Pentagon starts search for spectrum sharing tech in lower 3GHzPentagon starts search for spectrum sharing tech in lower 3GHz

The US Department of Defense (DoD) is now officially looking for spectrum sharing technologies that could allow military users to operate in the lower 3GHz band alongside commercial wireless providers.

"The goal of this effort is to show how advancements in one or more of the key spectrum-sharing enablers can achieve the overall objective of proving the viability of spectrum sharing in the 3100-3450MHz band," according to the DoD's new posting on Sam.gov.

Sam.gov – System for Award Management – serves as the US government's central database for registering as a federal contractor, managing entity information and finding federal business opportunities. It's basically the platform that companies can use to apply for federal grants and contracts.

The Pentagon is specifically looking for companies and technologies that can "develop and mature spectrum access technologies to enable improved cognizance of spectrum activity, protection of US activity in the electromagnetic spectrum domain, and the ability to coexist and/or share spectrum anytime, anywhere access is needed."

The posting comes roughly six months after the top US military officials hosted an event focused on spectrum sharing. They described the technology as a "moonshot" that would help the US maintain an advantage against its rivals both economically and militarily.

However, it's not clear how the DoD's spectrum-sharing efforts will fare under the second Trump administration. As Light Reading previously reported, there is a pretty good chance that incoming President Donald Trump will wrest control of a portion of the lower 3GHz band away from the US military and allocate it to the 5G industry for commercial use. That could potentially obviate the need for any kind of sharing technology.

The debate

Spectrum sharing remains a hot topic in the US wireless industry. That's because big 5G network operators like AT&T and Verizon do not want to share their spectrum with anyone else, including the Pentagon. Instead, they prefer to use exclusive spectrum licenses, where they're the only entity authorized to use them. That's the kind of spectrum they've built their networks on.

But the US military is loath to release spectrum it has been using for decades. Indeed, some Pentagon officials estimate it will cost more than $100 billion to move existing military radar systems off the lower 3GHz band. That would be necessary to do before commercial 5G operators could access the band.

It's also not clear how much money an FCC auction of lower 3GHz spectrum might generate among 5G players – or whether those revenues could be used to relocate US military radar operations to another band.

Regardless, DoD officials for years have been clear that they support sharing paradigms rather than spectrum relocation efforts.

"This report ... concludes that shared Federal and non-Federal use of the 3100-3450MHz band for shared Federal and non-Federal use is feasible if, and only if, the listed conditions enumerated in Section 8.4 of this report are fully proven through rigorous, in-depth, real-world full scope operational testing with Joint Force assets and implemented in advance of any auction," according to the DoD's Emerging Mid-Band Radar Spectrum Sharing (EMBRSS) feasibility assessment, released earlier this year. The report considered sharing in the lower 3GHz band in very specific ways that would protect existing military operations.

The players

It's worth noting that the US military isn't the only proponent of spectrum sharing. Comcast, Federated Wireless, Digital Global Systems (DGS) and others have voiced support for sharing scenarios. Broadly, they argue that rising demands for spectrum – stretching from the Wi-Fi industry to the drone industry to the auto industry – naturally will create constraints on a limited resource that only sharing can alleviate.

Indeed, a form of sharing has already been deployed in the 3.5GHz CBRS band. But that kind of sharing is considered relatively manual and basic, and the DoD is hoping to develop a more advanced form of sharing.

Also lurking within the spectrum sharing debate is a battle between the cellular industry and the cable industry. Broadly, some companies in the US cable industry are working to prevent 5G providers from obtaining more spectrum in the lower 3GHz band. Their goal is to halt the expansion of fixed wireless access (FWA) services across the US.

"Instead of innovating to meet the new competitive challenge they face, cable is trying to block policies that stimulate investment and competition," wrote Nick Ludlum, a top official with the CTIA, which is the main trade association for wireless network operators like AT&T, Verizon and T-Mobile.