329 relations: Acronym, Acronyms and abbreviations in avionics, Active electronically scanned array, Active radar homing, Aegis Combat System, Air Member for Materiel, Air Ministry, Air traffic control, Airborne early warning and control, Aircraft, Aircraft flight control system, Airport, Albert H. Taylor, Alexander Stepanovich Popov, Alfred Lee Loomis, Amplifier, Amplitude-comparison monopulse, AN/APG-77, Anomalous propagation, Antenna (radio), Antenna aperture, Antenna gain, Anti-aircraft warfare, Anti-ballistic missile, Aperture synthesis, Arnold Wilkins, Atmosphere of Earth, Atmospheric duct, Attack on Pearl Harbor, Australia, Automatic gain control, Aviation, Azimuth, AZUSA, Ballistic Missile Early Warning System, Baltic Sea, Battle of Britain, Bawdsey Manor, BBC, Beat (acoustics), Black body, Boltzmann constant, Broadcasting, C band (IEEE), Canada, Cavity magnetron, Centimetre, Chaff (countermeasure), Chain Home, Chain Home Low, ..., Chirplet transform, Christian Hülsmeyer, Circular polarization, Close-in weapon system, Coastal artillery, Coherence (physics), Coherer, Cologne, Conical scanning, Constant false alarm rate, Continuous-wave radar, Coolanol, Corner reflector, Crossed-field amplifier, Crust (geology), Data processing system, Death ray, Detection, Diamagnetism, Diffraction, Digital elevation model, Digital signal processing, Direction finding, Doppler effect, Doppler radar, Dowding system, Duplexer, Dust storm, Electrical resistance and conductance, Electrical resistivity and conductivity, Electromagnetic radiation, Electromagnetic spectrum, Electronic counter-countermeasure, Electronic countermeasure, Electronic warfare, Empire of Japan, English language, Ester, Extremely high frequency, Figure of the Earth, Flicker noise, Fractal, French Third Republic, Frequency, Frequency-hopping spread spectrum, FuG 200 Hohentwiel, Gallium arsenide, General Post Office, Geologist, German language, Gneiss-2, Grease pencil, Ground-controlled approach, Ground-penetrating radar, Gulag, H2S (radar), Hail spike, Heinrich Hertz, Hertz, Heterodyne, High frequency, Hugh Dowding, Hydrolysis, Hygroscopy, Imaging radar, Imperial Russian Navy, Infrared, Institute of Electrical and Electronics Engineers, Institution of Electrical Engineers, Interferometry, International Telecommunication Union, Inverse-square law, Ionosphere, ITU Radio Regulations, Jitter, Johnson–Nyquist noise, K band (IEEE), Ka band, Kingdom of Hungary (1920–46), Kingdom of Italy, Klystron, Kriegsmarine, Kronstadt, Ku band, Kwajalein Atoll, L band, Laser, Lawrence A. Hyland, Leo C. Young, Lidar, Light, Lightning, Line-of-sight propagation, Linear polarization, List of radars, List of UWB channels, Lockheed Martin F-22 Raptor, Look-down/shoot-down, LORAN, Machine learning, Magnetism, Mammut radar, Marine radar, Matched filter, Meteoroid, Meteorology, Metre, Microwave, Mikoyan MiG-31, Military, Millimetre, MIM-104 Patriot, Mirror, Missile, MISTRAM, MIT Radiation Laboratory, Modulation, Monopulse radar, Moon, Motion detector, Motor vehicle, Moving target indication, Multipath propagation, Nap-of-the-earth, National Severe Storms Laboratory, Nautical mile, Nazi Germany, Nearest neighbour algorithm, Netherlands, New Zealand, NEXRAD, Noise (electronics), Noise figure, Noise floor, Nyquist frequency, Oboe (navigation), Omnidirectional antenna, Omniview technology, Optical resolution, Over-the-horizon radar, Parabola, Passive electronically scanned array, Path loss, Pathfinder (RAF), Pavel K. Oshchepkov, Petlyakov Pe-2, Phased array, Plan position indicator, Polarization (waves), Pollution prevention, Popular Science, Potomac River, Precipitation, Precision-guided munition, Primary radar, Probabilistic data association filter, Proximity fuze, Public health surveillance, Pulse compression, Pulse forming network, Pulse repetition frequency, Pulse-Doppler radar, Pulse-Doppler signal processing, Pulsed power, Radar altimeter, Radar astronomy, Radar cross-section, Radar display, Radar engineering details, Radar gun, Radar horizon, Radar navigation, Radar tower, Radar tracker, Radiation-absorbent material, Radio, Radio astronomy, Radio receiver, Radio spectrum, Radio wave, Radiodetermination service, Radiolocation service, Radiolocation-satellite service, Range ambiguity resolution, Rangefinder, Rayleigh scattering, Reflection (physics), Refraction, Refractive index, Relative permittivity, Research vessel, Resonance, Right angle, Robert Morris Page, Robert Watson-Watt, Rockwell B-1 Lancer, Ronald Reagan Ballistic Missile Defense Test Site, Rotation, Rotterdam, Rudolf Kühnhold, S band, Safeguard Program, Saint Petersburg Electrotechnical University, Scattering, SCR-270, Searchlight, Seawater, Secondary surveillance radar, Semi-active radar homing, Sensitivity time control, Severe weather, Shortwave radio, Shot noise, Side lobe, Signal processing, Signal-to-noise ratio, Silicate, Sine wave, Skywave, Slide rule, Solid angle, Sonar, South Africa, Soviet Union, Space rendezvous, Space surveillance, Space-time adaptive processing, Spacecraft, Spark-gap transmitter, Spectrum analyzer, Speed, Speed of light, SS Normandie, Stealth aircraft, Stealth technology, Sun, Sunset, Surveillance, Synthetic-aperture radar, Terrain-following radar, Thinned-array curse, Thomson-CSF, Thunderstorm, Thyratron, Time of flight, Time–frequency analysis, Tizard Mission, Tornado, Track-before-detect, Transmitter, Transponder (aeronautics), Traveling-wave tube, Turbulence, UDOP, Ultra high frequency, Ultra-wideband, Ultraviolet, United Airlines, United Kingdom, United States, United States Army, United States Naval Research Laboratory, United States Navy, V band, Vacuum, Very high frequency, Vessel traffic service, W band, Water vapor, Wave radar, Waveguide, Wavelet, Weather, Weather forecasting, Weather radar, Winter storm, World War II, X band, Zaslon. Expand index (279 more) » « Shrink index
An acronym is a word or name formed as an abbreviation from the initial components in a phrase or a word, usually individual letters (as in NATO or laser) and sometimes syllables (as in Benelux).
This is a list of the acronyms and abbreviations used in avionics.
An active electronically scanned array (AESA), is a type of phased array antenna, that is a computer-controlled array antenna in which the beam of radio waves can be electronically steered to point in different directions without moving the antenna.
Active radar homing (ARH) is a missile guidance method in which a missile contains a radar transceiver (in contrast to semi-active radar homing, which uses only a receiver) and the electronics necessary for it to find and track its target autonomously.
The Aegis Combat System is an American integrated naval weapons system developed by the Missile and Surface Radar Division of RCA, and now produced by Lockheed Martin.
The Air Member for Materiel is the senior Royal Air Force officer responsible for procurement matters: he is a member of the Air Force Board.
The Air Ministry was a department of the Government of the United Kingdom with the responsibility of managing the affairs of the Royal Air Force, that existed from 1918 to 1964.
Air traffic control (ATC) is a service provided by ground-based air traffic controllers who direct aircraft on the ground and through controlled airspace, and can provide advisory services to aircraft in non-controlled airspace.
An airborne early warning and control (AEW&C) system is an airborne radar picket system designed to detect aircraft, ships and vehicles at long ranges and perform command and control of the battlespace in an air engagement by directing fighter and attack aircraft strikes.
An aircraft is a machine that is able to fly by gaining support from the air.
A conventional fixed-wing aircraft flight control system consists of flight control surfaces, the respective cockpit controls, connecting linkages, and the necessary operating mechanisms to control an aircraft's direction in flight.
An airport is an aerodrome with extended facilities, mostly for commercial air transport.
Albert Hoyt Taylor (January 1, 1879 in Chicago, IL – December 11, 1961 in Los Angeles, CA) was an American electrical engineer who made important early contributions to the development of radar.
Alexander Stepanovich Popov (sometimes spelled Popoff; Алекса́ндр Степа́нович Попо́в; –) was a Russian physicist who is acclaimed in his homeland and some eastern European countries as the inventor of radio.
Alfred Lee Loomis (November 4, 1887 – August 11, 1975) was an American attorney, investment banker, philanthropist, scientist, physicist, inventor of the LORAN Long Range Navigation System, and a lifelong patron of scientific research.
An amplifier, electronic amplifier or (informally) amp is an electronic device that can increase the power of a signal (a time-varying voltage or current).
Amplitude-comparison monopulse refers to a common direction finding technique.
The AN/APG-77 is a multifunction low probability of intercept radar installed on the F-22 Raptor fighter aircraft.
Anomalous propagation (sometimes shortened to anaprop or anoprop) includes different forms of radio propagation due to an unusual distribution of temperature and humidity with height in the atmosphere.
In radio, an antenna is the interface between radio waves propagating through space and electric currents moving in metal conductors, used with a transmitter or receiver.
In electromagnetics and antenna theory, antenna aperture, effective area, or receiving cross section, is a measure of how effective an antenna is at receiving the power of electromagnetic radiation (such as radio waves).
In electromagnetics, an antenna's power gain or simply gain is a key performance number which combines the antenna's directivity and electrical efficiency.
Anti-aircraft warfare or counter-air defence is defined by NATO as "all measures designed to nullify or reduce the effectiveness of hostile air action."AAP-6 They include ground-and air-based weapon systems, associated sensor systems, command and control arrangements and passive measures (e.g. barrage balloons).
An anti-ballistic missile (ABM) is a surface-to-air missile designed to counter ballistic missiles (see missile defense).
Aperture synthesis or synthesis imaging is a type of interferometry that mixes signals from a collection of telescopes to produce images having the same angular resolution as an instrument the size of the entire collection.
Arnold Frederic Wilkins OBE (20 February 1907 – 5 August 1985) was a pioneer in developing the use of radar.
The atmosphere of Earth is the layer of gases, commonly known as air, that surrounds the planet Earth and is retained by Earth's gravity.
In telecommunications, an atmospheric duct is a horizontal layer in the lower atmosphere in which the vertical refractive index gradients are such that radio signals (and light rays) are guided or ducted, tend to follow the curvature of the Earth, and experience less attenuation in the ducts than they would if the ducts were not present.
The attack on Pearl Harbor was a surprise military strike by the Imperial Japanese Navy Air Service against the United States naval base at Pearl Harbor, Hawaii Territory, on the morning of December 7, 1941.
Australia, officially the Commonwealth of Australia, is a sovereign country comprising the mainland of the Australian continent, the island of Tasmania and numerous smaller islands.
Automatic gain control (AGC), also called automatic volume control (AVC), is a closed-loop feedback regulating circuit in an amplifier or chain of amplifiers, the purpose of which is to maintain a suitable signal amplitude at its output, despite variation of the signal amplitude at the input.
Aviation, or air transport, refers to the activities surrounding mechanical flight and the aircraft industry.
An azimuth (from the pl. form of the Arabic noun "السَّمْت" as-samt, meaning "the direction") is an angular measurement in a spherical coordinate system.
AZUSA refers to a ground-based radar tracking system installed at Cape Canaveral, Florida and the NASA Kennedy Space Center.
The RCA 474L Ballistic Missile Early Warning System (BMEWS, "474L System", Project 474L) was a United States Air Force Cold War early warning radar, computer, and communications system, for ballistic missile detection.
The Baltic Sea is a sea of the Atlantic Ocean, enclosed by Scandinavia, Finland, Estonia, Latvia, Lithuania, Russia, Poland, Germany and the North and Central European Plain.
The Battle of Britain (Luftschlacht um England, literally "The Air Battle for England") was a military campaign of the Second World War, in which the Royal Air Force (RAF) defended the United Kingdom (UK) against large-scale attacks by Nazi Germany's air force, the Luftwaffe.
Bawdsey Manor stands at a prominent position at the mouth of the River Deben close to the village of Bawdsey in Suffolk, England, about northeast of London.
The British Broadcasting Corporation (BBC) is a British public service broadcaster.
In acoustics, a beat is an interference pattern between two sounds of slightly different frequencies, perceived as a periodic variation in volume whose rate is the difference of the two frequencies.
A black body is an idealized physical body that absorbs all incident electromagnetic radiation, regardless of frequency or angle of incidence.
The Boltzmann constant, which is named after Ludwig Boltzmann, is a physical constant relating the average kinetic energy of particles in a gas with the temperature of the gas.
Broadcasting is the distribution of audio or video content to a dispersed audience via any electronic mass communications medium, but typically one using the electromagnetic spectrum (radio waves), in a one-to-many model.
The C-band is a designation by the Institute of Electrical and Electronics Engineers (IEEE) for a portion of the electromagnetic spectrum in the microwave range of frequencies ranging from 4.0 to 8.0 gigahertz (GHz); however, this definition is the one used by radar manufacturers and users, not necessarily by microwave radio telecommunications users.
Canada is a country located in the northern part of North America.
The cavity magnetron is a high-powered vacuum tube that generates microwaves using the interaction of a stream of electrons with a magnetic field while moving past a series of open metal cavities (cavity resonators).
A centimetre (international spelling as used by the International Bureau of Weights and Measures; symbol cm) or centimeter (American spelling) is a unit of length in the metric system, equal to one hundredth of a metre, centi being the SI prefix for a factor of.
Chaff, originally called Window by the British and Düppel by the Second World War era German Luftwaffe (from the Berlin suburb where it was first developed), is a radar countermeasure in which aircraft or other targets spread a cloud of small, thin pieces of aluminium, metallized glass fibre or plastic, which either appears as a cluster of primary targets on radar screens or swamps the screen with multiple returns.
Chain Home, or CH for short, was the codename for the ring of coastal Early Warning radar stations built by the Royal Air Force (RAF) before and during the Second World War to detect and track aircraft.
Chain Home Low (CHL) was the name of a British early warning radar system operated by the RAF during World War II.
In signal processing, the chirplet transform is an inner product of an input signal with a family of analysis primitives called chirplets.
Christian Hülsmeyer (Huelsmeyer) (25 December 1881 – 31 January 1957) was a German inventor, physicist and entrepreneur.
In electrodynamics, circular polarization of an electromagnetic wave is a polarization state in which, at each point, the electric field of the wave has a constant magnitude but its direction rotates with time at a steady rate in a plane perpendicular to the direction of the wave.
A close-in weapon system (CIWS), is a point-defense weapon system for detecting and destroying short-range incoming missiles and enemy aircraft which have penetrated the outer defenses, typically mounted shipboard in a naval capacity.
Coastal artillery is the branch of the armed forces concerned with operating anti-ship artillery or fixed gun batteries in coastal fortifications.
In physics, two wave sources are perfectly coherent if they have a constant phase difference and the same frequency, and the same waveform.
The coherer was a primitive form of radio signal detector used in the first radio receivers during the wireless telegraphy era at the beginning of the 20th century.
Cologne (Köln,, Kölle) is the largest city in the German federal state of North Rhine-Westphalia and the fourth most populated city in Germany (after Berlin, Hamburg, and Munich).
Conical scanning is a system used in early radar units to improve their accuracy, as well as making it easier to steer the antenna properly to point at a target.
Constant false alarm rate (CFAR) detection refers to a common form of adaptive algorithm used in radar systems to detect target returns against a background of noise, clutter and interference.
Continuous-wave radar is a type of radar system where a known stable frequency continuous wave radio energy is transmitted and then received from any reflecting objects.
Coolanol is a trade name for a series of silicate ester industrial coolants.
A corner reflector is a retroreflector consisting of three mutually perpendicular, intersecting flat surfaces, which reflects waves back directly towards the source, but translated.
A crossed-field amplifier (CFA) is a specialized vacuum tube, first introduced in the mid-1950s and frequently used as a microwave amplifier in very-high-power transmitters.
In geology, the crust is the outermost solid shell of a rocky planet, dwarf planet, or natural satellite.
A data processing system is a combination of machines, people, and processes that for a set of inputs produces a defined set of outputs.
The death ray or death beam was a theoretical particle beam or electromagnetic weapon of the 1920s and 1930s that was claimed to have been invented independently by Guglielmo Marconi, Nikola Tesla, Harry Grindell Matthews, Edwin R. Scott, and Graichen, as well as others.
In general, detection is the extraction of particular information from a larger stream of information without specific cooperation from or synchronization with the sender.
Diamagnetic materials are repelled by a magnetic field; an applied magnetic field creates an induced magnetic field in them in the opposite direction, causing a repulsive force.
--> Diffraction refers to various phenomena that occur when a wave encounters an obstacle or a slit.
A digital elevation model (DEM) is a 3D CG representation of a terrain's surface – commonly of a planet (e.g. Earth), moon, or asteroid – created from a terrain's elevation data.
Digital signal processing (DSP) is the use of digital processing, such as by computers or more specialized digital signal processors, to perform a wide variety of signal processing operations.
Direction finding (DF), or radio direction finding (RDF), is the measurement of the direction from which a received signal was transmitted.
The Doppler effect (or the Doppler shift) is the change in frequency or wavelength of a wave in relation to observer who is moving relative to the wave source.
A Doppler radar is a specialized radar that uses the Doppler effect to produce velocity data about objects at a distance.
The Dowding system was the world's first wide-area ground-controlled interception network, controlling the airspace across the United Kingdom from northern Scotland to the southern coast of England.
A duplexer is an electronic device that allows bi-directional (duplex) communication over a single path.
A dust storm is a meteorological phenomenon common in arid and semi-arid regions.
The electrical resistance of an electrical conductor is a measure of the difficulty to pass an electric current through that conductor.
Electrical resistivity (also known as resistivity, specific electrical resistance, or volume resistivity) is a fundamental property that quantifies how strongly a given material opposes the flow of electric current.
In physics, electromagnetic radiation (EM radiation or EMR) refers to the waves (or their quanta, photons) of the electromagnetic field, propagating (radiating) through space-time, carrying electromagnetic radiant energy.
The electromagnetic spectrum is the range of frequencies (the spectrum) of electromagnetic radiation and their respective wavelengths and photon energies.
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.
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.
Electronic warfare (EW) is any action involving the use of the electromagnetic spectrum or directed energy to control the spectrum, attack of an enemy, or impede enemy assaults via the spectrum.
The was the historical nation-state and great power that existed from the Meiji Restoration in 1868 to the enactment of the 1947 constitution of modern Japan.
English is a West Germanic language that was first spoken in early medieval England and is now a global lingua franca.
In chemistry, an ester is a chemical compound derived from an acid (organic or inorganic) in which at least one –OH (hydroxyl) group is replaced by an –O–alkyl (alkoxy) group.
Extremely high frequency (EHF) is the International Telecommunication Union (ITU) designation for the band of radio frequencies in the electromagnetic spectrum from 30 to 300 gigahertz (GHz).
The figure of the Earth is the size and shape of the Earth in geodesy.
Flicker noise is a type of electronic noise with a 1/f power spectral density.
In mathematics, a fractal is an abstract object used to describe and simulate naturally occurring objects.
The French Third Republic (La Troisième République, sometimes written as La IIIe République) was the system of government adopted in France from 1870 when the Second French Empire collapsed during the Franco-Prussian War until 1940 when France's defeat by Nazi Germany in World War II led to the formation of the Vichy government in France.
Frequency is the number of occurrences of a repeating event per unit of time.
Frequency-hopping spread spectrum (FHSS) is a method of transmitting radio signals by rapidly switching a carrier among many frequency channels, using a pseudorandom sequence known to both transmitter and receiver.
The FuG 200 "Hohentwiel" was a low-UHF band frequency maritime patrol radar system of the Luftwaffe in World War II.
Gallium arsenide (GaAs) is a compound of the elements gallium and arsenic.
The General Post Office (GPO) was officially established in England in 1660 by Charles II and it eventually grew to combine the functions of state postal system and telecommunications carrier.
A geologist is a scientist who studies the solid and liquid matter that constitutes the Earth as well as the processes that shape it.
German (Deutsch) is a West Germanic language that is mainly spoken in Central Europe.
Gneiss-2 was the first Soviet produced airborne radar system, introduced in 1942.
The grease pencil, a wax writing tool also known as a wax pencil, china marker or chinagraph pencil (especially in the United Kingdom), is a writing implement made of hardened colored wax and is useful for marking on hard, glossy non-porous surfaces.
In aviation a ground-controlled approach (GCA), is a type of service provided by air-traffic controllers whereby they guide aircraft to a safe landing, including in adverse weather conditions, based on primary radar images.
Ground-penetrating radar (GPR) is a geophysical method that uses radar pulses to image the subsurface.
The Gulag (ГУЛАГ, acronym of Главное управление лагерей и мест заключения, "Main Camps' Administration" or "Chief Administration of Camps") was the government agency in charge of the Soviet forced labor camp system that was created under Vladimir Lenin and reached its peak during Joseph Stalin's rule from the 1930s to the 1950s.
H2S was the first airborne, ground scanning radar system.
A hail spike or three body scatter spike (TBSS) is an artifact on a weather radar display indicative of large hail.
Heinrich Rudolf Hertz (22 February 1857 – 1 January 1894) was a German physicist who first conclusively proved the existence of the electromagnetic waves theorized by James Clerk Maxwell's electromagnetic theory of light.
The hertz (symbol: Hz) is the derived unit of frequency in the International System of Units (SI) and is defined as one cycle per second.
Heterodyning is a signal processing technique invented in 1901 by Canadian inventor-engineer Reginald Fessenden that creates new frequencies by combining or mixing two frequencies.
High frequency (HF) is the ITU designation for the range of radio frequency electromagnetic waves (radio waves) between 3 and 30 megahertz (MHz).
Air Chief Marshal Hugh Caswall Tremenheere Dowding, 1st Baron Dowding, (24 April 1882 – 15 February 1970) was an officer in the Royal Air Force.
Hydrolysis is a term used for both an electro-chemical process and a biological one.
Hygroscopy is the phenomenon of attracting and holding water molecules from the surrounding environment, which is usually at normal or room temperature.
Imaging radar is an application of radar which is used to create two-dimensional images, typically of landscapes.
The Imperial Russian Navy was the navy of the Russian Empire.
Infrared radiation (IR) is electromagnetic radiation (EMR) with longer wavelengths than those of visible light, and is therefore generally invisible to the human eye (although IR at wavelengths up to 1050 nm from specially pulsed lasers can be seen by humans under certain conditions). It is sometimes called infrared light.
The Institute of Electrical and Electronics Engineers (IEEE) is a professional association with its corporate office in New York City and its operations center in Piscataway, New Jersey.
The Institution of Electrical Engineers (IEE, pronounced I-E-E) was a British professional organisation of electronics, electrical, manufacturing, and Information Technology professionals, especially electrical engineers.
Interferometry is a family of techniques in which waves, usually electromagnetic waves, are superimposed causing the phenomenon of interference in order to extract information.
The International Telecommunication Union (ITU; Union Internationale des Télécommunications (UIT)), originally the International Telegraph Union (Union Télégraphique Internationale), is a specialized agency of the United Nations (UN) that is responsible for issues that concern information and communication technologies.
The inverse-square law, in physics, is any physical law stating that a specified physical quantity or intensity is inversely proportional to the square of the distance from the source of that physical quantity.
The ionosphere is the ionized part of Earth's upper atmosphere, from about to altitude, a region that includes the thermosphere and parts of the mesosphere and exosphere.
The ITU Radio Regulations (short: RR) regulates on law of nations scale radiocommunication services and the utilisation of radio frequencies.
In electronics and telecommunications, jitter is the deviation from true periodicity of a presumably periodic signal, often in relation to a reference clock signal.
Johnson–Nyquist noise (thermal noise, Johnson noise, or Nyquist noise) is the electronic noise generated by the thermal agitation of the charge carriers (usually the electrons) inside an electrical conductor at equilibrium, which happens regardless of any applied voltage.
The IEEE K band is a portion of the radio spectrum in the microwave range of frequencies from 18 to 27 gigahertz (GHz).
The Ka band (pronounced as either "kay-ay band" or "ka band") is a portion of the microwave part of the electromagnetic spectrum defined as frequencies in the range 26.5–40 gigahertz (GHz), i.e. wavelengths from slightly over one centimeter down to 7.5 millimeters.
The Kingdom of Hungary (Hungarian: Magyar Királyság), also known as the Regency, existed from 1920 to 1946 as a de facto country under Regent Miklós Horthy.
The Kingdom of Italy (Regno d'Italia) was a state which existed from 1861—when King Victor Emmanuel II of Sardinia was proclaimed King of Italy—until 1946—when a constitutional referendum led civil discontent to abandon the monarchy and form the modern Italian Republic.
A klystron is a specialized linear-beam vacuum tube, invented in 1937 by American electrical engineers Russell and Sigurd Varian,Pond, Norman H. "The Tube Guys".
The Kriegsmarine (literally "War Navy") was the navy of Germany from 1935 to 1945.
Kronstadt (Кроншта́дт), also spelled Kronshtadt, Cronstadt or Kronštádt (Krone for "crown" and Stadt for "city"; Kroonlinn), is a municipal town in Kronshtadtsky District of the federal city of Saint Petersburg, Russia, located on Kotlin Island, west of Saint Petersburg proper near the head of the Gulf of Finland.
The Ku band is the portion of the electromagnetic spectrum in the microwave range of frequencies from 12 to 18 gigahertz (GHz).
Kwajalein Atoll (Marshallese: Kuwajleen) is part of the Republic of the Marshall Islands (RMI).
The L band is the Institute of Electrical and Electronics Engineers (IEEE) designation for the range of frequencies in the radio spectrum from 1 to 2 gigahertz (GHz).
A laser is a device that emits light through a process of optical amplification based on the stimulated emission of electromagnetic radiation.
Lawrence A. "Pat" Hyland (August 26, 1897 – November 24, 1989) was an American electrical engineer.
Leo C. Young (12 January 1891 – 16 January 1981) was an American radio engineer who had many accomplishments during a long career at the U.S. Naval Research Laboratory.
Lidar (also called LIDAR, LiDAR, and LADAR) is a surveying method that measures distance to a target by illuminating the target with pulsed laser light and measuring the reflected pulses with a sensor.
Light is electromagnetic radiation within a certain portion of the electromagnetic spectrum.
Lightning is a sudden electrostatic discharge that occurs typically during a thunderstorm.
Line-of-sight propagation is a characteristic of electromagnetic radiation or acoustic wave propagation which means waves travel in a direct path from the source to the receiver.
In electrodynamics, linear polarization or plane polarization of electromagnetic radiation is a confinement of the electric field vector or magnetic field vector to a given plane along the direction of propagation.
This is a list of radars.
This List of Ultra-wideband (UWB) Channels describes the physical bands and TFC codes defined in the WiMedia Alliance's PHY specification, as well as their link to the logical channels used in the higher layers such as the Wireless USB driver.
The Lockheed Martin F-22 Raptor is a fifth-generation, single-seat, twin-engine, all-weather stealth tactical fighter aircraft developed for the United States Air Force (USAF).
A radar system has look-down/shoot-down capability if it can detect, track and guide a weapon to an air target moving below the horizon as seen by the radar.
LORAN, short for long range navigation, was a hyperbolic radio navigation system developed in the United States during World War II.
Machine learning is a subset of artificial intelligence in the field of computer science that often uses statistical techniques to give computers the ability to "learn" (i.e., progressively improve performance on a specific task) with data, without being explicitly programmed.
Magnetism is a class of physical phenomena that are mediated by magnetic fields.
The FuMG 41/42 Mammut was a long-range, phased array, early warning radar built by Germany in the latter days of World War II.
Marine radars are X band or S band radars on ships, used to detect other ships and land obstacles, to provide bearing and distance for collision avoidance and navigation at sea.
In signal processing, a matched filter is obtained by correlating a known signal, or template, with an unknown signal to detect the presence of the template in the unknown signal.
A meteoroid is a small rocky or metallic body in outer space.
Meteorology is a branch of the atmospheric sciences which includes atmospheric chemistry and atmospheric physics, with a major focus on weather forecasting.
The metre (British spelling and BIPM spelling) or meter (American spelling) (from the French unit mètre, from the Greek noun μέτρον, "measure") is the base unit of length in some metric systems, including the International System of Units (SI).
Microwaves are a form of electromagnetic radiation with wavelengths ranging from one meter to one millimeter; with frequencies between and.
The Mikoyan MiG-31 (Микоян МиГ-31; NATO reporting name: Foxhound) is a supersonic interceptor aircraft developed for use by the Soviet Air Forces.
A military or armed force is a professional organization formally authorized by a sovereign state to use lethal or deadly force and weapons to support the interests of the state.
The millimetre (International spelling as used by the International Bureau of Weights and Measures; SI unit symbol mm) or millimeter (American spelling) is a unit of length in the metric system, equal to one thousandth of a metre, which is the SI base unit of length.
The MIM-104 Patriot is a surface-to-air missile (SAM) system, the primary of its kind used by the United States Army and several allied nations.
A mirror is an object that reflects light in such a way that, for incident light in some range of wavelengths, the reflected light preserves many or most of the detailed physical characteristics of the original light, called specular reflection.
In modern language, a missile is a guided self-propelled system, as opposed to an unguided self-propelled munition, referred to as a rocket (although these too can also be guided).
MISTRAM (MISsile TRAjectory Measurement) was a high-resolution tracking system used by the United States Air Force (and later NASA) to provide highly detailed trajectory analysis of rocket launches.
The Radiation Laboratory, commonly called the Rad Lab, was a microwave and radar research laboratory located at the Massachusetts Institute of Technology (MIT) in Cambridge, Massachusetts (US).
In electronics and telecommunications, modulation is the process of varying one or more properties of a periodic waveform, called the carrier signal, with a modulating signal that typically contains information to be transmitted.
Monopulse radar is a radar system that implements the monopulse method for estimating the direction to the radar target.
The Moon is an astronomical body that orbits planet Earth and is Earth's only permanent natural satellite.
A motion detector is a device that detects moving objects, particularly people.
A motor vehicle is a self-propelled vehicle, commonly wheeled, that does not operate on rails, such as trains or trams and used for the transportation of passengers, or passengers and property.
Moving target indication (MTI) is a mode of operation of a radar to discriminate a target against the clutter.
In wireless telecommunications, multipath is the propagation phenomenon that results in radio signals reaching the receiving antenna by two or more paths.
Nap-of-the-earth (abbreviated NOE) is a type of very low-altitude flight course used by military aircraft to avoid enemy detection and attack in a high-threat environment.
The National Severe Storms Laboratory (NSSL) is a National Oceanic and Atmospheric Administration (NOAA) weather research laboratory under the Office of Oceanic and Atmospheric Research.
A nautical mile is a unit of measurement defined as exactly.
Nazi Germany is the common English name for the period in German history from 1933 to 1945, when Germany was under the dictatorship of Adolf Hitler through the Nazi Party (NSDAP).
The nearest neighbour algorithm was one of the first algorithms used to determine a solution to the travelling salesman problem.
The Netherlands (Nederland), often referred to as Holland, is a country located mostly in Western Europe with a population of seventeen million.
New Zealand (Aotearoa) is a sovereign island country in the southwestern Pacific Ocean.
NEXRAD or Nexrad (Next-Generation Radar) is a network of 159 high-resolution S-band Doppler weather radars operated by the National Weather Service (NWS), an agency of the National Oceanic and Atmospheric Administration (NOAA) within the United States Department of Commerce, the Federal Aviation Administration (FAA) within the Department of Transportation, and the U.S. Air Force within the Department of Defense.
In electronics, noise is an unwanted disturbance in an electrical signal.
Noise figure (NF) and noise factor (F) are measures of degradation of the signal-to-noise ratio (SNR), caused by components in a signal chain.
In signal theory, the noise floor is the measure of the signal created from the sum of all the noise sources and unwanted signals within a measurement system, where noise is defined as any signal other than the one being monitored.
The Nyquist frequency, named after electronic engineer Harry Nyquist, is half of the sampling rate of a discrete signal processing system.
Oboe was a British aerial blind bombing targeting system in World War II, based on radio transponder technology.
In radio communication, an omnidirectional antenna is a class of antenna which have an axis about which radio wave power is radiated symmetrically, and, upon that axis, is zero.
Omniview technology (also known as "surround view" or "bird view technology") is a vehicle parking assistant technology that first became available in vehicle electronic products in 2007.
Optical resolution describes the ability of an imaging system to resolve detail in the object that is being imaged.
Over-the-horizon radar, or OTH (sometimes called beyond the horizon, or BTH), is a type of radar system with the ability to detect targets at very long ranges, typically hundreds to thousands of kilometres, beyond the radar horizon, which is the distance limit for ordinary radar.
In mathematics, a parabola is a plane curve which is mirror-symmetrical and is approximately U-shaped.
A passive electronically scanned array (PESA), also known as passive phased array, is a phased array antenna, that is an antenna in which the beam of radio waves can be electronically steered to point in different directions, in which all the antenna elements are connected to a single transmitter (such as a magnetron, a klystron or a travelling wave tube) and/or receiver.
Path loss (or path attenuation) is the reduction in power density (attenuation) of an electromagnetic wave as it propagates through space.
The Pathfinders were target-marking squadrons in RAF Bomber Command during World War II.
Pavel Kondratyevich Oshchepkov (June 24, 1908 – December 1, 1992) was a Russian physicist who had a leading role in the development of radio-location (radar) in the USSR.
The Petlyakov Pe-2 (Петляков Пе-2) was a Soviet light bomber used during World War II.
In antenna theory, a phased array usually means an electronically scanned array; a computer-controlled array of antennas which creates a beam of radio waves which can be electronically steered to point in different directions, without moving the antennas.
The plan position indicator (PPI), is the most common type of radar display.
Polarization (also polarisation) is a property applying to transverse waves that specifies the geometrical orientation of the oscillations.
Pollution prevention (P2) reduces the amount of pollution generated by industries, agriculture, or consumers.
Popular Science (also known as PopSci) is an American quarterly magazine carrying popular science content, which refers to articles for the general reader on science and technology subjects.
The Potomac River is located within the Mid-Atlantic region of the United States and flows from the Potomac Highlands into the Chesapeake Bay.
In meteorology, precipitation is any product of the condensation of atmospheric water vapor that falls under gravity.
A precision-guided munition (PGM, smart weapon, smart munition, smart bomb) is a guided munition intended to precisely hit a specific target, to minimize collateral damage and increase lethality against intended targets.
A Primary radar (PSR Primary Surveillance Radar) is a conventional radar sensor that illuminates a large portion of space with an electromagnetic wave and receives back the reflected waves from targets within that space.
The probabilistic data association filter (PDAF) is a statistical approach to the problem of plot association in a radar tracker, in which all of the potential candidates for association to a track are combined in a single statistically most probable update, taking account of the statistical distribution of the track errors and clutter and assuming that only one of the candidates is a target, and the rest are false alarms.
A proximity fuze is a fuze that detonates an explosive device automatically when the distance to the target becomes smaller than a predetermined value.
Public health surveillance (also epidemiological surveillance, clinical surveillance or syndromic surveillance) is, according to the World Health Organization (WHO), "the continuous, systematic collection, analysis and interpretation of health-related data needed for the planning, implementation, and evaluation of public health practice.", World Health Organization (accessed January 14, 2016).
Pulse compression is a signal processing technique commonly used by radar, sonar and echography to increase the range resolution as well as the signal to noise ratio.
A pulse forming network (PFN) is an electric circuit that accumulates electrical energy over a comparatively long time, then releases the stored energy in the form of a relatively square pulse of comparatively brief duration for various pulsed power applications.
The pulse repetition frequency (PRF) is the number of pulses of a repeating signal in a specific time unit, normally measured in pulses per second.
A pulse-Doppler radar is a radar system that determines the range to a target using pulse-timing techniques, and uses the Doppler effect of the returned signal to determine the target object's velocity.
Pulse-Doppler signal processing is a radar and CEUS performance enhancement strategy that allows small high-speed objects to be detected in close proximity to large slow moving objects.
Pulsed power is the science and technology of accumulating energy over a relatively long period of time and releasing it very quickly, thus increasing the instantaneous power.
A radar altimeter, electronic altimeter, reflection altimeter, radio altimeter (RADALT), low range radio altimeter (LRRA) or simply RA, used on aircraft, measures altitude above the terrain presently beneath an aircraft or spacecraft by timing how long it takes a beam of radio waves to reflect from the ground and return to the plane.
Radar astronomy is a technique of observing nearby astronomical objects by reflecting microwaves off target objects and analyzing the reflections.
Radar cross-section (RCS) is a measure of how detectable an object is by radar.
A radar display is an electronic device to present radar data to the operator.
Radar engineering details are technical details pertaining to the components of a radar and their ability to detect the return energy from moving scatterers — determining an object's position or obstruction in the environment.
A radar speed gun (also radar gun and speed gun) is a device used to measure the speed of moving objects.
The radar horizon is a critical area of performance for aircraft detection systems that is defined by the distance at which the radar beam rises enough above the Earth's surface to make detection of a target at low level impossible.
Marine and aviation radar systems can provide very useful navigation information in a variety of situations.
A radar tower is a tower whose function is to support a radar facility, usually a local airport surveillance radar, and hence often at or in the vicinity of an airport or a military air base.
A radar tracker is a component of a radar system, or an associated command and control (C2) system, that associates consecutive radar observations of the same target into tracks.
Radiation-absorbent material, usually known as RAM, is a material which has been specially designed and shaped to absorb incident RF radiation (also known as non-ionising radiation), as effectively as possible, from as many incident directions as possible.
Radio is the technology of using radio waves to carry information, such as sound, by systematically modulating properties of electromagnetic energy waves transmitted through space, such as their amplitude, frequency, phase, or pulse width.
Radio astronomy is a subfield of astronomy that studies celestial objects at radio frequencies.
In radio communications, a radio receiver (receiver or simply radio) is an electronic device that receives radio waves and converts the information carried by them to a usable form.
The radio spectrum is the part of the electromagnetic spectrum with frequencies from 3 Hz to 3 000 GHz (3 THz).
Radio waves are a type of electromagnetic radiation with wavelengths in the electromagnetic spectrum longer than infrared light.
Radiodetermination service is – according to Article 1.40 of the International Telecommunication Union´s (ITU) Radio Regulations (RR) – defined as «A radiocommunication service for the purpose of radiodetermination.»;See also.
Radiolocation service (short: RLS) is – according to Article 1.48 of the International Telecommunication Union´s (ITU) Radio Regulations (RR) – defined as «A radiodetermination service for the purpose of radiolocation.»;See also.
Radiolocation-satellite service (short: RLSS) is – according to Article 1.49 of the International Telecommunication Union´s (ITU) Radio Regulations (RR) – defined as «A radiodetermination-satellite service used for the purpose of radiolocation.
Range ambiguity resolution is a technique used with medium Pulse repetition frequency (PRF) radar to obtain range information for distances that exceed the distance between transmit pulses.
A rangefinder is a device that measures distance from the observer to a target, in a process called ranging.
Rayleigh scattering (pronounced), named after the British physicist Lord Rayleigh (John William Strutt), is the (dominantly) elastic scattering of light or other electromagnetic radiation by particles much smaller than the wavelength of the radiation.
Reflection is the change in direction of a wavefront at an interface between two different media so that the wavefront returns into the medium from which it originated.
Refraction is the change in direction of wave propagation due to a change in its transmission medium.
In optics, the refractive index or index of refraction of a material is a dimensionless number that describes how light propagates through that medium.
The relative permittivity of a material is its (absolute) permittivity expressed as a ratio relative to the permittivity of vacuum.
A research vessel (RV or R/V) is a ship or boat designed, modified, or equipped to carry out research at sea.
In physics, resonance is a phenomenon in which a vibrating system or external force drives another system to oscillate with greater amplitude at specific frequencies.
In geometry and trigonometry, a right angle is an angle of exactly 90° (degrees), corresponding to a quarter turn.
Robert Morris Page (2 June 1903 – 15 May 1992) was an American physicist who was a leading figure in the development of radar technology.
Sir Robert Alexander Watson-Watt, KCB, FRS, FRAeS (13 April 1892 – 5 December 1973) was a Scottish pioneer of radio direction finding and radar technology.
The Rockwell B-1 LancerThe name "Lancer" is only applied to the B-1B version, after the program was revived.
The Ronald Reagan Ballistic Missile Defense Test Site, commonly referred to as the Reagan Test Site (formerly Kwajalein Missile Range), is a missile test range in Marshall Islands (Pacific Ocean).
A rotation is a circular movement of an object around a center (or point) of rotation.
Rotterdam is a city in the Netherlands, in South Holland within the Rhine–Meuse–Scheldt river delta at the North Sea.
Rudolf Kühnhold (1903–1992) was an experimental physicist who is often given credit for initiating research that led to the Funkmessgerät (radio measuring device – radar) in Germany.
The S band is a designation by the Institute of Electrical and Electronics Engineers (IEEE) for a part of the microwave band of the electromagnetic spectrum covering frequencies from 2 to 4 gigahertz (GHz).
The Safeguard Program was a U.S. Army anti-ballistic missile (ABM) system designed to protect the U.S. Air Force's Minuteman ICBM silos from attack, thus preserving the US's nuclear deterrent fleet.
Saint Petersburg Electrotechnical University "LETI" (Санкт-Петербургский государственный электротехнический университет «ЛЭТИ» им. В.И. Ульянова (Ленина)) founded in 1886, and is one of the oldest higher education institutions in Saint Petersburg.
Scattering is a general physical process where some forms of radiation, such as light, sound, or moving particles, are forced to deviate from a straight trajectory by one or more paths due to localized non-uniformities in the medium through which they pass.
The SCR-270 (Signal Corps Radio model 270) was one of the first operational early-warning radars.
A searchlight (or spotlight) is an apparatus that combines an extremely luminous source (traditionally a carbon arc lamp) with a mirrored parabolic reflector to project a powerful beam of light of approximately parallel rays in a particular direction, usually constructed so that it can be swiveled about.
Seawater, or salt water, is water from a sea or ocean.
Secondary surveillance radar (SSR)Secondary Surveillance Radar, Stevens M.C. Artech House, is a radar system used in air traffic control (ATC), that not only detects and measures the position of aircraft, i.e. bearing and distance, but also requests additional information from the aircraft itself such as its identity and altitude.
Semi-active radar homing (SARH) is a common type of missile guidance system, perhaps the most common type for longer-range air-to-air and surface-to-air missile systems.
Sensitivity time control (STC) is used to attenuate the very strong signals returned from nearby ground clutter targets in the first few range gates of a Radar receiver.
Severe weather refers to any dangerous meteorological phenomena with the potential to cause damage, serious social disruption, or loss of human life.
Shortwave radio is radio transmission using shortwave radio frequencies.
Shot noise or Poisson noise is a type of electronic noise which can be modeled by a Poisson process.
In antenna engineering, side lobes or sidelobes are the lobes (local maxima) of the far field radiation pattern that are not the main lobe.
Signal processing concerns the analysis, synthesis, and modification of signals, which are broadly defined as functions conveying "information about the behavior or attributes of some phenomenon", such as sound, images, and biological measurements.
Signal-to-noise ratio (abbreviated SNR or S/N) is a measure used in science and engineering that compares the level of a desired signal to the level of background noise.
In chemistry, a silicate is any member of a family of anions consisting of silicon and oxygen, usually with the general formula, where 0 ≤ x Silicate anions are often large polymeric molecules with an extense variety of structures, including chains and rings (as in polymeric metasilicate), double chains (as in, and sheets (as in. In geology and astronomy, the term silicate is used to mean silicate minerals, ionic solids with silicate anions; as well as rock types that consist predominantly of such minerals. In that context, the term also includes the non-ionic compound silicon dioxide (silica, quartz), which would correspond to x.
A sine wave or sinusoid is a mathematical curve that describes a smooth periodic oscillation.
In radio communication, skywave or skip refers to the propagation of radio waves reflected or refracted back toward Earth from the ionosphere, an electrically charged layer of the upper atmosphere.
The slide rule, also known colloquially in the United States as a slipstick, is a mechanical analog computer.
In geometry, a solid angle (symbol) is a measure of the amount of the field of view from some particular point that a given object covers.
Sonar (originally an acronym for SOund Navigation And Ranging) is a technique that uses sound propagation (usually underwater, as in submarine navigation) to navigate, communicate with or detect objects on or under the surface of the water, such as other vessels.
South Africa, officially the Republic of South Africa (RSA), is the southernmost country in Africa.
The Soviet Union, officially the Union of Soviet Socialist Republics (USSR) was a socialist state in Eurasia that existed from 1922 to 1991.
A space rendezvous is an orbital maneuver during which two spacecraft, one of which is often a space station, arrive at the same orbit and approach to a very close distance (e.g. within visual contact).
Space surveillance is the study and monitoring of satellites orbiting the earth.
Space-time adaptive processing (STAP) is a signal processing technique most commonly used in radar systems.
A spacecraft is a vehicle or machine designed to fly in outer space.
A spark-gap transmitter is a device that generates radio frequency electromagnetic waves using a spark gap.
A spectrum analyzer measures the magnitude of an input signal versus frequency within the full frequency range of the instrument.
In everyday use and in kinematics, the speed of an object is the magnitude of its velocity (the rate of change of its position); it is thus a scalar quantity.
The speed of light in vacuum, commonly denoted, is a universal physical constant important in many areas of physics.
The SS Normandie was an ocean liner built in Saint-Nazaire, France, for the French Line Compagnie Générale Transatlantique (CGT).
Stealth aircraft are designed to avoid detection using a variety of technologies that reduce reflection/emission of radar, infrared, visible light, radio-frequency (RF) spectrum, and audio, collectively known as stealth technology.
Stealth technology also termed low observable technology (LO technology) is a sub-discipline of military tactics and passive electronic countermeasures, which cover a range of techniques used with personnel, aircraft, ships, submarines, missiles and satellites to make them less visible (ideally invisible) to radar, infrared, sonar and other detection methods.
The Sun is the star at the center of the Solar System.
Sunset or sundown is the daily disappearance of the Sun below the horizon as a result of Earth's rotation.
Surveillance is the monitoring of behavior, activities, or other changing information for the purpose of influencing, managing, directing, or protecting people.
Synthetic-aperture radar (SAR) is a form of radar that is used to create two- or three-dimensional images of objects, such as landscapes.
Terrain-following radar (TFR) is an aerospace technology that allows a very-low-flying aircraft to automatically maintain a relatively constant altitude above ground level.
The thinned array curse (sometimes, sparse array curse) is a theorem in electromagnetic theory of antennas.
Thomson-CSF was a major electronics and defence contractor.
A thunderstorm, also known as an electrical storm, lightning storm, or thundershower, is a storm characterized by the presence of lightning and its acoustic effect on the Earth's atmosphere, known as thunder.
A thyratron is a type of gas-filled tube used as a high-power electrical switch and controlled rectifier.
Time of flight (TOF) is a property of an object, particle or acoustic, electromagnetic or other wave.
In signal processing, time–frequency analysis comprises those techniques that study a signal in both the time and frequency domains simultaneously, using various time–frequency representations.
The Tizard Mission, officially the British Technical and Scientific Mission, was a British delegation that visited the United States during the Second World War in order to obtain the industrial resources to exploit the military potential of the research and development (R&D) work completed by the UK up to the beginning of World War II, but that Britain itself could not exploit due to the immediate requirements of war-related production.
A tornado is a rapidly rotating column of air that is in contact with both the surface of the Earth and a cumulonimbus cloud or, in rare cases, the base of a cumulus cloud.
In radar technology and similar fields, track-before-detect (TBD) is a concept according to which a signal is tracked before declaring it a target.
In electronics and telecommunications, a transmitter or radio transmitter is an electronic device which produces radio waves with an antenna.
A transponder (short for transmitter-responder and sometimes abbreviated to XPDR, XPNDR, TPDR or TP) is an electronic device that produces a response when it receives a radio-frequency interrogation.
A traveling-wave tube (TWT, pronounced "twit") or traveling-wave tube amplifier (TWTA, pronounced "tweeta") is a specialized vacuum tube that is used in electronics to amplify radio frequency (RF) signals in the microwave range.
In fluid dynamics, turbulence or turbulent flow is any pattern of fluid motion characterized by chaotic changes in pressure and flow velocity.
The UDOP (UHF Doppler) multistatic radar and multiradar system (MSRS) utilizes Doppler radar for missile tracking and trajectory measurement.
Ultra high frequency (UHF) is the ITU designation for radio frequencies in the range between 300 megahertz (MHz) and 3 gigahertz (GHz), also known as the decimetre band as the wavelengths range from one meter to one decimeter.
Ultra-wideband (also known as UWB, ultra-wide band and ultraband) is a radio technology that can use a very low energy level for short-range, high-bandwidth communications over a large portion of the radio spectrum.
Ultraviolet (UV) is electromagnetic radiation with a wavelength from 10 nm to 400 nm, shorter than that of visible light but longer than X-rays.
United Airlines, Inc., commonly referred to as United, is a major United States airline headquartered in Chicago, Illinois.
The United Kingdom of Great Britain and Northern Ireland, commonly known as the United Kingdom (UK) or Britain,Usage is mixed with some organisations, including the and preferring to use Britain as shorthand for Great Britain is a sovereign country in western Europe.
The United States of America (USA), commonly known as the United States (U.S.) or America, is a federal republic composed of 50 states, a federal district, five major self-governing territories, and various possessions.
The United States Army (USA) is the land warfare service branch of the United States Armed Forces.
The United States Naval Research Laboratory (NRL) is the corporate research laboratory for the United States Navy and the United States Marine Corps.
The United States Navy (USN) is the naval warfare service branch of the United States Armed Forces and one of the seven uniformed services of the United States.
The V band ("vee-band") is a standard designation by the Institute of Electrical and Electronic Engineers (IEEE) for a band of frequencies in the microwave portion of the electromagnetic spectrum ranging from 40 to 75 gigahertz (GHz).
Vacuum is space devoid of matter.
Very high frequency (VHF) is the ITU designation for the range of radio frequency electromagnetic waves (radio waves) from 30 to 300 megahertz (MHz), with corresponding wavelengths of ten to one meter.
A vessel traffic service (VTS) is a marine traffic monitoring system established by harbour or port authorities, similar to air traffic control for aircraft.
The W band of the microwave part of the electromagnetic spectrum ranges from 75 to 110 GHz, wavelength ≈2.7–4 mm.
Wind waves can be measured by several radar remote sensing techniques.
A waveguide is a structure that guides waves, such as electromagnetic waves or sound, with minimal loss of energy by restricting expansion to one dimension or two.
A wavelet is a wave-like oscillation with an amplitude that begins at zero, increases, and then decreases back to zero.
Weather is the state of the atmosphere, describing for example the degree to which it is hot or cold, wet or dry, calm or stormy, clear or cloudy.
Weather forecasting is the application of science and technology to predict the conditions of the atmosphere for a given location and time.
Weather radar, also called weather surveillance radar (WSR) and Doppler weather radar, is a type of radar used to locate precipitation, calculate its motion, and estimate its type (rain, snow, hail etc.). Modern weather radars are mostly pulse-Doppler radars, capable of detecting the motion of rain droplets in addition to the intensity of the precipitation.
A winter storm is an event in which varieties of precipitation are formed that only occur at low temperatures, such as snow or sleet, or a rainstorm where ground temperatures are low enough to allow ice to form (i.e. freezing rain).
World War II (often abbreviated to WWII or WW2), also known as the Second World War, was a global war that lasted from 1939 to 1945, although conflicts reflecting the ideological clash between what would become the Allied and Axis blocs began earlier.
The X band is the designation for a band of frequencies in the microwave radio region of the electromagnetic spectrum.
The Russian (former USSR) BRLS-8B "Zaslon" (Barrier) is an all-weather multimode airborne radar developed between 1975 and 1980 by the Tikhomirov Scientific Research Institute of Instrument Design as part of the weapons control system of the MiG-31 supersonic interceptor.
Air search radar, Airport radar, Centimetric radar, Microwave radar, RADAR, Radar Homing and Warning, Radar communication, Radar distance measurement, Radar equation, Radar illumination, Radar mile, Radar station, Radar system, Radar systems, Radars, Radio Detection and Ranging, Radio detecting and ranging, Radio detection and ranging, Remote Radar Head.