PARIS — Western Europe, whose biggest markets are dominated by a duopoly of SES and Eutelsat of Paris, is generally viewed as commanding the world’s highest satellite lease prices.

In addition to Thor 5 and Thor 6, Telenor in mid-2010 inaugurated a new orbital slot, at 4 degrees west, with its Thor 3 satellite. Launched into the 1 degree west slot in 1998, Thor 3 is operated in inclined orbit, which means it no longer is stabilized on its north-south axis. Telenor expects the satellite to continue operations this way for between four and nine more years.

Thor 7’s Ka-band payload, in addition to serving maritime users with high-speed data links, will also seek customers in the aviation and military markets, according to Telenor.

Inmarsat’s three Global Xpress satellites, which are also targeting the maritime, aeronautical and military markets, are scheduled to be in service starting in 2013.

Inmarsat has said it will be able to deliver 50 megabits per second of capacity to 50-centimeter dishes on users’ mobile platforms.

Telenor Satellite Broadcasting’s chief technical officer has concluded that Thor 7, by using adaptive coding and high-power spot beams, will be able to offer the same throughput speed to dishes as small as 30 centimeters, according to a Telenor presentation on Thor 7.

Halsaa said Telenor, which has considerable experience in delivering fixed and mobile communications services in Ku-band, has concluded that the rain-fade issue associated with Ka-band has been exaggerated.

“I remember this when the industry began using Ku-band,” Halsaa said. “People were concerned about rain attenuation there, too. I think developments in technology will overcome this and it will not be a serious issue for us. If you have good spot beams and sufficient power, you can overcome those setbacks.”

Telenor will be competing with its sometime partner, Intelsat of Luxembourg and Washington, which is deploying seven Ku-band beams on four of its satellites to offer, in Ku-band, a maritime service similar to Inmarsat’s planned Global Xpress.

Intelsat officials have said Ku-band user equipment is better known and less expensive than Ka-band hardware, and that rain fade will be an issue on certain maritime routes.

Halsaa said that Telenor, which is already providing maritime links through its existing satellites, would like to retain its Ku-band licenses for the more-profitable television business, and that it does not have enough Ku-band capacity to serve the maritime market’s expected growth. That too was part of the reason for the move to Ka-band.

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