Electronic warfare, or EW, is the use or control of electro-magnetic energy either in defense, or for the purposes of a military attack on an enemy. There are three components of electronic warfare: electronic countermeasures or electronic attack, electronic counter-countermeasures or electronic protection, and electronic warfare support measures.
Electromagnetism and the electromagnetic spectrum. Electromagnetism is the branch of physics devoted to the study
of electric and magnetic phenomena. Its focus is electromagnetic force, which, along with gravitation and the strong and weak nuclear forces, is one of the four fundamental interactions in nature. Electromagnetic energy is conveyed by means of radiation, which transfers energy without the requirement of a medium such as air or water. Sunlight, which travels to Earth through the vacuum of space, is electromagnetic energy.
Electromagnetic waves travel at the speed of light, and, as their name indicates, involve both electric and magnetic components. If one holds one's right hand, palm perpendicular to the floor and thumb upright, the fingers indicate the direction that an electromagnetic wave is moving; the thumb points in the direction of the electrical field, as does the heel of the hand; and the palm and the back of the hand indicate the direction of the magnetic field, which is perpendicular both to the electrical field and the direction of wave propagation.
The electromagnetic spectrum is the complete range of electromagnetic waves on a continuous distribution from a very low range of frequencies and energy levels, with a correspondingly long wavelength, to a very high range of frequencies and energy levels, with a correspondingly short wavelength. Included on the electromagnetic spectrum are—in order of energy levels, from lowest to highest—radio waves and microwaves; infrared, visible, and ultraviolet light; x rays, and gamma rays. Although each occupies a definite place on the spectrum, the divisions between them are not firm; as befits the nature of a spectrum, one simply "blurs" into another.
Using electromagnetic energy in warfare. The uses of electromagnetism for war are myriad, and range from the application of radar for navigation and locating targets to the use of electronic bombs or "e-bombs" to disrupt an enemy's mechanical and electromagnetic systems. Electromagnetic energy can be used to confuse or deceive an enemy, as for instance in radar-jamming applications or the propagation of misleading signals. It can also be used directly as a weapon to disable infrastructure.
The three principal components of electronic warfare are:
- Electronic attack or electronic countermeasures: The use of electromagnetic or directed energy against personnel or equipment with the aim of degrading or destroying combat capabilities.
- Electronic protection or electronic countercountermeasures: Efforts or equipment directed toward the protection of persons or material from the effects of electronic warfare. These includes the unintended sideeffects of friendly electronic warfare, as well as enemy actions undertaken for the purpose of degrading or destroying one's combat capabilities.
- Electronic warfare support: Actions and resources committed toward locating, identifying, and if necessary intercepting or neutralizing sources of electromagnetic energy that pose an immediate threat.
█ FURTHER READING:
Browne, J. P. R. Electronic Warfare. London: Brassey's, 1998.
Hoffman, Lance J. Rogue Programs: Viruses, Worms, and Trojan Horses. New York: Van Nostrand Reinhold, 1990.
Price, Alfred. War in the Fourth Dimension: U.S. Electronic Warfare, from the Vietnam War to the Present. London: Greenhill, 2001.
Schleher, D. Curtis. Electronic Warfare in the Information Age. Boston: Artech House, 1999.
Wall, Robert. "Focus on Iraq Shapes Electronic, Info Warfare." Aviation Week & Space Technology. 157, no. 19 (November 4, 2002): 34–35.
——. "Military Launches New EW Efforts." Aviation Week & Space Technology. 157, no. 19 (November 4,2002): 35–43.