On Friday the FCC unanimously voted to create the Citizens Broadband Radio Service in the 3.5 GHz Band. This action will create a 150-megahertz band suitable for wireless broadband, including 100 megahertz previously unavailable for commercial use because it was earmarked for military radars. The Commission adopted a comprehensive framework encompassing three tiers of shared use (Incumbents, Priority Access, and General Authorized Access), coordinated through one or more Spectrum Access Systems. Today we released the rules for this new “innovation band”, which will become effective when they are soon published in the Federal Register.
The new 3.5GHz rules will provide tangible benefits for all Americans. First, the new rules will support important national defense missions by protecting incumbent radar systems from interference. Second, the new rules will further increase the speed, capacity, and adaptability of wireless networks, leading to better mobile Internet performance for everyone. Finally, we expect to see wide deployment of wireless broadband in industrial applications – advanced manufacturing, energy, healthcare, etc. – supporting innovation and growth throughout our economy.
While spectrum management can be a complex undertaking, drawing from engineering, economic, and legal analysis, the basic goal is simple. The Communications Act calls for clear rules so that myriad uses of radio technology will not cause “harmful interference” to one another. Just as most cities have zoning boards to accommodate different, often incompatible, forms of land use, so does the FCC (along with NTIA, our counterpart in the executive branch overseeing federal spectrum uses) create zoning rules for radio spectrum. These zoning designations are called “allocations” and, within allocations, we authorize different “radio services”.
Over time, the FCC has worked to make these categories more flexible, to accommodate a range of different uses and technologies. This flexibility is important. It allows wireless users, whether licensed or unlicensed, to upgrade from one generation of technology to the next without asking permission from the regulator, which is still required in some other countries. It is no accident that technologies like Wi-Fi and 4G cellular quickly took root in the United States.
Yet, despite this push for greater flexibility, certain assumptions about our spectrum management framework have remained fixed. These assumptions reflect hard distinctions – bright lines – embedded deep within the regulatory framework. Some of these assumptions are technological. In an age of high-powered analog transmissions, it made sense to put different radio uses on different bands, everywhere in the United States. Others result from legal and institutional choices made decades ago.
While the categories have served important purposes over the years, the division of the radio spectrum into different tranches – for different kinds of users and uses – can also limit flexibility and efficiency. As evidence, one need only look at the innumerable exceptions, footnotes, or other asterisks that have been added to the rules over the years to accommodate uses that do not fit within neat regulatory boxes.
With the new 3.5 GHz rules, the Commission enables a new model that uses modern technologies – spectrum sensing, cloud computing, and others – to break down some of the old categories. A few examples:
- Federal vs. Non-Federal Allocation. Most spectrum bands have a primary allocation to federal uses (overseen by NTIA) or non-Federal uses (overseen by the FCC). Even where there are overlapping “co-primary” allocations, in most cases one of the two kinds of users is clearly the predominant user in the band. More recently, as in the 5 GHz band, advanced sharing has taken root. We continue this trend in 3.5 GHz, where commercial broadband users will share with several different types of military radar systems.
- Licensed vs. Unlicensed Authorization. Our nation has benefited from enormous innovation and investment in both licensed and unlicensed wireless systems. 3.5 GHz represents the first time we will enable a spectrum band to “behave” in a licensed or effectively unlicensed manner depending on an economic mechanism. In general, the band will be available for anyone to use without expecting interference protection (similar to unlicensed). However, where demand to access the spectrum exceeds supply, we will hold auctions for geographically targeted, short-term “priority access licenses”, which will provide interference protections in portions of the band.
- Carrier vs. Private Networks. While we strive to create “flexible use” rules, in practice the attributes of different bands tends to skew the use to either carrier networks (those that support consumer service) or private networks (those that support the individual needs of a business or industry). As a consequence, private networks and carrier networks cannot share the same equipment, in some cases raising costs and slowing innovation. Because of the granular licensing in 3.5 GHz, we expect that carrier and private networks will be able to share the same band, on a widespread basis, and will benefit from equipment that may be used for either purpose across the band.
It will take some time to see the results of this new approach. We still have several steps ahead of us before the band will “turn on”. For example, we will need to authorize Spectrum Access System providers and establish auction procedures for the new priority access licenses. We expect multi-stakeholder groups to agree on procedures for coordinating use in the band. And, as with any new spectrum band, technology vendors will have to design equipment that meets the technical requirements spelled out in the rules. We also will continue to consider options for a small set of decisions not finalized in the Report and Order.
With the basic regulatory framework now in place, however, we now have a solid foundation to move forward. We are excited to see how the future develops in the 3.5 GHz innovation band.