Fast Fourier Transform Telescope

This technique is already being used in radar applications. This paper refers to an earlier telescope design from 1993 which took direct images of the Crab nebula at radio wavelengths using an eight-by-eight-pixel two-dimensional spatial FFT processor. Aperture synthesis. Interferometric synthetic aperture radar. Inverse synthetic aperture radar. List of telescope types. Synthetic aperture radar. Jan Hamann, Steen Hannestad, Martin S. Sloth, Yvonne Y. Y. Wong (2008), "Observing trans-Planckian ripples in the primordial power spectrum with future large scale structure probes", Journal of Cosmology and Astroparticle Physics, arxiv 0807.4528. Jonathan R.

Weather radar

Doppler weather radarradarDoppler radar
Thus 10 cm (S-band) radar is preferred but is more expensive than a 5 cm C-band system. 3 cm X-band radar is used only for short-range units, and 1 cm Ka-band weather radar is used only for research on small-particle phenomena such as drizzle and fog. W band weather radar systems have seen limited university use, but due to quicker attenuation, most data are not operational. Radar pulses spread out as they move away from the radar station. Thus the volume of air that a radar pulse is traversing is larger for areas farther away from the station, and smaller for nearby areas, decreasing resolution at far distances.


Just as the words laser and radar function as words in syntax and cognition without a need to focus on their acronymic origins, terms such as "RARS" and "CHA2DS2–VASc score" are irreducible in natural language; if they are purged, the form of language that is left may conform to some imposed rule, but it cannot be described as remaining natural.


microwavesmicrowave radiationmicrowave tube
Microwave radar is widely used for applications such as air traffic control, weather forecasting, navigation of ships, and speed limit enforcement. Long distance radars use the lower microwave frequencies since at the upper end of the band atmospheric absorption limits the range, but millimeter waves are used for short range radar such as collision avoidance systems. Microwaves emitted by astronomical radio sources; planets, stars, galaxies, and nebulas are studied in radio astronomy with large dish antennas called radio telescopes.

Marine radar

marine search radarRadar Surveillanceradar systems
Radar in the 21st Century.


radio transmittertransmittersradio transmitters
Transmitters are necessary component parts of all electronic devices that communicate by radio, such as radio and television broadcasting stations, cell phones, walkie-talkies, wireless computer networks, Bluetooth enabled devices, garage door openers, two-way radios in aircraft, ships, spacecraft, radar sets and navigational beacons. The term transmitter is usually limited to equipment that generates radio waves for communication purposes; or radiolocation, such as radar and navigational transmitters.

Radar astronomy

radarRadar observationsradar telescope


laser altimeterLight Detection and Ranging3D laser scanning
In addition to the lidar detection, RADAR data obtained by using two short-range radars is integrated to get additional dynamic properties of the object, such as its velocity. The measurements are assigned to the object using a potential distance function. ; Advantages and disadvantages The geometric features of the objects are extracted efficiently, from the measurements obtained by the 3-D occupancy grid, using rotating caliper algorithm.

3D reconstruction

3D imagingreconstruction3D mapping
Digital elevation models can be reconstructed using methods such as airborne laser altimetry or synthetic aperture radar. Active methods, i.e. range data methods, given the depth map, reconstruct the 3D profile by numerical approximation approach and build the object in scenario based on model. These methods actively interfere with the reconstructed object, either mechanically or radiometrically using rangefinders, in order to acquire the depth map, e.g. structured light, laser range finder and other active sensing techniques. A simple example of a mechanical method would use a depth gauge to measure a distance to a rotating object put on a turntable.

Close-in weapon system

CIWSclose-in weapons systemclose in weapon system
A gun-based CIWS usually consists of a combination of radars, computers, and rapid-firing multiple-barrel rotary cannons placed on a rotating turret. Missile-based CIWSs use infra-red, passive radar/ESM or semi-active radar terminal guidance to guide missiles to the targeted enemy aircraft or other threats. In some cases, CIWS are used on land to protect military bases. In this case, the CIWS can also protect the base from shell and rocket fire. A gun-based CIWS usually consists of a combination of radars, computers and rotary or revolver cannon placed on a rotating, automatically-aimed gun mount.

Digital signal processing

DSPsignal processingdigital
Applications of DSP include audio signal processing, audio compression, digital image processing, video compression, speech processing, speech recognition, digital communications, digital synthesizers, radar, sonar, financial signal processing, seismology and biomedicine.

Christian Hülsmeyer

Although there is controversy about his inventing radar, Christian Hülsmeyer is still held in high esteem in Germany. In January 1982, Professor K. Mauel gave a lecture at the Organization of German Engineers Center in Düsseldorf on Radar History, celebrating the centenary of Hülsmeyer’s birth. At the 2002 EUSAR Conference in Cologne, the keynote speech was "Hülsmeyer – The Inventor of Radar." During a radar conference held in Frankfurt in 1953, Hülsmeyer and Robert Watson-Watt were honored guests. (Watson-Watt had been a leader of radar technology development in Great Britain, and received a patent on the system in 1935).

Direction finding

radio direction findingradio direction-findingdirection-finding
Early British radar sets were referred to as RDF, which is often stated was a deception. In fact, the Chain Home systems used large RDF receivers to determine directions. Later radar systems generally used a single antenna for broadcast and reception, and determined direction from the direction the antenna was facing. Direction finding requires an antenna that is directional (more sensitive in certain directions than in others). Many antenna designs exhibit this property. For example, a Yagi antenna has quite pronounced directionality, so the source of a transmission can be determined simply by pointing it in the direction where the maximum signal level is obtained.

Robert Watson-Watt

Robert Watson WattRobert WattRobert Alexander Watson-Watt
Deflating British Radar Myths of World War II A comparison of contemporary British and German radar inventions and their use. Radar Development In England. Sir Robert Alexander Watson-Watt's biography. The Robert Watson-Watt Society.

Arnold Wilkins

Arnold Frederic WilkinsArnold "Skip" WilkinsArnold F. 'Skip' Wilkins
History of radar. Aeronautical Research Committee (Tizard Committee).

Inverse synthetic-aperture radar

Inverse synthetic aperture radarinverse SARISAR
Synthetic-aperture radar. Aperture synthesis. Beamforming. Phased array. Optical heterodyne detection. Inverse Synthetic Aperture Imaging Radar by Dan Slater 1985. Inverse Synthetic Aperture Imaging Radar by Dan Slater 1985. 2D and 3D UWB Radar Imaging systems developed in Geozondas. Advanced Radar Systems.

Lawrence A. Hyland

Hyland, Lawrence A.L.A. "Pat" Hyland
He is one of three individuals, with whom are credited in major contributions to the invention of radar, but is probably best known as the man who transformed Hughes Aircraft from Howard Hughes' aviation "hobby shop" into one of the world's leading technology companies. Hyland was born in Nova Scotia, Canada, but his family moved to the U.S. in 1899, where he was raised in Massachusetts. He served in the U.S. Army during World War I, and then in the U.S. Navy until 1926. Hyland then joined the U.S. Naval Research Laboratory as a radio engineer.

Robert Morris Page

Robert M. Page
When the high-power cavity magnetron from Great Britain was introduced into America by the Tizard Mission in 1940, Page turned his attention to microwave radar and, working with the MIT Radiation Laboratory and the Bell Telephone Laboratories, made invaluable contributions to this new technology. One of the most significant was a system that greatly improved the angular accuracy of tracking radars. Called monopulse radar, it was first demonstrated in 1943. This highly complex technology was later used in the AN/FPS-16, likely the most popular tracking radar in history.

Albert H. Taylor

A. Hoyt TaylorAlbert Hoyt TaylorA. H. Taylor
By 1937, his team had developed a practical shipboard radar that became known as CXAM radar, a technology very similar to that of Britain's Chain Home radar system. In 1929 Taylor was President of the Institute of Radio Engineers (IRE), and from 1936 to 1942 he served on the Communication Committee of the American Institute of Electrical Engineers. Both of these organizations were predecessors to what is now the IEEE. Taylor remained at NRL until his retirement in 1948.

Pavel K. Oshchepkov

P.K. Oshchepkov
Vovshin; “Radar in the Soviet Union and Russia: A Brief Historical Outline,” IEEE AES Magazine, Vol. 19, December, p. 8, 2003. Erickson, John; “Radio-location and the air defense problem: The design and development of Soviet Radar 1934-40,” Social Studies of Science, Vol. 2, p. 241, 1972. Kostenko, A. A., A. I. Nosich., and I. A. Tishchenko; “Radar Prehistory, Soviet Side,” Proceedings of IEEE APS International Symposium 2001, Vol. 4, p. 44, 2002. Siddiqi, Asif A.; “Rockets Red Glare: Technology, Conflict, and Terror in the Soviet Union," Technology & Culture, Vol. 44, p. 470, 2003. Watson, Raymond C., Jr.; Radar Origins Worldwide, Trafford Publishing, 2009.

Chain Home

Daventry Experimentearly warning Chain Home radar system
RAF Bawdsey Chain Home Radar Station at Subterranean Britain. RAF Radar Museum. RAF High Street picture. Life at Darsham – BBC. Great Baddow Chain Home Mast & Radar Anniversary. Early radar development in the UK. 60 (Signals) Group, Fighter Command (pdf).

Antenna (radio)

antennaantennasradio antenna
These can be used to give the antenna a different behavior on receiving than it has on transmitting, which can be useful in applications like radar. The majority of antenna designs are based on the resonance principle. This relies on the behaviour of moving electrons, which reflect off surfaces where the dielectric constant changes, in a fashion similar to the way light reflects when optical properties change. In these designs, the reflective surface is created by the end of a conductor, normally a thin metal wire or rod, which in the simplest case has a feed point at one end where it is connected to a transmission line.

MIT Radiation Laboratory

Radiation LaboratoryRadiation LabMIT Radiation Lab
Among their notable products were the SCR-584, the finest gun-laying radar of the war, and the SCR-720, an airborne interception radar that became the standard late-war system for both US and UK night fighters. They also developed the H2X, a version of the British H2S bombing radar that operated at shorter wavelengths in the X band. The Rad Lab also developed Loran-A, the first worldwide radio navigation system, which originally was known as "LRN" for Loomis Radio Navigation.

Monopulse radar

monopulsemonopulse technique
Monopulse radar is a radar system that uses additional encoding of the radio signal to provide accurate directional information. The name refers to its ability to extract range and direction from a single signal pulse. Monopulse radar avoids problems seen in conical scanning radar systems, which can be confused by rapid changes in signal strength. The system also makes jamming more difficult. Most radars designed since the 1960s are monopulse systems. The monopulse method is also used in passive systems, such as electronic support measures and radio astronomy. Monopulse radar systems can be constructed with reflector antennas, lens antennas or array antennas.

Space surveillance

space domain awarenessSpace surveillance and trackingtracking
The French GRAVES (Grand Réseau Adapté à la Veille Spatiale) bi-static radar-based space surveillance system deploy by French Air Force. The European Space Situational Awareness Programme with multiple assets in its Space Surveillance and Tracking Segment.