An active protection system is a system (usually for a military application) designed to prevent line-of-sight guided anti-tank missiles/projectiles from acquiring and/or destroying a target.Electronic countermeasures that alter the electromagnetic, acoustic or other signature(s) of a target thereby altering the tracking and sensing behavior of an incoming threat (e.g., guided missile) are designated softkill measures.Measures that physically counterattack an incoming threat thereby destroying/altering its payload/warhead in such a way that the intended effect on the target is severely impeded are designated hardkill measures.