Updated May 26, 2020 with the correct number of companies that had proposed non-geosynchronous satellite constellations.

WASHINGTON — As the U.S. Federal Communications Commission prepares to vote on satellite constellations from four companies in mid-November, another satellite operator is reducing the size of its proposed constellation.

Viasat of Carlsbad, California, modified its design for a medium-Earth-orbit constellation that would consist of 20 telecom satellites instead of 24 as originally envisioned, the FCC said Nov. 2.

The smaller constellation would orbit in four orbital pathways in 8,200-kilometer orbits, with five satellites per pathway. The constellation would otherwise stay largely the same as first described to regulators two years ago, according to Viasat.

The FCC is scheduled to vote Nov. 15 on proposed constellations from Internet-of-Things startup Kepler Communications and high speed broadband startup LeoSat, along with expansions to approved constellations from SpaceX and Telesat. Chairman Ajit Pai said in an Oct. 24 blog post that the commission intends to approve all four requests, allowing each company to provide telecom services in the United States with their systems.

Since 2016, the FCC has approved three large broadband constellations designed for low Earth orbits: 117 satellites for Telesat, 720 satellites for OneWeb, and 4,425 satellites for SpaceX.

The commission has also given SES permission to add 26 more connectivity satellites to its O3b constellation in medium Earth orbit (MEO) and approved Audacy’s MEO three-satellite relay network, a 12-satellite video and data constellation for Karousel in highly elliptical orbits, and a pair of arctic broadband satellites for Space Norway, also in highly elliptical orbits.

In total, 12 companies have proposed constellations to the FCC for new satellite systems that would operate in orbits other than the commonly used geosynchronous circle 36,000 kilometers above the Earth. Viasat is one of three remaining companies whose constellations have yet to come up for vote. Only Boeing, which said earlier this year it hasn’t made much progress on its constellation idea, and Theia Holdings, a little-known company that pitched to regulators a dual-purpose telecom and remote-sensing constellation, have not had votes scheduled.

Viasat CEO Mark Dankberg made a rare mention of Viasat’s constellation program in August, saying a medium-Earth-orbit fleet could complement the geosynchronous satellites the company uses today.

Viasat, in an FCC document filed Sept. 27, said its smaller 20-satellite MEO constellation would still have global coverage, but would reduce the risk of signal interference with other non-geosynchronous constellations by 17 percent.

Viasat is one of several operators to have modified its constellation plans since 2016. The new approvals SpaceX is seeking cover an additional 7,518 satellites in V-band, a rarely used spectrum.

Telesat wants to double its approval, adding another 117 satellites that, like SpaceX, would use V-band spectrum.

OneWeb also asked the FCC to OK 1,200 more satellites in March, although its new request has not yet been scheduled for a vote.