Satellite transmission power battle drags on after WRC-23

International regulators have left the door open to relaxing a cap on satellite transmission power in non-geostationary orbit as soon as 2027, NGSO operators say, even as their geostationary peers assert any change has been blocked until at least four years later.

A proposal to review Equivalent Power Flux Density (EPFD) limits affecting how strong NGSO signals should be to avoid disrupting satellites in geosynchronous orbit (GSO) was one of the most divisive issues at WRC-23, a quadrennial event for updating global spectrum rules that wrapped up Dec. 15 in Dubai.

After weeks of intense treaty-level talks that pitted NGSO newcomers seeking greater power and capacity against more established GSO players concerned about increased interference, a compromise was reached: Technical EPFD studies can advance without regulatory consequences.

For some, this means regulatory proposals for updating EPFD limits cannot be put up for debate until the next time the United Nations’ International Telecommunication Union holds a WRC (World Radiocommunication Conference), in 2031.

However, SpaceX and the Alliance for Satellite Broadband, a group Amazon created to lobby for updating EPFD rules set up more than a decade ago, see things differently.

“The plenary text uses the term ‘regulatory consequences’ and the results of the studies will be presented to WRC-27,” a spokesperson for the Alliance for Satellite Broadband said via email.

“In other words, there are paths to study and potentially revise epfd limits at WRC-27.”

The spokesperson did not detail what these paths could be.

Amazon operates two prototypes for a proposed NGSO broadband constellation of more than 3,200 satellites that the company plans to start deploying next year.

There are currently more than 5,000 broadband satellites in SpaceX’s NGSO Starlink constellation — easily the world’s largest by number.

In a letter seen by SpaceNews that SpaceX said it sent the Federal Communications Commission Dec. 14, the company said the approved studies “should result in updated regulations as soon as 2027 that allow next-generation satellite system to increase their power and capacity, which will allow them to connect more people around the world with no consequences for GSO satellite operators.”

David Goldman, SpaceX vice president of satellite policy, also called on the FCC “to make clear the intention of WRC-23 that the radio regulations can be updated in 2027” in the letter, “and to correct those who are misrepresenting the record to try to delay updates that will be critical to connecting more people as expeditiously as possible.”

Viasat, a GSO operator that earlier warned reviewing satellite transmission power limits risked impeding investments and innovation in the orbit, strongly dismissed the idea that regulators have created a path for EPFD regulatory changes to be proposed at WRC-27.

“WRC-23 saw many dozens of nations come together to firmly reject an attempt to change the rules that protect GSO services from interference,” a Viasat spokesperson said via email.

“There is no future WRC agenda item on the possibility of increasing NGSO interference into GSOs for WRC-27 or WRC-31. International consensus also directed that this rejection not be bypassed through procedural means.”

Hazem Moakkit, vice president of spectrum strategy at GSO operator Intelsat, which has plans for an NGSO constellation, said there may be ways to present EPFD changes at WRC-27, “albeit difficult.” Space News