This is America’s C-RAM Weapon System
Counter rocket, artillery, and mortar, abbreviated C-RAM, is a set of systems used to detect and/or destroy incoming rockets, artillery, and mortar rounds in the air before they hit their ground targets, or simply provide early warning.
The intercept capability of C-RAM is effectively a land version of weapons such as the Phalanx CIWS radar-controlled rapid-fire gun for close-in protection of vessels from missiles; either weapon system also uses a forward-looking infrared camera to allow a defender to visually identify these target threats before engaging the targets.
One major difference between the land- and sea-based variants is the choice of ammunition. Whereas naval Phalanx systems fire tungsten armour-piercing rounds, the C-RAM uses the 20mm ammunition, originally developed for the M163 Vulcan air defence system. These rounds explode on impact with the target, or on tracer burnout, thereby greatly reducing the risk of collateral damage from rounds that fail to hit their target.