The preliminary design review (PDR) of the US Air Force global positioning system (GPS) spacecraft, GPS III, has been jointly completed by Lockheed Martin, ITT and General Dynamics.

The next-generation spacecraft will advance the position, navigation and timing services and will offer advanced anti-jam capabilities for better system security, accuracy and reliability.

The completion of the review means that the design meets warfighter and civil requirements.

The PDR, including a review of 70 subsystems and assembly PDRs, is a part of a $3bn development and production contract to the companies for producing up to 12 GPS IIIA satellites to be launched from 2014.

GPS IIIA satellites will have new international civil signal (L1C) and increased M-code anti-jam power with full earth coverage for military users unlike the existing ones.

The PDR will be followed by the critical design review phase.

The GPS series offers critical situational awareness and precision weapon guidance for the military. It also supports civil, scientific and commercial functions such as air traffic control, ATM banking and the internet.