Usually while they were up, the periscope antenna would pull down the signal from the navigation satellite, the globalpositioning system.

High-frequency signals winged upward, where they made contact with a navigation satellite, and information flashed downward.

The HP version will be used to launch a constellation of seven navigation satellites between 2010 and 2012.

The first navigation satellites were launched by a Delta rocket in 1989.

It is thought that some of these represent navigation satellites for Soviet submarines.

In the reverse, the niobium portion depicts navigation satellites orbiting the Earth.

He said the navigation satellites, part of a new Soviet worldwide network, were of little value in their present orbit.

In fact, the idea of Europeans starting a constellation of 30 navigation satellites was, from the start, difficult to get off the ground.

It would be updated in a few minutes from orbiting navigation satellites.

Judith slipped on her goggles and scanned the gray skies for navigation satellites.