FCC eases interim deadlines for 150-174 MHz/421-512 MHz operations; January 1, 2013 final deadline for migration to 12.5 kHz operation still in effect

Years ago the Commission ordered that industrial and public safety land mobile stations in the 150-174 and 421-512 MHz bands get on the narrowband bandwagon: abandon the longstanding 25 kHz bandwidth operation and convert to gear capable of more spectrum-efficient 12.5 kHz (and, ultimately, 6.25 kHz) operation. Ever striving for more efficiency, the FCC noted that a shift to 12.5 kHz operation would, in theory, double the number of available channels; shifting to 6.25 kHz would double it again, resulting in four channels in place of each 25 kHz channel. 

The timeline for the transition was last set in 2004 with a series of deadlines, some kicking in on January 1, 2011 – which seemed to afford plenty of time for the conversion. But in 2009 the public safety land mobile community expressed concern that the transition to narrowband could disrupt their operations. In response, the FCC has now adjusted some of its interim deadlines. Importantly, the Commission did not alter the January 1, 2013, deadline for all systems to convert to narrowband operation.

Today’s land mobile technology, at least in the bands up to 512 MHz, no longer requires the 25 kHz channel bandwidth that these radios have used for several decades.  The problem is that all radios communicating with one another must be using the same bandwidth. Those old 25 kHz radios, which splash their signal across four 6.25 kHz channels, will become obsolete on January 1, 2013; yet many of these radios remain serviceable.  Land mobile operators, particularly public safety licensees, do not want to have to scrap equipment prematurely to comply with narrowband regulations.  They also do not want to be precluded from expanding their existing systems without having to replace all their radios. 

One looming deadline would have stopped the manufacture of any 25 kHz capable radios – even dual bandwidth models – after December 31, 2010.  Licensees who need to replace some of their radios but don’t want to do a full system conversion are squirming.  Here is what the FCC did to cut them some slack:

  • The January 1, 2011, deadline for stopping manufacture or importation of 25 kHz-capable radios will remain but will be waived until January 1, 2013 – but only for existing models that have previously been certified by the FCC.  No new 25 kHz-capable models will be certified after December 31, 2010, even if they are also capable of narrower bandwidths. 
  • No new radio systems using a 25 kHz bandwidth will be licensed after December 31, 2010, and existing systems may no longer expand their service area, except through case-by-case waivers, which may be difficult to get, although the filing of some requests is virtually certain.  New or expanded systems without a waiver will be licensed only for bandwidths of 12.5 kHz or less.
  • The requirement to include 6.25 kHz capability in new radios will be deferred until January 1, 2013, in light of the fact that technical standards are still being finalized.

So the FCC is marching forward with compulsory narrowbanding, with a final deadline of January 1, 2013 still in place – but only down to 12.5 kHz, with 6.25 kHz narrowbanding being pushed off a bit until it becomes a more practical.