Anti-radiation missile Anti-radiation missile An anti-radiation missile (ARM) is a missile designed to detect and home in on an enemy radio emission source. Typically, these are designed for use against an enemy radar, although jammers and even radios used for communications can also be targeted in this manner. Most ARM designs to date have been intended for use against ground-based radars. Commonly carried by specialist aircraft in the Suppression of Enemy Air Defenses (SEAD) role (known to the United States Air Force as "Wild Weasels"), the primary purpose of this type of missile is to degrade enemy air defenses in the first
Negative refraction propagation direction of the light, thus the sign of "n" must be chosen to match the physical situation. The principal symptom of negative refraction is just that – light rays are refracted on the "same" side of the normal on entering the material, as indicated in the diagram, and by a suitably general form of Snell's law. Negative refraction Negative refraction is the name for an electromagnetic phenomenon where light rays are refracted at an interface in the reverse sense to that normally expected. Such an effect can be obtained using a metamaterial which has been designed to achieve a