SpaceX has opened a new window into its ambitious plans for a global satellite broadband data network, thanks to an earth-station license application filed with the Federal Communications Commission.

The application, filed on behalf of a sister company called SpaceX Services, seeks blanket approval for up to a million earth stations that would be used by customers of the Starlink satellite internet service. The stations would rely on a flat-panel, phased-array system to transmit and receive signals in the Ku-band to and from the Starlink constellation.

Those satellites have already received clearance from the FCC, and SpaceX plans to launch the first elements of the initial 4,425-satellite constellation this year, using Falcon 9 rockets. The company sent up its first two experimental broadband satellites last year and has been tweaking its plans for Starlink as a result of those space-to-ground tests. Eventually, SpaceX wants to build up the network to take in as many as 12,000 satellites in low Earth orbit.

SpaceX’s facility in Redmond, Wash., is playing the lead role in developing the satellite system. Last year, the Redmond office went through a management shakeup aimed at accelerating progress on Starlink.

The application filed with the FCC on Feb. 1 focuses on the receiving end of the space-based service. “This application takes the next step by seeking authority for the end-user customers’ earth stations that incorporate advanced technologies to enable highly efficient use of the spectrum and enhance the customer’s broadband experience,” SpaceX executives say in their filing.

They say the system has been engineered “to achieve a high degree of flexibility to facilitate spectrum sharing with other authorized satellite and terrestrial systems.”

In a technical annex, SpaceX argues that licensing rules focusing on antenna performance standards shouldn’t apply to the planned earth stations, since the FCC has recognized that those standards may not be appropriate for satellite networks in low Earth orbit, as opposed to traditional satellites in geostationary Earth orbit.

The FCC hasn’t yet taken any action on SpaceX Services’ earth station licensing application, which relates to operations in the United States (including Alaska and Hawaii), plus Puerto Rico and the U.S. Virgin Islands. SpaceX says it’s not providing any comment beyond what’s in the application.

SpaceX CEO Elon Musk has said the Starlink project aims is to provide high-speed, reliable and affordable broadband data services to consumers in the U.S. and around the world, including an estimated 3.8 billion people who are underserved by existing networks. When he unveiled the project four years ago in Seattle, he said revenue from the internet service would pay for his vision of creating a city on Mars.

If SpaceX sticks to Musk’s timetable, Starlink could go live in the 2020 time frame.

SpaceX is currently in the throes of a $500 million financing round that’s aimed at giving a boost to Starlink as well as development of the company’s Starship super-rocket.

A million earth stations may sound like a lot, but it pales in comparison with Dish’s subscriber base of 10.3 million customers for its satellite-based Dish TV service.

Several other ventures are planning satellite constellations in low Earth orbit to provide global internet access, and signal interference could emerge as a critical issue in the licensing process for earth stations. SpaceX’s top rivals include the international OneWeb consortium, backed by Airbus, SoftBank and other high-profile players; and Telesat, Canada’s largest satellite company.

In a technical analysis conducted for last October’s International Astronautical Congress, MIT researchers said the limiting factor for SpaceX’s satellite service would be the ground segment, “as they need to deploy a very large number of ground stations and gateways to operate at full power.” The researchers said Telesat had the most effective system in terms of bandwidth per satellite.

Check out Professor Mark Handley’s “Simulating Starlink” page on the University College London website for more about how SpaceX’s constellation of broadband data satellites could work.