Page:The 5G Ecosystem Risks & Opportunities for DoD.pdf/5

 multiple systems into a broader network while sharing information in real time, improving communication across Services, geographies, and domains while developing a common picture of the battlefield to improve situational awareness. This improved connectivity may in turn enable a host of new technologies and missions, from hypersonics and hypersonic defense to resilient satellite constellations and mesh networks.

Spectrum will play a key role in the operation, development and roll-out of 5G. Peak data rates are driven by the amount of spectrum that is available to a wireless service. In 4G, up to five 20 MHz channels can be bonded together. But in 5G, up to five 100 MHz channels can be bonded together, enabling speeds approximately 20x faster than 4G and 4G LTE. While some 5G technology will be deployed in the currently-used cellular spectrum and achieve modest gains in performance (LTE is already fairly well optimized), full 5G development will require significantly more spectrum to provide another step-change improvement in performance for consumers, DoD or otherwise.

Countries are pursuing two separate approaches to deploy hundreds of MHz of new spectrum for 5G. The first focuses on the part of the electromagnetic (EM) spectrum below 6 GHz (“Low- to Mid-Band Spectrum,” also referred to as “sub-6”), primarily in the 3 and 4 GHz bands. The second approach focuses on the part of the spectrum between ~24 and 300 GHz (“High-Band Spectrum,” or “mmWave”), and is the approach taken by the United States, South Korea, and Japan (although all three countries are also exploring sub-6 to various degrees). U.S. carriers are primarily focused on mmWave deployment for 5G because most of the 3 and 4 GHz spectrum being used by the rest of the world for 5G are exclusive Federal bands in the United States, extensively used by DoD in particular. The question of spectrum allocation is at the heart of the 5G competition, for the spectrum band of choice, whether sub-6 or mmWave, impacts nearly every other aspect of 5G development. Spectrum bands in the 3 and 4 Ghz range dominate global 5G activity because of improved propagation (range) over mmWave spectrum, resulting in far fewer base stations needed to be deployed to deliver the same coverage and performance. Because large swaths of the sub-6 bands in the United States are not available for civil/commercial use, U.S. carriers and the FCC (which controls civil spectrum in the US) are betting on mmWave spectrum as the core domestic 5G approach.

U.S. carriers may continue to pursue mmWave, but it is impossible to lead in the 5G field without followers. Leadership in wireless networks requires the global market to subscribe to DIB 5G Study