Thursday, April 21, 2022


The Next 5G Spectrum Band: 12 GHz for the Win!

By Michael O’Rielly

It should be indisputable that the wireless industry in the U.S. needs access to more mid-band spectrum to compete in today’s modern communications marketplace.  Notwithstanding the substantial benefits that consumers will soon enjoy thanks to the Federal government’s recent actions to reallocate spectrum (like making Phase I of C-Band operational for 5G services), the mid-band spectrum currently available is not nearly enough to support the overwhelming demand for new wireless innovation.  And, the near-term spectrum pipeline is either lacking and/or many years away.  That’s a major reason why I believe it is absolutely imperative that Congress embrace the industry-led proposal to update old allocations to permit 5G use in 500 MHz of the 12 GHz band (12.2-12.7 GHz), while still protecting current incumbent users from harmful interference.  It is not hyperbole to suggest that this would be one the single greatest actions that could be taken this year to ensure the future success of the U.S. wireless industry and improve the lives of Americans.  

Spectrum Policy is Critical

Despite the vital principle of technology neutrality, there are certain inherent advantages to terrestrial wireless communications over its wired counterpart.  While the capacity of wireless networks may not fully equal that of fiber networks, modern wireless services and devices have significant advantages: an untethered connection is both faster and far cheaper to deploy.  Fiber will likely remain a main component of broadband networks – at least for the foreseeable future – but demand for wireless connectivity to support data, voice, and video is driving massive increases in network demand.  As we know, the popularity of mobile wireless services has increased exponentially since its early days.  As 5G America’s President Chris Pearson explained this month, the annual global mobile data growth rate is forty-four percent.  Put another way, mobile wireless network operators could experience a need to “double the size or capacity of their networks every 20 months to keep up with demand.”[i] 

A heavy driver of new wireless capacity needs is broadband traffic.  Sadly, a portion of American families do not yet have access to any broadband connection due to their household location.  Congress has made providing access to these families a national imperative and has allocated almost $100 billion for direct broadband access and another hundreds of billions that could be used for the same.  Wireless broadband solutions will make sense in many of these locations, but adding subscribers to these networks may be further challenged by capacity constraints. 

Unfortunately, achieving the capacity needed to meet growing consumer demand is extremely difficult.  The tried-and-true mechanisms include adopting new equipment and technologies, thereby pushing networks to be more efficient and effective.  But this can only do so much.  Instead, new resources (i.e., wireless spectrum) must be added to providers’ portfolios.  Because spectrum is a finite resource, finding new frequencies for these purposes is like participating in a perpetual automobile accident: few incumbent users are willing to even consider moving out of a band or to allow terrestrial wireless services to be used simultaneously in “their” band.  These spectrum fights have become common place and often demand difficult decisions on which incumbent users must be relocated, displaced, or made to share in order to obtain overall wireless progress.        

The 12 GHz Opportunity

Thankfully, the 12 GHz band provides a welcome opportunity.  While not all incumbent users are on board, a significant number of current licensees, including the primary direct broadcast satellite (DBS) user of the band, are willing to open the band to additional terrestrial wireless services.  This refreshing change represents a path forward, especially with current licensees helping to lead the charge.  And unlike many other bands, there are no government stakeholders in 12 GHz.  Moreover, there appears to be the political will to make the rule changes, even if opposition from some quarters remains, as long as the technical feasibility of potential harmful interference can be successfully documented. 

In simplest terms, the 12 GHz band is currently serving three main purposes and related industries.  First, it is used for downlinks between DBS services and their subscribers.  Second, non-geostationary satellite orbit Fixed Satellite Service (NGSO-FSS, i.e., mainly Starlink) use it to transmit broadband data from its satellites to subscriber receiver dishes.  Lastly, Multi-Channel Video and Data Distribution Service (MVDDS) licensees are allowed to use it to offer a one-way, lower-powered data link service.  Under current rules, both NGSO-FSS and MVDDS licensees in the band must not cause harmful interference to DBS.  In short, the DBS industry has the greatest protections afforded licensees in the band and the most to lose should the interference issue be handled improperly – a point that must be acknowledged as decisions are being made. 

Surmountable Challenges

At this time, the only relevant debate over opening the 12 GHz band should be about the potential harmful interference to incumbent services in the band.  The interference data submitted in the record provides a very favorable picture as it pertains to incumbent NGSOs.  In particular, the RKF Engineering Solutions’ technical report, filed by RS Access last year, studied the co-existence of 5G mobile services and Starlink’s NGSO system in the band.  The extensive and creditable Monte Carlo modeling found that “coexistence between robust deployments of 12 GHz spectrum, both for 5G and for NGSO FSS broadband, is achievable in nearly all deployment scenarios – even without coordination.”  Specifically, the study reported that “few, if any, of the 0.888% of nominally affected Starlink terminals will experience service interruption, or even service degradation, in actual practice for several reasons.”  Ironically, the loudest objector to opening 12 GHz for 5G would face a minuscule risk to harmful interference, according to RKF.  It is also worth noting that Starlink received its spectrum authorizations – which includes 15,000 MHz of other spectrum – without paying a penny.  And, Starlink’s approval for the 12 GHz band and subsequent investment was at its own risk.  In contrast, the current terrestrial MVDDS licensees purchased their licenses at spectrum auctions in 2004 and 2005 and are now asking for an update to outdated rules to support new 5G uses.

While opponents have tried to critique the RKF study, they have offered few compelling arguments and none have submitted expert data of their own to back up their claims.  Remember, the standard is not – and has never been – zero interference; it is harmful interference, which has been managed repeatedly in recent spectrum actions over the last few years (see C-Band, 5.9 GHz, and 6 GHz, etc.).  The D.C. Circuit recently affirmed this standard in a ruling related to the 6 GHz band.  The Court agreed that zero interference is not the standard for spectrum sharing and that statistical Monte Carlo analysis is superior to a worst-case-scenario analysis.

Complaints from some opponents to 5G in 12 GHz should be seen for what they are: attempts at spectrum protectionism.  As mentioned, it’s something faced in almost every spectrum reallocation when bands are not cleared or by services in surrounding areas.  The simple fact is that ceding spectrum – especially if obtained for free like Starlink did – without trying to obtain some type of compensation or understanding might violate its fiduciary obligations to shareholders or management.  The more these entities can raise objections or create a foggy situation, the more likely they can either be paid or push the issue for another day, in which it might get paid.  That, however, should not be a winning strategy, and it is certainly not a strategy that helps American consumers.        

Further, sound spectrum policy decisions cannot be made based on arguments presented by those seeking to block competition.  This can come in many forms, and somewhat depends on what new services are allowed into the band.  But make no mistake, a select portion of existing licensees often raise unfounded concerns and even challenges to additional band uses that ultimately could be used by consumers for substitute product lines or services.  The prospect of competing with innovative new wireless services makes existing providers do questionable things, even if the goal is to delay new service introduction by months or a few years.  In today’s vibrant broadband marketplace, a little delay can be all that is needed to gain an advantage or stifle new entrants.            

Lack of Reasonable Alternative Bands

Opening the 12 GHz band to 5G can be justified in its own right, but an examination of other potential options should add further justification for the case.  It is simply the best mid-band option available for future wireless services.  In other words, there is not a long list of viable mid-band spectrum that can or should be used in the alternative.  In fact, the list is short and quite dubious.  After a likely protracted process, exactly how much licensed spectrum should be expected from the 3.1 to 3.45 band, and how soon?  It’s hard to see that process concluding sooner than 2025 or without a completely mixed bag of encumbered blocks making sharing regimes or unlicensed regimes more likely.  Other bands that have been bandied about by experts – like 7, 8, 13-15 GHz – all come with substantial issues or are years away, at best.  It’s entirely feasible that another 100 MHz could come from the residual satellite use of C-band, but good luck unlocking it, given the way satellite providers were treated by the previous reallocation and the actions of the FAA with regards to the altimeter debacle.  It is hard to see any other momentum or movement on mid-band spectrum, other than 12 GHz.  Should anyone believe that this Administration wants to go an entire four years without identifying and making a new mid-band spectrum allocation?

Additionally, the wireless industry, both licensed and unlicensed, has made it clear that when it comes to 5G and higher spectrum bands, they need large blocks.  Specifically, they have sought blocks of 100 MHz or those that are easily interchangeable to assemble into a functioning whole.  Almost all of the alternative bands being discussed in spectrum circles are unlikely to meet this condition.  While I am certainly hopeful that the Department of Defense will open 3.1-3.45 to permit licensed, sharing, and unlicensed in sufficiently large units, I am somehow doubtful that it will under the current statutory restrictions.  That’s where the 500 MHz of 12 GHz comes in: it can provide exactly what is needed today.  Depending on construction of the band plan, it should be possible to configure in a way to ensure wide blocks for 5G services.

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The 12 GHz band represents an amazingly rare win-win spectrum opportunity for consumers, the wireless industry, and our telecom leaders.  New 5G services in this band are necessary for future wireless competitiveness, and, based on the expert engineering, can be done without unduly impeding incumbent uses. 


The opinions expressed in this blog are those of the author and are not intended to be a submission to the Federal Communications Commission with the intent to influence agency employees in the performance of their official duties in any current or future Commission matter.

 

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