90 relations: Absolute value, Allies of World War II, Alternating current, Arnold Sommerfeld, Bell Labs, Boundary value problem, Bragg's law, Cartesian coordinate system, Cave, Cavity magnetron, Circular polarization, Coaxial, Cutoff frequency, Density, Dielectric, Digital delay line, Edward Mills Purcell, Electric current, Electrical impedance, Electrical resistivity and conductivity, Electromagnetic radiation, Electromagnetic spectrum, Extremely high frequency, Frequency, George Clark Southworth, Guided wave testing, Hans Bethe, Harry Boot, Helmholtz equation, Inverse-square law, J. J. Thomson, Jagadish Chandra Bose, Jeffrey Goldstone, John Randall (physicist), John Renshaw Carson, John William Strutt, 3rd Baron Rayleigh, Julian Schwinger, Ku band, Light, Light tube, Linear polarization, Lumped element model, Massachusetts Institute of Technology, Medical ultrasound, Microstrip, Microwave, Microwave oven, MIT Radiation Laboratory, Nathan Marcuvitz, Network analysis (electrical circuits), ..., Nondestructive testing, Ohm, Oliver Lodge, Optical fiber, Optics, Orthomode transducer, Permittivity, Peter Debye, Phasor, Photonic-crystal fiber, Polarization (waves), Power (physics), Pressure, Prism, Radar, Radio propagation, Radio wave, Reflection (physics), Refractive index, Relative permittivity, Robert H. Dicke, Robert Jaffe, Siemens & Halske, SOFAR channel, Sound, Standing wave ratio, Stethoscope, String instrument, String vibration, Stripline, Telecommunications Research Establishment, Total internal reflection, Transmission line, Transverse mode, Wave equation, Wave propagation, Whale vocalization, Wilmer L. Barrow, Wind instrument, World War II. Expand index (40 more) » « Shrink index
In mathematics, the absolute value or modulus of a real number is the non-negative value of without regard to its sign.
The Allies of World War II, called the United Nations from the 1 January 1942 declaration, were the countries that together opposed the Axis powers during the Second World War (1939–1945).
Alternating current (AC) is an electric current which periodically reverses direction, in contrast to direct current (DC) which flows only in one direction.
Arnold Johannes Wilhelm Sommerfeld, (5 December 1868 – 26 April 1951) was a German theoretical physicist who pioneered developments in atomic and quantum physics, and also educated and mentored a large number of students for the new era of theoretical physics.
Nokia Bell Labs (formerly named AT&T Bell Laboratories, Bell Telephone Laboratories and Bell Labs) is an American research and scientific development company, owned by Finnish company Nokia.
In mathematics, in the field of differential equations, a boundary value problem is a differential equation together with a set of additional constraints, called the boundary conditions.
In physics, Bragg's law, or Wulff–Bragg's condition, a special case of Laue diffraction, gives the angles for coherent and incoherent scattering from a crystal lattice.
A Cartesian coordinate system is a coordinate system that specifies each point uniquely in a plane by a pair of numerical coordinates, which are the signed distances to the point from two fixed perpendicular directed lines, measured in the same unit of length.
A cave is a hollow place in the ground, specifically a natural space large enough for a human to enter.
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).
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.
In geometry, coaxial means that two or more three-dimensional linear forms share a common axis.
In physics and electrical engineering, a cutoff frequency, corner frequency, or break frequency is a boundary in a system's frequency response at which energy flowing through the system begins to be reduced (attenuated or reflected) rather than passing through.
The density, or more precisely, the volumetric mass density, of a substance is its mass per unit volume.
A dielectric (or dielectric material) is an electrical insulator that can be polarized by an applied electric field.
A digital delay line is a discrete element in digital filter theory, which allows a signal to be delayed by a number of samples.
Edward Mills Purcell (August 30, 1912 – March 7, 1997) was an American physicist who shared the 1952 Nobel Prize for Physics for his independent discovery (published 1946) of nuclear magnetic resonance in liquids and in solids.
An electric current is a flow of electric charge.
Electrical impedance is the measure of the opposition that a circuit presents to a current when a voltage is applied.
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.
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).
Frequency is the number of occurrences of a repeating event per unit of time.
George Clark Southworth (August 24, 1890 – July 6, 1972), who published as G. C. Southworth, was a prominent American radio engineer best known for his role in the development of waveguides in the early 1930s.
Guided wave testing (GWT) is one of latest methods in the field of non-destructive evaluation.
Hans Albrecht Bethe (July 2, 1906 – March 6, 2005) was a German-American nuclear physicist who made important contributions to astrophysics, quantum electrodynamics and solid-state physics, and won the 1967 Nobel Prize in Physics for his work on the theory of stellar nucleosynthesis.
Henry Albert Howard "Harry" Boot (29 July 1917 – 8 February 1983) was an English physicist who with Sir John Randall and James Sayers developed the cavity magnetron, which was one of the keys to the Allied victory in the Second World War.
In mathematics & physics, the Helmholtz equation, named for Hermann von Helmholtz, is the partial differential equation where ∇2 is the Laplacian, k is the wavenumber, and A is the amplitude.
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.
Sir Joseph John Thomson (18 December 1856 – 30 August 1940) was an English physicist and Nobel Laureate in Physics, credited with the discovery and identification of the electron; and with the discovery of the first subatomic particle.
Sir Jagadish Chandra Bose, CSI, CIE, FRS (30 November 1858 – 23 November 1937), also spelled Jagdish and Jagadis, was a polymath, physicist, biologist, biophysicist, botanist and archaeologist, and an early writer of science fiction.
Jeffrey Goldstone (born 3 September 1933) is a British theoretical physicist and an emeritus physics faculty member at the MIT Center for Theoretical Physics.
Sir John Turton Randall, (23 March 1905 – 16 June 1984) was a British physicist and biophysicist, credited with radical improvement of the cavity magnetron, an essential component of centimetric wavelength radar, which was one of the keys to the Allied victory in the Second World War.
John Renshaw Carson (June 28, 1886 – October 31, 1940) was a noted transmission theorist for early communications systems.
John William Strutt, 3rd Baron Rayleigh, (12 November 1842 – 30 June 1919) was a physicist who, with William Ramsay, discovered argon, an achievement for which he earned the Nobel Prize for Physics in 1904.
Julian Seymour Schwinger (February 12, 1918 – July 16, 1994) was a Nobel Prize winning American theoretical physicist.
The Ku band is the portion of the electromagnetic spectrum in the microwave range of frequencies from 12 to 18 gigahertz (GHz).
Light is electromagnetic radiation within a certain portion of the electromagnetic spectrum.
Light tubes (also known as light pipes or tubular skylights) are physical structures used for transmitting or distributing natural or artificial light for the purpose of illumination, and are examples of optical waveguides.
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.
The lumped element model (also called lumped parameter model, or lumped component model) simplifies the description of the behaviour of spatially distributed physical systems into a topology consisting of discrete entities that approximate the behaviour of the distributed system under certain assumptions.
The Massachusetts Institute of Technology (MIT) is a private research university located in Cambridge, Massachusetts, United States.
Medical ultrasound (also known as diagnostic sonography or ultrasonography) is a diagnostic imaging technique based on the application of ultrasound.
Microstrip is a type of electrical transmission line which can be fabricated using printed circuit board technology, and is used to convey microwave-frequency signals.
Microwaves are a form of electromagnetic radiation with wavelengths ranging from one meter to one millimeter; with frequencies between and.
A microwave oven (also commonly referred to as a microwave) is an electric oven that heats and cooks food by exposing it to electromagnetic radiation in the microwave frequency range.
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).
Nathan Marcuvitz (born December 29, 1913 in Brooklyn, New York, d. February 14, 2010 in Naples, FL), was an American electrical engineer, physicist, and educator who worked in the fields of microwave and electromagnetic theory.
A network, in the context of electronics, is a collection of interconnected components.
Nondestructive testing or non-destructive testing (NDT) is a wide group of analysis techniques used in science and technology industry to evaluate the properties of a material, component or system without causing damage.
The ohm (symbol: Ω) is the SI derived unit of electrical resistance, named after German physicist Georg Simon Ohm.
Sir Oliver Joseph Lodge, (12 June 1851 – 22 August 1940) was a British physicist and writer involved in the development of, and holder of key patents for, radio.
An optical fiber or optical fibre is a flexible, transparent fiber made by drawing glass (silica) or plastic to a diameter slightly thicker than that of a human hair.
Optics is the branch of physics which involves the behaviour and properties of light, including its interactions with matter and the construction of instruments that use or detect it.
An orthomode transducer (OMT) is a waveguide component.
In electromagnetism, absolute permittivity, often simply called permittivity, usually denoted by the Greek letter ε (epsilon), is the measure of resistance that is encountered when forming an electric field in a particular medium.
Peter Joseph William Debye (March 24, 1884 – November 2, 1966) was a Dutch-American physicist and physical chemist, and Nobel laureate in Chemistry.
In physics and engineering, a phasor (a portmanteau of phase vector), is a complex number representing a sinusoidal function whose amplitude (A), angular frequency (ω), and initial phase (θ) are time-invariant.
Photonic-crystal fiber (PCF) is a new class of optical fiber based on the properties of photonic crystals.
Polarization (also polarisation) is a property applying to transverse waves that specifies the geometrical orientation of the oscillations.
In physics, power is the rate of doing work, the amount of energy transferred per unit time.
Pressure (symbol: p or P) is the force applied perpendicular to the surface of an object per unit area over which that force is distributed.
In optics, a prism is a transparent optical element with flat, polished surfaces that refract light.
Radar is an object-detection system that uses radio waves to determine the range, angle, or velocity of objects.
Radio propagation is the behavior of radio waves as they travel, or are propagated, from one point to another, or into various parts of the atmosphere.
Radio waves are a type of electromagnetic radiation with wavelengths in the electromagnetic spectrum longer than infrared light.
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.
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.
Robert Henry Dicke (May 6, 1916 – March 4, 1997) was an American physicist who made important contributions to the fields of astrophysics, atomic physics, cosmology and gravity.
Robert L. Jaffe (born May 23, 1946) is an American physicist and the Jane and Otto Morningstar Professor of Physics at the Massachusetts Institute of Technology (MIT).
Siemens & Halske AG (or Siemens-Halske) was a German electrical engineering company that later became part of Siemens.
Sound speed as a function of depth at a position north of Hawaii in the Pacific Ocean derived from the 2005 World Ocean Atlas. The SOFAR channel axis is at ca. 750-m depth The SOFAR channel (short for Sound Fixing and Ranging channel), or deep sound channel (DSC), is a horizontal layer of water in the ocean at which depth the speed of sound is at its minimum.
In physics, sound is a vibration that typically propagates as an audible wave of pressure, through a transmission medium such as a gas, liquid or solid.
In radio engineering and telecommunications, standing wave ratio (SWR) is a measure of impedance matching of loads to the characteristic impedance of a transmission line or waveguide.
The stethoscope is an acoustic medical device for auscultation, or listening to the internal sounds of an animal or human body.
String instruments, stringed instruments, or chordophones are musical instruments that produce sound from vibrating strings when the performer plays or sounds the strings in some manner.
A vibration in a string is a wave.
Stripline is a transverse electromagnetic (TEM) transmission line medium invented by Robert M. Barrett of the Air Force Cambridge Research Centre in the 1950s.
The Telecommunications Research Establishment (TRE) was the main United Kingdom research and development organization for radio navigation, radar, infra-red detection for heat seeking missiles, and related work for the Royal Air Force (RAF) during World War II and the years that followed.
Total internal reflection is the phenomenon which occurs when a propagated wave strikes a medium boundary at an angle larger than a particular critical angle with respect to the normal to the surface.
In communications and electronic engineering, a transmission line is a specialized cable or other structure designed to conduct alternating current of radio frequency, that is, currents with a frequency high enough that their wave nature must be taken into account.
A transverse mode of electromagnetic radiation is a particular electromagnetic field pattern of radiation measured in a plane perpendicular (i.e., transverse) to the propagation direction of the beam.
The wave equation is an important second-order linear partial differential equation for the description of waves—as they occur in classical physics—such as mechanical waves (e.g. water waves, sound waves and seismic waves) or light waves.
Wave propagation is any of the ways in which waves travel.
Whale sounds are used by whales for different kinds of communication.
Wilmer Lanier Barrow (July 26, 1903 – August 29, 1975) was an American electrical engineer, inventor, teacher, industrial manager, and a counselor to government agencies.
A wind instrument is a musical instrument that contains some type of resonator (usually a tube), in which a column of air is set into vibration by the player blowing into (or over) a mouthpiece set at or near the end of the resonator.
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.