Airborne ground surveillance (AGS) refers to a class of military airborne radar system (surveillance aircraft) used for detecting and tracking ground targets, such as vehicles and slow moving helicopters, as opposed to Airborne early warning and control, whose primary role is detecting and tracking aircraft in flight. Antenna beam width should be very small to enhance resolution. This antenna size limitation demands high frequency (GHz range) of operation, to be operated in this mode. AGS radar is typically a medium or low power radar. It includes both maritime and land surveillance. Today, UAVs perform this operation, which often uses optical aids for surveillance.