Space Ops: Battle Brewing For Scarce Mid-Band Spectrum

Congress is reopening a Pandora’s Box of spectrum allocation as it weighs opening up certain frequencies that have historically been exclusively used by the U.S. military to wireless networks.

In recent hearings in the House and Senate, lawmakers aimed to bring a fresh focus to the longtime debate, two years after the FCC’s spectrum authority expired for the first time in 30 years, and as multiple countries have launched 5G networks in the midrange spectrum that the U.S. has not made available to its own commercial sector.

The hearings set the scene for what may be a lengthy debate about how to maintain U.S. leadership in 5G and 6G technology amid competition with China, while ensuring defense capabilities, from electromagnetic warfare to missile defense, remain unencumbered.

Sen. Ted Cruz (R-Texas), chairman of the Senate Committee on Commerce, Science, and Transportation, introduced the Spectrum Pipeline Act in 2024 to restore the FCC’s authority to auction off 1250 MHz of licensed spectrum for mobile broadband services. If enacted, the bill will cover the band of frequencies between 1.3 GHz and 13.2 GHz.

Much of the U.S. military’s critical radar systems operate in the 3.1-3.5 GHz spectrum band–also referred to as the “lower-3” portion of the S-band–and the X-band, which sits in the 8-12 GHz range. Systems like the Aegis Combat System and the Patriot Missile System rely heavily on those radars to track and target potential threats.

Proponents of spectrum reallocation claim that the U.S. could recoup as much as $100 billion from new auctions, and help its commercial sector build advanced networks to compete globally with Beijing’s Huawei.

But the Pentagon is pushing back. Department of Defense officials have said for years that the DOD requires full use of the spectrum to properly conduct operations.

This is not a new claim. In 2020, telecom firm Ligado invested heavily to expand its land-based 5G network via L-band spectrum used by military GPS receivers. While the FCC approved the plans, the Defense Department ultimately blocked it via a lengthy campaign warning against potential interference with its GPS receivers. Ligado filed for bankruptcy in January.

Military leaders continue to assert their need to control all of the allocated spectrum.

U.S. Air Force Gen. Gregory Guillot, commander of U.S. Northern Command and the North American Aerospace Defense Command, told the Senate Armed Services Committee on Feb.13 that operators required “uninterrupted and complete access to the entire spectrum” to properly use the full range of threat tracking sensors.

As the Defense Department plans to field a new multilayered missile defense shield–first called “Iron Dome,” now renamed “Golden Dome”—that exclusive spectrum use becomes even more critical, he said.

Experts told Congress that it is possible for a new missile defense shield to operate alongside commercial 5G networks, while others warned that the impact of reallocating spectrum away from DOD uses must be approached with caution.

Cruz, for his part, expressed skepticism of the Defense Department’s claims during a Feb. 19 hearing of the Senate Committee on Commerce, Science and Transportation.

He noted that the DOD is operating in the Indo-Pacific region by using the same midrange spectrum that countries like Taiwan, Japan and South Korea are employing for commercial purposes.

“If DOD is technically unable to operate alongside wireless carriers using these bands domestically, how on Earth could we expect to prevail in a Pacific conflict?” he said. “It simply is not credible.”

The Pentagon will ultimately need to leverage commercial innovation in space to prevail over its adversaries, Matt Pearl, director of the strategic technologies program for the Center for Strategic and International Studies, said during the Feb. 19 hearing.

Wireless networks will be “critical” in the race to harness artificial intelligence-enabled capabilities, he noted. “This won’t happen unless we make commercial spectrum available.”

Lawmakers for now appear interested in exploring technologies that can enable “dynamic spectrum-sharing,” for example using modeling and simulation techniques to show how best to divvy up some of the most desired midrange bands and indeed, the whole spectrum. They also propose a thorough assessment of the 7 and 8 Ghz bands to see what may be auctioned off to industry without harming national security.

The debate over civil and military spectrum allocation is not new. But as pressure mounts on the U.S. to build advanced wireless networks and global military competition heats up, expect the drumbeats on both sides to grow ever louder.