Electronic counter-countermeasures (ECCM) is a part of electronic warfare which includes a variety of practices which attempt to reduce or eliminate the effect of electronic countermeasures (ECM) on electronic sensors aboard vehicles, ships and aircraft and weapons such as missiles. ECCM is also known as electronic protective measures (EPM), chiefly in Europe. In practice, EPM often means resistance to jamming. A more detailed description defines it as the electronic warfare operations taken by a radar to offset the enemy's countermeasure.
Ever since electronics have been used in battle in an attempt to gain superiority over the enemy, effort has been spent on techniques to reduce the effectiveness of those electronics. More recently, sensors and weapons are being modified to deal with this threat. One of the most common types of ECM is radar jamming or spoofing. This originated with the Royal Air Force's use of what they codenamed Window during World War II, which Americans referred to as chaff. It was first used during the Hamburg raid on July 24-25, 1943. The night fighters outfitted with Window had prong antennae stuck out from their noses, allowing their radars a range of four miles in a 70 degree cone. Jamming also may have originated with the British during World War II, when they began jamming German radio communications. These efforts include the successful British disruption of German Luftwaffe navigational radio beams.
In perhaps the first example of ECCM, the Germans increased their radio transmitter power in an attempt to 'burn through' or override the British jamming, which by necessity of the jammer being airborne or further away produced weaker signals. This is still one of the primary methods of ECCM today. For example, modern airborne jammers are able to identify incoming radar signals from other aircraft and send them back with random delays and other modifications in an attempt to confuse the opponent's radar set, making the 'blip' jump around wildly and become impossible to range.
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Les paillettes sont des filaments métalliques utilisés pour brouiller un radar. Elles sont inefficaces pour brouiller les missiles à guidage infrarouge de type « tire et oublie ». Elles peuvent aussi aider à la détection d'un objet ou être utilisées en météorologie. Elles peuvent se présenter sous la forme d'aiguilles, de bandelettes ou de rubans. vignette|Bandelettes de « Window ». Ce type de contremesure est apparu au cours de la Seconde Guerre mondiale avec l'invention par les Britanniques du système « Window ».
An electronic countermeasure (ECM) is an electrical or electronic device designed to trick or deceive radar, sonar, or other detection systems, like infrared (IR) or lasers. It may be used both offensively and defensively to deny targeting information to an enemy. The system may make many separate targets appear to the enemy, or make the real target appear to disappear or move about randomly. It is used effectively to protect aircraft from guided missiles. Most air forces use ECM to protect their aircraft from attack.
vignette|Le Grumman EA-6 Prowler est un avion de guerre électronique utilisé par l'US Navy vignette|Boeing EA-18G Growler reprenant la relève des EA-6 à partir de 2009. La guerre électronique consiste en l'exploitation des émissions radioélectriques d'un adversaire et, inversement consiste à l'empêcher d'en faire autant. Il s'agit donc de toutes les opérations visant à acquérir la maîtrise du spectre électromagnétique, pour intercepter et/ou brouiller les ordres ou informations circulant dans les systèmes de communication de l'adversaire.
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