If There is No More Beachfront, Users Have to Share the Beach: the Argument for Flexible Spectrum Sharing

Spectrum valuable for the same reason beachfront property is valuable: "they aren't making any more of it."

In other words, if mobile and untethered spectrum demand grows by 1,000 times over the next decade, as many assume it will, there is precious little unallocated spectrum that can be put to use.

Indeed, there is growing recognition in the U.S. communications policy community that the big potential gain in useful communications spectrum will have to come from more efficient use of spectrum already allocated, but under used.

Though in principle it might be possible to move existing licensees from their current frequencies to new spectrum, the cost to do so generally is quite high, and the time to make the changes generally long.

So there is new thinking about ways to share existing spectrum, without the need to move existing users. There also is new thinking about how to manage interference in a decentralized and efficient way, without relying on slow, cumbersome, expensive adjudication by FCC rule makings.

“Today’s great spectrum policy challenge is thus to maximize the value that can be derived from bands already in use,” say the authors of Unlocking Spectrum Value through Improved  Allocation, Assignment, and Adjudication of  Spectrum Rights, written by Pierre de Vries, Silicon Flatirons Center senior fellow and co-director of the Spectrum Policy Initiative, and Philip Weiser, University of Colorado Law School dean.

And, as a practical matter, there is no way to do so efficiently is to create a new framework for the decentralized management of spectrum, the authors argue.

The authors suggest “command and control” regulation of communications spectrum be replaced by a system allowing spectrum users to directly negotiate coexistence and spectrum agreements without government regulators having to act as gatekeepers.

New ways to manage potential interference and then adjudicate interference disputes would be part of the framework, largely because “a lack of clarity concerning interference

prevention between neighboring spectrum users and an inadequate system for allowing trades and resolving disputes between users” are primary reasons why spectrum is inefficiently used.

Claims of harmful interference between systems are at the heart of disputes about whether a user’s rights have been violated, or, alternatively, whether a user has lived up to its responsibilities to tolerate reasonable levels of interference, the authors note.

So any decentralized, fast-acting system would require clear methods to identify when harmful interference (not simply some interference) has occurred, and a mechanism for judging whether such claims have merit, and addressing the claims.

The three-part plan would create “harm thresholds” that are clear, allowing devices and users to tolerate some amount of interference, but also specify clear signal level impairments that create the basis for action against an infringing party.

In other words, there would be some mutually agreed upon interference that does not compromise a licensed holders rights and ability to use spectrum. Under that threshold, a license holder would not have sufficient cause for action against another party sharing spectrum.

The rationale there is that not all interference is debilitating, and much time and expense would be removed if all parties knew exactly what the limits were.

But the harm claim thresholds also would specify what in-band and out-of-band interfering signal levels would trigger a claim of harmful interference, and the ability to seek a remedy.

A second requirement is to create a more-liquid market by allowing licensees to negotiate efficiently with holders of neighboring blocks of spectrum. Right now the process of creating operating rights between spectrum neighbors is cumbersome, expensive, politically charged and slow.

A second challenge for spectrum regulation is to overcome the collective action problem that stems from band fragmentation.

At present, it is cumbersome and expensive for licensees to negotiate with spectrum holders in neighboring spectrum bands to deal with potential interference issues. One reason is that the FCC and National Telecommunications and Information Administration are required to handle any such conflicts.

Such disputes would be resolved faster, at less cost, if the parties could efficiently negotiate with each other.

The third element is creation of an adjudication mechanism capable of acting faster than the FCC now can act, without the need to rely on “rule making” processes.

The proposal would allow more-flexible clearing of spectrum for shared use, including both

exclusive, tradable and flexible use licenses assigned by auction (mobile services, typically) and open access or “unlicensed” regimes that allow unlicensed flexible use.