We Read the Unclassified Spectrum Sharing Report So You Don’t Have To
The Emerging Mid-Band Radar Spectrum Sharing (EMBRSS) Feasibility Assessment Report is comprised of 231 pages of information that will inform the implementation of the White House’s National Spectrum Strategy. Spectrum for the Future had previously called for the report’s public release, and we’re grateful that the federal government recently released a partially-redacted, unclassified version of the report for public consumption.
In short, the EMBRSS report says dynamic spectrum sharing in the lower 3 GHz band – NOT clearing for exclusive licensing – is “the only potential means to maximize availability of spectrum for commercial operations” with mitigation techniques in place.
The EMBRSS report speaks to the promise of dynamic spectrum sharing as the solution to maximizing scarce spectrum resources. Here are the key takeaways:
New commercial use of the 3.1-3.45 GHz band is possible through the development of enhanced dynamic spectrum sharing capabilities
The EMBRSS report suggests that opening the 3.1-3.45 GHz band to licensed sharing between federal and commercial users is possible so long as certain conditions are met – primarily ensuring DoD systems can maintain their readiness to meet any challenge or threat at home or abroad. For example, the Secretary of Defense would need to determine “that sharing those frequencies with non-Federal users would not impact the primary mission of military spectrum users in the covered band.” Other conditions include building upon the “field-proven model” of the Citizens Broadband Radio Service (CBRS), addressing cybersecurity concerns, and establishing proper interference safeguards.
Clearing the Department of Defense (DoD) from the 3.1-3.45 GHz band – which would be necessary to make exclusively licensed commercial use possible – is not a viable option as it would result in significant and long-term impacts on US security.
The report states that “proposals for DoD to vacate the [3.1-3.45 GHz] band may result in setting the DoD back several decades compared to near peer adversary nations, take decades, and result in significant financial cost, up to hundreds of billions of dollars.” The EMBRRS report supports findings in a recent study by the Brattle Group, which also offered unique insights into the economic advantages of spectrum sharing in the lower 3 GHz band compared to relocation or compression. While legacy wireless carriers continue to beat the drum on a “spectrum pipeline” that would require clearing or compressing DoD in the lower 3 GHz band, the EMBRSS report confirms that such an approach is not a realistic solution.
Dynamic spectrum sharing that builds on the success of the CBRS band is a promising opportunity for creating new commercial wireless opportunities in the lower 3 GHz band.
DoD uses the 3.1-3.45 GHz spectrum band for “critical homeland defense and other operational missions,” operating hundreds of systems in the band in the U.S. and around the world. Since relocating or further compressing these mission-critical systems is not realistic, dynamic spectrum sharing technology offers the best path forward for opening the band to commercial use to meet the nation’s wireless needs. While this will be an engineering challenge akin to the “moonshot” of the 1960s, the EMBRSS report states that a Dynamic Spectrum Management System (DSMS) provides “the only potential means to maximize availability of spectrum for commercial operations when government systems are not active in the band.” DoD leaders have reinforced the same point in recent weeks.
The CBRS model offers a strong blueprint for implementing dynamic spectrum sharing in spectrum bands where federal incumbent systems are present.
CBRS is a successful model for dynamic spectrum sharing and commercial access in bands where federal incumbent users exist. The EMBRSS report recognizes this fact, clearly stating that “the CBRS sharing framework can be evolved and scaled to meet DoD mission requirements,” with the expectation being that a sharing framework will offer flexibility to users and employ advanced interference mitigation techniques.
Spectrum sharing benefits the nation and all stakeholders, including DoD, and rigorous testing will help refine the findings of the report.
The EMBRSS report provides a long list of lab and field testing and measurements that can be executed to further advance the prospect of implementing dynamic spectrum sharing in the lower 3 GHz band. As we enter the implementation phase of the National Spectrum Strategy, government resources should be devoted to expediting these tests in order to move us closer to effectively deploying dynamic spectrum sharing technologies, not on studies that confirm what we already know about costly, time-consuming, and unfeasible relocation and compression.