One of Russia's leading space-industry manufacturers will build four new satellites for the country's global navigation satellite system by the end of 2006, a senior official from the center said Monday

Vladimir Bartenev, the deputy chief designer at the Reshetnev Research and Production Center in the Siberian city of Krasnoyarsk, said three new Glonass-M satellites would be orbited this year and a fourth in 2007. He said there were plans to increase the number of Glonass-M satellites in orbit to six in 2007.

The Glonass system currently has 17 satellites and two laser reflectors in orbit.

The first launch under the project took place on October 12, 1982, but the system only officially started to be used on September 24, 1993. Glonass comprises radio navigation satellites that track the whereabouts of clients on land, at sea and in space.

The satellites currently in use are of two modifications: Glonass and the updated Glonass-M. The latter satellites have a longer service life of seven years and are equipped with updated antenna feeder systems and an additional navigation frequency for civilian users.

A future modification, Glonass-K, is an entirely new model based on a non-pressurized platform, standardized to the specifications of the previous models' platform, Express-1000.

The Glonass-K is a small spacecraft that is considerably lighter than previous models, which makes it less expensive to put into orbit. Improved weight specifications also mean that more carrier rockets can carry it into orbit. The craft's estimated service life has been extended to 10-12 years and a third "civilian" L-range frequency added.

Source: RIA Novosti