A US Air Force global positioning system block IIR (GPS IIR-M) satellite, modernised by Lockheed Martin has been successfully launched aboard a Delta II rocket.

The satellite will join six IIR-M satellites and 12 other operational Block IIR satellites within a 30-spacecraft constellation that will be operated by the air force space command’s second space operations squadron.

The modernised satellite features a modernised antenna panel to increase signal power to receivers on the ground as well as two new military signals for improved accuracy, enhanced encryption and anti-jamming capabilities.

The system is also equipped with a second civil signal that offers an open access signal on a different frequency.

US Air Force GPS Wing Commander Col. Dave Madden said that they are looking forward to successfully executing a smooth and efficient on-orbit checkout and making the advanced satellite operational for the warfighter and civil users around the globe.

The GPS II constellation of 21 satellites were originally built by Lockheed Martin and will be followed by the next generation GPS IIIA, system expected to be launched in 2014.