Northrop Grumman has received a $122 million contract to install and sustain Counter-Rocket, Artillery and Mortar (C-RAM) systems at bases in Iraq and Afghanistan. The contract includes options that could raise the value of the contract to $311 million.

The C-RAM system, which first went into the field more than six years ago, provides early warning of incoming indirect fire, officials said. The system integrates artillery and air-defense sensors, a commercial warning system and a Navy-developed interceptor to protect personnel.