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Rethinking Part 90 Spectrum Assignment Policies

December 19, 2016

Rethinking Part 90 Spectrum Assignment Policies

At the recent IWCE Critical LTE Communications Forum in Chicago, part of our panel discussion was the impact of having a device available to police and firefighters with far more capabilities than push-to-talk.  While all agreed that having such capabilities would be useful, a concern was expressed about making devices too complicated (as well as expensive) for first responders in the heat of the moment.

An audience member queried us as to whether millennials, already comfortable with technology that us older folks had to learn, would more easily be able to utilize more complicated devices, even in the heat of battle.  It was a fair point, whether the “aging out” of us analog folks meant more opportunities for digital.  How this will play out in the FirstNet roll-out remains to be seen, as well as what PTT functions will ultimately remain available.

This same issue can now be seen in the traditional land mobile world.  We have a large number of land mobile radio people who run public safety radio systems who are retiring.  It is rare that I deal with the same radio guy at the beginning of 800 MHz rebanding deals and at the end.  For some Regional Planning Committees (RPC), this has created an increasing strain as fewer and fewer knowledgeable volunteers are being asked to do more and more work.  On the commercial side, there are many traditional two-way radio folks who took their Nextel money and are happy in retirement, changing the shape of two-way radio shops.

This generational change has created the need for educational programs for people entering the field.  For example, IWCE has offered Land Mobile 101 and Radio for IP Professional style courses for several years.  When we created the Government Wireless Technology & Communications Association (GWTCA), we made sure that we included a top flight educational institution on our Board.   Now that we (almost) live in a post-narrowbanding, post-rebanding land mobile world, perhaps now would be a good time to revisit some of our land mobile radio traditions and methodologies that we are teaching to these new folks.

For example, the original radio service allocations were created many decades ago.  There have been changes over time.  The twenty Part 90 service categories were consolidated into two broad pools in the 1990s.  The 2010s brought the final stages of narrowbanding, freeing up interstitial channels for full power use.  These changes were hard fought at the time, with many in opposition.  I remember when we were promoting a concept to consolidate Part 90 into three service pools, and one counsel for a coordinator told me, “[t]he FCC doesn’t have the $@%*s to consolidate the pools.”  But he was wrong.  The changes happened, and users benefitted.

The most significant change from that time is that the introduction of digital modulation technologies on shared VHF and UHF channels.  This has created the requirement for channel monitoring different than the traditional “listen before talk” for the user.  Concomitant with channel monitoring changes, there is a push towards eliminating shared channels amongst users, instead trying to create exclusive channels, in order to enable more digital units in the environment.  On the other hand, the introduction of automatic interference avoidance devices may allow for even more sharing, although this type of sharing is different than what we’ve experienced through the decades, where the device does the listening automatically, and not the user of the device.

Exclusive channels and collision avoidance systems do not require the same level of concern about what users are talking about, and how much airtime they are using, as compared to shared analog voice channels.  Rather, the assignment methodology is more science-based.

These changes make for an important time and opportunity for reviewing our old assumptions and methodologies.  Leveraging new technologies for spectrum analysis and reviewing the process of spectrum allocations between Business and Public Safety in the various bands should be issues on the review table.  For example, back in 2004, we filed a Petition for Rule Making on behalf of Icom America, Inc., asking the Commission to reallocate then scantly used Part 22 paired VHF channels to public safety.  While the Petition received little public safety support at the time, these channels could have served as a springboard towards a long term realigning of the Part 90 VHF non-paired channels into paired configurations.  Perhaps there are opportunities with new technologies to accomplish the same goals.

Similarly, it would seem an appropriate time to re-review the channel allocation methodology.  The current frequency coordination system was created in the 1980s, when we had twenty different radio services.  At the time, with one coordinator per service, it was imperative that the committee be representative of the users of the service.  In an analog, listen before talk world, knowledge of the types of voice communications on that shared channel was imperative, and this was one way to ensure it.

The concept of a single coordinator per service went away with service consolidation, meaning that some committees have smaller representativeness within their categories than before.  And outsourcing means that most frequency coordination has been consolidated into a few outside companies.  We should take the opportunity to conduct a comprehensive review of these rules and practices, and see if other services provide examples of best practices that could be used to amend Part 90.

We should leverage the “new blood” and “new science” available to us, and re-examine how we’ve been doing business, and see if we can do it better.


Alan S. Tilles

Georgina L.O. Feigen