SpaceX today received US approval to deploy 7,518 broadband satellites, in addition to the 4,425 satellites that were approved eight months ago.

The Federal Communications Commission voted to let SpaceX launch 4,425 low-Earth orbit satellites in March of this year. SpaceX separately sought approval for 7,518 satellites operating even closer to the ground, saying that these will boost capacity and reduce latency in heavily populated areas. That amounts to 11,943 satellites in total for SpaceX's Starlink broadband service.

SpaceX "proposes to add a very-low Earth orbit (VLEO) NGSO [non-geostationary satellite orbit] constellation, consisting of 7,518 satellites operating at altitudes from 335km to 346km," the FCC said in the draft of the order that it approved unanimously today. The newly approved satellites would use frequencies between 37.5 and 42GHz for space-to-Earth transmissions and frequencies between 47.2 and 51.4GHz for Earth-to-space transmissions, the FCC said.

"After review of the record, we conclude that granting of the SpaceX application will serve the public interest," subject to conditions related to power levels, avoidance of interference with other systems, and prevention of space debris, the FCC said.

The FCC today also approved US market entry for smaller satellite systems being built by Kepler Communications, Telesat Canada, and LeoSat. These systems consist of 140 satellites for Kepler, 117 satellites for Telesat, and 78 satellites for LeoSat, the FCC said. Unlike SpaceX, these three satellite systems would get their primary approvals from foreign governments, but they still need FCC approval for access to the US market.

"From providing high-speed broadband services in remote areas to offering global connectivity to the Internet of Things through 'routers in space' for data backhaul, I'm excited to see what services these proposed constellations have to offer," FCC Chairman Ajit Pai said today. "Our approach to these applications reflects this commission's fundamental approach: encourage the private sector to invest and innovate and allow market forces to deliver value to American consumers."

Cable-like latency

SpaceX's initial 4,425 satellites are expected to orbit at altitudes of 1,110km to 1,325km, a fraction of the altitude of traditional broadband satellites. Because of the low orbits, SpaceX says its broadband network will have latencies as low as 25ms, similar to cable or fiber systems. SpaceX has also said it will provide gigabit speeds and that it will provide broadband access worldwide.

FCC rules require the launch of 50 percent of satellites within six years of authorization and all of them within nine years unless a waiver is granted.

For the batch of 7,518 satellites, SpaceX asked the FCC to apply the six-year milestone only to an initial deployment of 1,600 satellites. But the FCC denied the request, saying that "SpaceX has not provided sufficient grounds for a waiver of the Commission's final implementation milestone requirement."

SpaceX thus has to deploy half of the 7,518 newly approved satellites within six years and the remaining satellites within nine years unless it successfully re-applies for a waiver.

"SpaceX can resubmit this request in the future, when it will have more information about the progress of the construction and launching of its satellites and will therefore be in a better position to assess the need and justification for a waiver," the FCC wrote.

The FCC's March 2018 approval of SpaceX's first batch of satellites required SpaceX to launch 50 percent of the 4,425 satellites by March 2024 and all of them by March 2027.

The FCC today also voted to start the process of letting satellites in low Earth orbit use certain frequency bands to provide services to ships, airplanes, and vehicles.