-2004 by FCC

Executive Summary of the Order:

FCC establishes January 1, 2013 deadline for migration to 12.5 KHz technology

  • Applications for wideband operations (25 KHz channels) will be accepted until January 1, 2011
  • Application for modification of operations that expand the authorized contour of an existing station using 25 KHz channels will be accepted until January 1, 2011 (also applies to "new" systems submitted for licensing)
  • Manufacture and importation of any equipment on 25 KHz channel will be permitted until January 1, 2011
  • Part 90 paging-only frequencies are exempt from this ruling

PROMOTION OF SPECTRUM EFFICIENT TECHNOLOGIES ON CERTAIN PART 90 FREQUENCIES.   Addressed eighteen petitions for reconsideration of the rules adopted in the Second Report and Order proceeding to promote migration to narrowband (12.5 KHZ) technology in the private land mobile radio (PLMR) services. (Dkt No.  99-87). Action by:  By the Commission:

Adopted:  12/20/2004 by MO&O. (FCC No. 04-292).  WTB

Misc Narrowband/Refarming Information:

NPRM Reconsideration FCC Response (12-23-04)
FCC issues Stay of Narrowband Implementation Date
Link to Comments Filed with the FCC re: 99-87
APCO/NPSTC Files Request for Stay of Implementation Date ( 8/29/03 )
APCO Files Request for Reconsideration with the FCC ( August 18, 2003 PDF)
Narrowband Recon APCO Call for Support Document (PDF)
Final Rules per Federal Register ( July 17, 2003 )
Narrow Band FCC Notice 03-34  
FCC Narrowband Update from Illinois Association of Fire Districts June 24, 2004
International Association of Fire Chiefs comment on December 12, 2003
Federal Register 7/17/2003: Narrowband rules finalized! Impact starts January 2004

The January 2004 deadline pushed back

Related APCO Letter (must read)

PSWN goes on record: New rule will negatively impact legacy wide-band interoperability channels such as IFERN, IREACH, ISPERN, and MERCI

NTIA's Petition for Reconsideration

What others are saying about the narrowband rules

Narrowband Background:

All two-way radios use a radio channel that has a particular size, called bandwidth. In the past, all radio channels were 25 kHz wide. Any older radio, designed to work on a 25 kHz channel, will now be referred to as "wideband."

As far back as 1992, the FCC began a process known as "refarming". One of the goals of refarming was to create more radio channels to meet the needs of two-way radio users. In short, the FCC decided to create "new" radio channels that were one-half the size of the older ones. Changing the channel size effectively makes twice as many radio channels. As a result, the new two-way radio channels will now be 12.5 kHz in size and known as "narrowband."


Quite often, in an effort to explain refarming in layman's terms, it was stated that "It's like taking a four-lane superhighway and narrowing each lane to get eight lanes total." This sounds good - doubling the available lanes, or in this case, radio channels. Except that if you fail to also narrow the cars and trucks, the vehicles will be sideswiping each other, or at the very least, striking mirrors - a layman's explanation of "interference!" If some vehicles are narrow, and some wide, the highway will be chaotic - just as the radio interference will be chaotic if the change is not coordinated.  

As the process of refarming moved along, the FCC created mandates for the two-way radio equipment manufacturers. In 1997, all new two-way radio models had to be capable of operation on the new 12.5 kHz narrowband channels. This is often called "dual-mode" equipment since the radio can accommodate both narrow- and wide-band channels. The idea was to begin to move toward narrowband channel operation over time. At that time, the FCC did not create any mandates to remove older wideband radio units from service or require you to use a new narrowband channel.

FCC Actions, Narrowband Mandates:

On February 25, 2003 the FCC released updated "narrowband" mandates. These actions are designed to phase in narrowband (12.5 kHz) and phase out older wideband (25 kHz) channels over the next 10 years. The process consists of 4 main mandates. A final set of rules were posted in the Federal Register on July 17th, 2003. FCC Rule in PDF format.

Mandate 1)

All existing wideband (older) radios may continue to operate until January 1, 2013. Public Safety has until January 1, 2018. After that date, two-way radios must operate completely on the new "narrowband" (12.5 kHz) channels.

Mandate 2)

Two-way radio manufacturers cannot manufacture, import or sell any models of wideband (25 kHz) equipment after January 1, 2008.

Mandate 3)

Manufacturers who submit any new two-way radio models for FCC certification after January 1, 2005 may not offer new radios that contain the ability to operate on older wideband (25 kHz) channels. This means no more "dual-mode" radios - they will ONLY work in narrow-band mode and NOT be compatible with existing wide-band systems.

Mandate 4)

After January 17, 2004, FCC license applications for new radio systems will not be accepted for older wideband (25 kHz) channels. This portion of the Rule, despite the Petitions for Reconsideration, has been stayed as of December 3, 2003. In addition, limitations will be placed upon modifications to any existing wideband FCC licenses. This may be up to interpretation by a frequency coordinator, but any new system, or an existing system that expands it's service area or relocates a base station may be required to move the entire system to narrowband - a costly proposition.

Summary of the Mandates:

Starting January 17, 2004, you may not license any new two-way radio systems in the older wideband mode. You will be limited in making any changes to your existing wideband license. In fact, the coordinators will likely ask that applications be submitted in October-November of 2003 in order to process the license. After 2005, the radio manufacturers must begin to eliminate older wideband mode from any new models of two-way radio. After 2008, you will not be able to purchase any new two-way radio equipment that will operate in the wideband mode. In 2018 you will have to take all older wideband equipment out of service.

How This Affects Your Agency:

For now, all older two-way radio systems will continue to operate as they have in the past. Short term, do not let your existing FCC license expire under any circumstances. If you should receive anything in the mail concerning your FCC license, contact IMSA or APCO  immediately for assistance. You may also contact a Co-Chair of the MABAS-IL TCD Committee listed on the Communications & Dispatchers contact us page. You do not want to lose your current wideband license.

Over the next year, it would be prudent to evaluate how many older wideband two-way radio units you have in service. These older units will need to be phased out over time. Some of your newest two-way radios are likely to be "narrowband ready" right now because they are "dual-mode".

Over the next 5 years, updating your older two-way radio units, a few at a time, will put you in the best position to be "narrowband" ready for the future.

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