PARIS — Start-up satellite Internet backbone service provider O3b Networks has raised $137 million in fresh financing and has contracted for the construction of four satellites to be launched in 2014, a year after the company’s first eight spacecraft are scheduled to be in orbit, O3b and satellite builder Thales Alenia Space announced Nov. 10.

O3b’s biggest shareholder, satellite fleet operator SES of Luxembourg, on Nov. 11 said it had contributed $35 million to the latest financing round, which will increase SES’s equity stake in the company to 45 percent in 2013, up from 35.6 percent.

In a conference call with journalists, SES Chief Executive Romain Bausch said O3b has received “a very good response” from its core markets in Africa, Latin America and Asia, and that SES expects the constellation eventually to comprise 20 satellites. “This [new financing] demonstrates the confidence of the shareholders” in O3b’s progress, Bausch said.

In a Nov. 10 statement, O3b Chief Executive Steve Collar, who was formerly with SES, said global Internet traffic is likely to grow by more than 30 percent per year in the coming years, and that “a huge proportion of that expansion will be in the emerging markets. O3b is committed to … driving down the cost per megabit per second delivered into the developing world.”

O3b, which is based in Britain’s Channel Islands, said France’s export-credit agency, which already had backed a $510 million loan facility as part of O3b’s initial $1.2 billion financial package, is guaranteeing a new commitment totaling $85 million to be provided by a consortium of banks.

Cannes, France-based Thales Alenia Space confirmed the new order and said the first eight O3b satellites, which passed their critical design review in May, are on schedule for a first launch in early 2013.

The first eight O3b spacecraft will be launched aboard two European versions of Russia’s Soyuz rocket from Europe’s Guiana Space Center spaceport in French Guiana. The vehicle made its inaugural flight in October.

O3b’s satellites will fly in an unusual equatorial orbit at 8,000 kilometers in altitude. Its principal markets are located between 45 degrees north and 45 degrees south latitude. Each satellite will be capable of broadcasting more than 10 gigabits per second of Ka-band throughput to tracking antennas operated by telecommunications companies for wholesale distribution of Internet and cellular-backhaul connectivity.

O3b has said for the past year that it has booked about $600 million in preorders for the service, which it says represents about one-third of the capacity of the initial eight satellites. Adding four more spacecraft, the company said, will increase throughput by 90 percent compared with the initial eight-satellite constellation because of better average elevation angles.

Bausch said the four-satellite order also was made to protect O3b’s business against the possibility of a failure at launch. The system needs more than four satellites to function. With the third group of four satellites arriving a year after the first two, O3b’s business has a buffer in the event one of the first two launches malfunctions, Bausch said.

Peter B. de Selding was the Paris bureau chief for SpaceNews.