Northrop Grumman Corp. of Los Angeles said it has received a radio development contract potentially worth up to $240 million from Lockheed Martin.

The program, in which Lockheed is the lead contractor, is developing a communications system for the Department of Defense that could be used by the Department of Homeland Security.

The initial 56-month $187 million subcontract for what is being called the Airborne and Maritime/Fixed Station and Joint Tactical Radio System will be worth more if all options are exercised, Northrop said Tuesday. The development activities will take place in San Diego, with supportability studies conducted in Sierra Vista, Ariz.

In a separate deal, a Northrop division received a $20.8 million contract from the Air Force to develop technology needed on the B-52 aircraft, the Pentagon said late Monday.