Do We Need to Rethink Existing Rules About Satellite Internet Interference?

The rapid buildout of low-Earth-orbit broadband satellite constellations—led by SpaceX’s Starlink—may result in congestion not just in space, but also in wireless spectrum. 

For what could be tens of thousands of satellites to provide usable bandwidth to people a few hundred miles below, policymakers need to be making decisions now about how to manage that spectrum better. One takeaway from an event Tuesday in D.C.,(Opens in a new window) hosted by the think tank New America’s Open Technology Institute: We need to rethink existing rules about interference.

“The satellite spectrum that we assign must remain investment grade,” said FCC Commissioner Geoffrey Starks before warning that inefficient systems and “overconservative assumptions” could make this spectrum less valuable and therefore discourage competition.

Speaking after Starks, his fellow FCC Commissioner Nathan Simington put in a plug for “rules that are tough, sensible, and performance-based.”

The speakers that followed them, including representatives from Starlink and its nascent US rival, Amazon’s Project Kuiper, suggested that part of that could involve relaxing current rules about interference. Instead of relying on radio-frequency models to predict possible interference, the FCC might instead place limits on the observed degradation of other services’ throughput. 

“We think that the degraded-throughput approach is the right approach,” says Julie Zoller, Kuiper’s head of global regulatory affairs. “It sets a standard for a term of permissible interference that’s already used, frankly, by operators coordinating in good faith.” 

David Goldman, SpaceX’s senior director of satellite policy, commented that today’s rules are somewhat inflexible: “It’s a little bit of a coarse metric.”

With 3,224 Starlink satellites already in orbit, per the count(Opens in a new window) maintained by astronomer Jonathan McDowell, and some 700,000 customers who are already seeing slower speeds in the US, SpaceX has much more at stake than Kuiper. That Amazon project recently pushed back its first test launch to early next year and will then need to stage a massive launch campaign to deploy its planned 3,236-satellite constellation.

A performance-focused rule about interference may also require more fault tolerance among existing systems—an apparent lesson learned from the messy rollout of C-band 5G, held up by concerns over possible interference with radar altimeters on airplanes and helicopters.

“We’ve learned a lot about spectrum sharing from terrestrial,” said Harold Feld, SVP at the tech-policy nonprofit Public Knowledge. He counseled it would be worth setting standards for receiver performance, not just that of transmitters—something the FCC is now researching(Opens in a new window).

Goldman’s unflattering characterization of the current regime, in which incumbent hardware is treated as a given: “My system’s really bad, you’d better figure out a way to work around it!”

Whitney Lohmeyer, assistant professor of engineering at Olin College of Engineering(Opens in a new window), said real-time monitoring and coordination of satellite spectrum use, along the lines of what makes CBRS spectrum work on phones alongside incumbent users, should be doable considering that satellite operators already share real-time data about orbital paths of their spacecraft. 

(The issue of orbital congestion only came up in passing, with the FCC’s Starks saying “if we want to sustain space innovation over the long haul, we need to be judicious in how we use our orbits.”)

Although the only other low-Earth-orbit satellite constellation being deployed today is the from UK firm OneWeb, all of the policy types gathered at Tuesday’s event said they expected more competition to arrive.  

That, Feld said, is worth promoting in updated spectrum rules: If relaxing today’s regime allows for more competitors to enter the market, we should take that tradeoff. “From a consumer perspective, having multiple operators is critical,” he said. “Redundancy is a form of resiliency.”