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Blip Enhancement
Blip enhancement is an electronic warfare technique used to fool radar. When the radar transmits a burst of energy some of that energy is reflected off a target and is received back at the radar and processed to determine range and angle. The reflected target energy is called skin return, and the amount of energy returning to the originating radar is directly proportional to the radar cross-section (RCS) of the target. Basic radars present the target information on a display and displayed targets are referred to as blips. Based on the relative size of the blips on the display, a radar operator could determine large targets from small targets. When a blip enhancing technique is used, small targets returns are augmented to look like large targets. One early maritime application of this technique was used with an aircraft carrier and its escort ships. Because the aircraft carrier physically dwarfed the other vessels its radar return was much larger making it relatively easy for a r ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Radar
Radar is a system that uses radio waves to determine the distance ('' ranging''), direction ( azimuth and elevation angles), and radial velocity of objects relative to the site. It is a radiodetermination method used to detect and track aircraft, ships, spacecraft, guided missiles, motor vehicles, map weather formations, and terrain. The term ''RADAR'' was coined in 1940 by the United States Navy as an acronym for "radio detection and ranging". The term ''radar'' has since entered English and other languages as an anacronym, a common noun, losing all capitalization. A radar system consists of a transmitter producing electromagnetic waves in the radio or microwave domain, a transmitting antenna, a receiving antenna (often the same antenna is used for transmitting and receiving) and a receiver and processor to determine properties of the objects. Radio waves (pulsed or continuous) from the transmitter reflect off the objects and return to the receiver, giving ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Radar Cross-section
Radar cross-section (RCS), denoted σ, also called radar signature, is a measure of how detectable an object is by radar. A larger RCS indicates that an object is more easily detected. An object reflects a limited amount of radar energy back to the source. The factors that influence this include: *the material with which the target is made; *the size of the target relative to the wavelength of the illuminating radar signal; *the absolute size of the target; *the incident angle (angle at which the radar beam hits a particular portion of the target, which depends upon the shape of the target and its orientation to the radar source); *the reflected angle (angle at which the reflected beam leaves the part of the target hit; it depends upon incident angle); *the polarization of the radiation transmitted and received with respect to the orientation of the target. While important in detecting targets, strength of emitter and distance are not factors that affect the calculation o ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Aircraft Carrier
An aircraft carrier is a warship that serves as a seagoing airbase, equipped with a full-length flight deck and hangar facilities for supporting, arming, deploying and recovering carrier-based aircraft, shipborne aircraft. Typically it is the capital ship of a naval fleet, fleet (known as a carrier battle group), as it allows a naval force to power projection, project seaborne naval aviation, air power far from homeland without depending on local airfields for staging area, staging aerial warfare, aircraft operations. Since their inception in the early 20th century, aircraft carriers have evolved from wooden vessels used to deploy individual tethered reconnaissance balloons, to nuclear marine propulsion, nuclear-powered supercarriers that carry dozens of fighter aircraft, fighters, strike aircraft, military helicopters, airborne early warning and control, AEW&Cs and other types of aircraft such as unmanned combat aerial vehicle, UCAVs. While heavier fixed-wing aircraft such as a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Escort Ship
Ocean escort was a type of United States Navy warship. They were an evolution of the World War II destroyer escort types. The ocean escorts were intended as convoy escorts and were designed for mobilization production in wartime or low-cost mass production in peacetime. They were commissioned from 1954 through 1974, serving in the Cold War and the Vietnam War. Designation The ocean escorts' hull classification symbol was DE, a carryover from the World War II era when vessels of similar size and role were classified as destroyer escorts. DEs were ASW vessels; DEGs were ASW and AAW vessels with the short-range Tartar guided missile added. Ships similar or identical to the World War II destroyer escorts and the Cold War ocean escorts were called "frigates" in most other navies. Outside the US Navy, no other navy appears to have used the ship type of "ocean escort". The closest equivalents in type name are the Soviet and classes, built circa 1954–65. These classes' Russian de ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Missile
A missile is an airborne ranged weapon capable of self-propelled flight aided usually by a propellant, jet engine or rocket motor. Historically, 'missile' referred to any projectile that is thrown, shot or propelled towards a target; this usage is still recognized today with any unguided jet- or rocket-propelled weapons generally described as rocket artillery. Airborne explosive devices without propulsion are referred to as shells if fired by an artillery piece and bombs if dropped by an aircraft. Missiles are also generally guided towards specific targets termed as guided missiles or guided rockets. Missile systems usually have five system components: targeting, guidance system, flight system, engine, and warhead. Missiles are primarily classified into different types based on firing source and target such as surface-to-surface, air-to-surface, surface-to-air and air-to-air missiles. Terminology Missile is derived from Latin "missilis" meaning "that may be ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Retroreflectors
A retroreflector (sometimes called a retroflector or cataphote) is a device or surface that reflects light or other radiation back to its source with minimum scattering. This works at a wide range of angle of incidence, unlike a planar mirror, which does this only if the mirror is exactly perpendicular to the wave front, having a zero angle of incidence. Being directed, the retroflector's reflection is brighter than that of a diffuse reflector. Corner reflectors and cat's eye reflectors are the most used kinds. Types There are several ways to obtain retroreflection: Corner reflector A set of three mutually perpendicular reflective surfaces, placed to form the internal corner of a cube, work as a retroreflector. The three corresponding normal vectors of the corner's sides form a basis in which to represent the direction of an arbitrary incoming ray, . When the ray reflects from the first side, say x, the ray's ''x''-component, ''a'', is reversed to −''a'', while the ''y'' ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
ADM-20 Quail
The McDonnell ADM-20 Quail was a subsonic, jet powered, air-launched decoy cruise missile built by McDonnell Aircraft Corporation. The Quail was designed to be launched by the Boeing B-52 Stratofortress strategic bomber and its original United States Air Force designation was GAM-72 (GAM standing for Guided Aircraft Missile). Quail contained electronics and radar reflectors intended to make it indistinguishable from a B-52 approaching at low altitude. This would force Soviet defenses to divide their missiles and interceptors between multiple targets, reducing the chance that a bomber would be targeted. Design of an improved version of Quail began in January 1968, with the system being termed the Subsonic Cruise Aircraft Decoy. This program incorporated several significant changes to the starting design before the AGM-86 ALCM was created. Development In 1955 the USAF started a major effort to construct decoy missiles. The goal of this effort was to improve the ability of st ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Corner Reflector
A corner reflector is a retroreflector consisting of three mutually perpendicular, intersecting flat reflective surfaces. It reflects waves incident from any direction directly towards the source, but translated. The three intersecting surfaces often are triangles (forming a tetrahedron) or may have square shapes. Radar corner reflectors made of metal are used to reflect radio waves from radar sets. Optical corner reflectors, called corner cubes or cube corners, made of three-sided glass prisms, are used in surveying and laser ranging. Principle The incoming ray is reflected three times, once by each surface, which results in a reversal of direction. To see this, the three corresponding normal vectors of the corner's perpendicular sides can be considered to form a basis (a rectangular coordinate system) (''x'', ''y'', ''z'') in which to represent the direction of an arbitrary incoming ray, . When the ray reflects from the first side, say ''x'', the ray's ''x'' compon ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Boeing B-52 Stratofortress
The Boeing B-52 Stratofortress is an American long-range, subsonic aircraft, subsonic, jet-powered strategic bomber. The B-52 was designed and built by Boeing, which has continued to provide support and upgrades. It has been operated by the United States Air Force (USAF) since 1955 and was flown by NASA from 1959 to 2007. The bomber can carry up to of weapons and has a typical Range (aeronautics), combat range of around without aerial refueling. After Boeing won the initial contract in June 1946, the aircraft's design evolved from a straight wing, straight-wing aircraft powered by six turboprop engines to the final prototype YB-52 with eight turbojet engines and swept wings. The B-52 took its maiden flight in April 1952. Built to carry nuclear weapons for Cold War Nuclear strategy, deterrence missions, the B-52 Stratofortress replaced the Convair B-36 Peacemaker. The bombers flew under the Strategic Air Command (SAC) until it was disestablished in 1992 and its aircraft abso ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
ADM-141 TALD
The ADM-141A/B TALD was an American decoy missile originally built by Brunswick Corporation for the United States Air Force and the Israeli Air Force. Later it transitioned to joint US/Israeli manufacture with Israeli Military Industries Advanced Systems Division (IMI-ASD). The Tactical Air Launched Decoy (TALD) was intended to confuse and saturate enemy air defenses, as part of an overall SEAD ( Suppression of Enemy Air Defenses) strategy, thus allowing attacking aircraft and weapons a higher probability of penetrating to the target. The Improved TALD (Abbreviated: ITALD) is a turbojet-powered version, granting extended range. History In the 1970s, the Brunswick Corp. developed several unpowered radar decoys, including the Samson, which was produced for the Israeli Air Force by Israel Military Industries (IMI) in the early 1980s. The Samson proved highly successful, prompting the US Navy to purchase about 2000 of them during the mid to late 1980s. The first units entered US ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Luneburg Lens
A Luneburg lens (original German ''Lüneburg-Linse'') is a spherically symmetric gradient-index lens. A typical Luneburg lens's refractive index ''n'' decreases radially from the center to the outer surface. They can be made for use with electromagnetic radiation from visible light to radio waves. For certain index profiles, the lens will form perfect geometrical images of two given concentric spheres onto each other. There are an infinite number of refractive-index profiles that can produce this effect. The simplest such solution was proposed by Rudolf Luneburg in 1944. Luneburg's solution for the refractive index creates two conjugate foci outside the lens. The solution takes a simple and explicit form if one focal point lies at infinity, and the other on the opposite surface of the lens. J. Brown and A. S. Gutman subsequently proposed solutions which generate one internal focal point and one external focal point. These solutions are not unique; the set of solutions are ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
