- Early warning radar
An early warning radar is any radar system used primarily for the long-range detection of its targets, i.e., allowing defences to be alerted as early as possible before the intruder reaches its target, giving the defences the maximum time in which to operate. This contrasts it with systems used primarily for tracking or gun laying, which tend to be shorter range but offer much higher accuracy.
The first early warning radars were the British Chain Home, the US CXAM (Navy) and SCR-270 (Army), and the German Freya. By modern standards these were quite short range, typically about 100 to 150 miles. This "short" distance is a side effect of radio propagation at the long wavelengths being used at the time, which were generally limited to line-of-sight. Although techniques for long-range propagation were known and widely used for shortwave radio, the ability to process the complex return signal was simply not possible at the time.
Starting in the 1950s, a number of over the horizon radars were developed that greatly extended detection ranges, generally by bouncing the signal off the ionosphere. Perhaps the most capable of these systems was the DEW Line, although other examples have since been built with even better performance. An alternate early warning design was the McGill Fence, which provided "line breaking" indication across the middle of Canada, with no provision to identify the target's exact location or direction of travel.
Today the early warning role has been supplanted to a large degree by airborne early warning platforms. By placing the radar on an aircraft, the line-of-sight to the horizon is greatly extended. This allows the radar to use high-frequency signals, offering high resolution, while still offering long range. A major exception to this rule are radars intended to warn of ballistic missile attacks, like BMEWS, as the high altitude exo-atmospheric trajectory of these weapons allows them to be seen at great ranges even from ground-based radars.
1950s through 70s
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early warning radar — ankstyvojo aptikimo radaras statusas T sritis radioelektronika atitikmenys: angl. early warning radar; early warning station vok. Frühwarnradar, n; Frühwarnstation, f rus. радиолокационная станция дальнего обнаружения, f; радиолокационная станция … Radioelektronikos terminų žodynas
early-warning radar — noun : a set or line of radar sets operating in air defense on the perimeter or outward from the defended area to give the earliest possible warning of approaching airplanes * * * early warning radar, a radar set or system designed to detect… … Useful english dictionary
early warning radar — noun a radar that is part of an early warning system • Hypernyms: ↑radar, ↑microwave radar, ↑radio detection and ranging, ↑radiolocation • Part Holonyms: ↑early warning system … Useful english dictionary
early-warning radar — All the radars including long , medium , and short range and medium and low level that detect and warn of the approach of intruding aircraft and missiles early enough to allow interception as far away from the intended target as possible … Aviation dictionary
airborne early warning radar — ankstyvojo aptikimo orlaivio radaras statusas T sritis radioelektronika atitikmenys: angl. airborne early warning radar vok. Frühwarnbordradargerät, n rus. самолётная радиолокационная станция дальнего обнаружения целей, f pranc. radar aéroporté à … Radioelektronikos terminų žodynas
microwave early warning radar — mikrobanginis ankstyvojo aptikimo radaras statusas T sritis radioelektronika atitikmenys: angl. microwave early warning radar vok. Mikrowellen Frühwarnungsradarsystem, n rus. микроволновая радиолокационная станция дальнего обнаружения, f;… … Radioelektronikos terminų žodynas
early warning station — ankstyvojo aptikimo radaras statusas T sritis radioelektronika atitikmenys: angl. early warning radar; early warning station vok. Frühwarnradar, n; Frühwarnstation, f rus. радиолокационная станция дальнего обнаружения, f; радиолокационная станция … Radioelektronikos terminų žodynas
early-warning aircraft — An aircraft specially equipped with early warning radar to detect aircraft and missiles at as great a distance as possible. The aircraft may have some capabilities for controlling friendly aircraft. The E2C Hawkeye AEW (airborne early warning)… … Aviation dictionary
early warning system — noun a network of radar installations designed to detect enemy missiles or aircraft while there is still time to intercept them • Hypernyms: ↑network, ↑electronic network • Part Meronyms: ↑early warning radar … Useful english dictionary
radar early-warning satellite — radarinis ankstyvojo aptikimo palydovas statusas T sritis radioelektronika atitikmenys: angl. radar early warning satellite vok. Frühwarnradarsatellit, m rus. спутник с радиолокационной станцией дальнего обнаружения, m; спутник с радиолокационной … Radioelektronikos terminų žodynas