If your department has not made the switch from using 25 kHz efficiency technology to using at least 12.5 kHz efficiency technology, your department is now on the Federal Communications Commission radar screen.
Effective Jan. 1, departments are in violation of the FCC's rules for narrowbanding and face potential enforcement actions that may include admonishment, monetary fines or loss of license.
The Jan. 1 deadline was the culmination of the FCC's efforts — efforts that began in 1992 — to ensure more efficient use of the spectrum and greater spectrum access for public safety and non-public safety users. Originally referred to as "refarming," the migration to 12.5 kHz efficiency technology, or narrowbanding, was designed to create additional channel capacity within the same VHF and UHF radio spectrums, and support more users.
The migration included all public safety and business/industrial land mobile radio (LMR) systems operating in the 150-512 MHz radio bands. Those organizations must cease operating using 25 kHz efficiency technology, and begin operating using at least 12.5 kHz efficiency technology.
A deadline missed
The FCC is serious about its deadline. Those licensees facing unique circumstances may request waivers, but waiver requests must meet a high standard and the FCC does not routinely grant such waivers. If your department has not complied with the narrowbanding regulations, you should contact the FCC's Bureau of Enforcement immediately and prior to filing any waiver request.
FCC interference rules will not protect non-compliant wideband systems from harmful interference after Jan. 1. Those systems that failed to narrowband by the deadline could create interference or interoperability problems for systems that have complied with the FCC regulations. Finally, non-compliant wideband equipment will not be available after Jan. 1.
What is narrowbanding?
Narrowbanding is designed to ensure more efficient use of the VHF and UHF spectrum by requiring all VHF and UHF public safety and industrial/business land mobile radio (LMR) systems to migrate to at least 12.5 kHz efficiency technology.
More specifically, all existing Part 90 radio systems operating in the 150-174 MHz and 421-512 MHz bands had until that deadline to convert those systems either to a maximum bandwidth of 12.5 kHz or to a technology that provides at least one voice path per 12.5 kHz of bandwidth or equivalent efficiency.
Heretofore, the majority of UHF and VHF LMR licensees have operated using 25 kHz efficiency technology. However, the UHF and VHF frequency bands have become congested with limited spectrum available for system expansion or implementation of new systems. The migration to 12.5 kHz efficiency technology requires that licensees operate more efficiently, either on narrower channel bandwidths or increased voice paths on existing channels. This will allow creation of additional channels within the same spectrum, thereby supporting more users.
Don't get taken
LMR system vendors may misunderstand the FCC's rules or misrepresent them in an effort to sell equipment. What appears to be a bargain may actually be a rip-off if what you are purchasing is single-mode 25 kHz equipment that is now obsolete.
Be particularly careful in the purchase of used equipment — this is not a case of "one man's junk is another man’s treasure." You do not want to be funding someone else's narrowband conversion. The more familiar you are with the FCC's requirements, the less likely that a vendor or other unscrupulous party will be able to take advantage of you.
Narrowbanding rules provide for eventual migration from 12.5 kHz to 6.25 kHz bandwidth as a measure to further increase efficiency and channel availability. The FCC expects that licensees ultimately will implement equipment that is designed to operate on channel bandwidths of 6.25 kHz or less. The FCC has not set a deadline for 6.25 kHz implementation and no deadline will be established without further notice and comment.
Organizations may narrowband to 6.25 kHz voluntarily. Keep in mind that all 150-174 MHz and 421-512 MHz equipment certified after Jan. 1 must include the ability to migrate to 6.25 kHz capability.