Every three months or so, the FCC’s 700 MHz Interoperability Docket finds its way into the Washington media.  Given the recent announcement of both new and interim FCC Chairpersons and their coming agendas, I expect the issue to continue to get coverage, so let’s recap the issue and status in that proceeding.

When the FCC created the lower 700 MHz Band Plan, it placed mobile broadband A, B and C Block spectrum adjacent to spectrum used for broadcast television, most significantly, Channel 51 stations.  This created substantial interference issues (as well as build out issues due to exclusion zones created around Channel 51 license areas), particularly for A Block license holders, due to the presence of high powered broadcast signals in nearby spectrum.

At auction, markets being what they are, those disadvantages impacted the value of the A Block spectrum, which was sold at a significant discount to other available spectrum.  While many regional and smaller competitors purchased A Block licenses, AT&T avoided the A Block and instead purchased licenses at auction and in the secondary market in the B and C bands.  Almost immediately after the auction ended, however, the purchasers of the A Block licenses began arguing that any handset used by AT&T to receive B or C Block signals should also be capable of operating on the A Block as well, making all of the spectrum bands “interoperable” – thus the name for our proceeding.  Those carriers asserted that handset manufacturers would never make devices just for them, and that the only way they would be able to obtain the latest and greatest technology would be if they could piggy-back on AT&T’s supposedly greater purchasing power.

As we have explained in this space before, however, there is no credible evidence to support those assertions.  Indeed, US Cellular has deployed in the A Block and has brought a number of devices to market in that band including the latest, greatest “must-have” products like Samsung Galaxy S4.

But there is an even larger problem with their argument; the thorny issue of interference.  AT&T did not bid on A Block spectrum at auction specifically because of the interference issues posed by Channel 51 broadcasters and others.   AT&T has conducted rigorous testing and engineering analyses, and those tests and analyses make very clear that at typical real-world power levels, Channel 51 transmissions would substantially degrade our LTE service – creating LTE “no call” zones – if AT&T were required to use chipsets that enabled A Block reception.  In other words, we have spent billions of capital dollars deploying the best LTE network in the world, which would be significantly degraded and less efficient if “interoperability” were mandated by the FCC without addressing these interference issues first.

Fortunately, there is a solution to the interference problems on the horizon.  As a result of the incentive auction legislation passed last year, the FCC is empowered to conduct two auctions that, if successful, will enable willing broadcasters to surrender spectrum currently devoted to broadcast television.  The first swath of broadcast spectrum cleared post-auction is the aforementioned Channel 51 spectrum which will once and for all resolve the Channel 51-related interference issues (as well as the exclusion zones that prohibit mobile broadband build-out in some areas).  That auction could occur as early as next year.  To be clear, there would still be other interference issues that would need to be resolved – in particular, those related to the approved power levels with respect to the E Block spectrum.  But the FCC has the power to harmonize those power transmission levels to resolve those additional interference issues.  So, we are relatively close in time to a real solution to this problem.

What’s more, as part of our acquisition of Qualcomm’s D Block spectrum (where we also voluntarily agreed to harmonize the power limits of that spectrum to ease additional interference issues), we made the commitment to support interoperability no more than two years after all of these interference issues are resolved subject to caveats on supply-side device availability.  Our full commitment is here.

Interference, however, remains a real issue today.  And we don’t have to look any further back than the Lightsquared  situation to understand the problems caused by not fully addressing interference issues before we move ahead with policies that negatively impact existing consumer services and devices.  Unlike Lightsquared though, here we have a path forward that can create a win-win for all consumers of mobile broadband services — more spectrum capable of delivering lightning fast mobile broadband and continued global leadership in LTE infrastructure.  Hopefully policymakers will take the path towards problem solving here.

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