Northrop Grumman Corp. will supply navigation systems for a next-generation military satellite communications system under a subcontract from Lockheed Martin Corp., Northrop announced July 17.

Under the initial $4 million contract, Northrop’s navigation systems division will provide inertial navigation units for the first two Mobile User Objective System (MUOS) satellites for the U.S. Navy. Lockheed Martin was awarded a $2.1 billion contract to build the first two MUOS satellites and is scheduled to hand over the spacecraft to the Navy in 2010.

MUOS is a next-generation narrowband military satellite communications system designed to improve communications for U.S. forces on the move.