US Air Force’s advanced extremely high-frequency (AEHF) military communications satellite built by Lockheed has entered the final integrated system testing phase.

AEHF will provide global, highly secure, protected, survivable communications for warfighters under US defence.

The AEHF will also provide critical survivable, protected and endurable communications to the National Command Authority including presidential conferencing in all levels of conflict.

The AEHF system will succeed the five-satellite Milstar constellation and a single AEHF satellite will provide greater total capacity than the entire Milstar constellation currently on-orbit to improve tactical military communications, such as higher-quality real-time video and quicker access to battlefield maps and targeting data.

The system testing phase will involve executing integrated spacecraft and system test procedures to prepare the vehicle for flight.

The test regime will include a series of factory tests to verify all spacecraft interfaces, demonstrate full functionality and evaluate satellite performance.

The first AEHF spacecraft is due for a 2010 launch aboard an Atlas V launch vehicle followed by the second and the third satellites in 2011 and 2012.

The satellite recently completed its environmental testing phase.