This page is about waveguides for electromagnetic wave propagation at microwave and radio wave frequencies. For optical waveguides, see Waveguide (optics). For other types of waveguide, see Waveguide. In electromagnetics and communications engineering, the term waveguide may refer to any linear structure that guides electromagnetic waves. However, the original and most common meaning is a hollow metal pipe used for this purpose. Image File history File links Solenoid. ...
Electromagnetism is the physics of the electromagnetic field: a field which exerts a force on particles that possess the property of electric charge, and is in turn affected by the presence and motion of those particles. ...
Electricity (from New Latin Ä“lectricus, amberlike) is a general term for a variety of phenomena resulting from the presence and flow of electric charge. ...
For other senses of this word, see magnetism (disambiguation). ...
Electrostatics (also known as static electricity) is the branch of physics that deals with the phenomena arising from what seem to be stationary electric charges. ...
This box: Electric charge is a fundamental conserved property of some subatomic particles, which determines their electromagnetic interaction. ...
This box: Coulombs torsion balance Coulombs law, developed in the 1780s by French physicist Charles Augustin de Coulomb, may be stated in scalar form as follows: The magnitude of the electrostatic force between two point electric charges is directly proportional to the product of the magnitudes of each...
In physics, the space surrounding an electric charge or in the presence of a time-varying magnetic field has a property called an electric field. ...
In physics and mathematical analysis, Gausss law is the electrostatic application of the generalized Gausss theorem giving the equivalence relation between any flux, e. ...
This article does not cite any references or sources. ...
This article is about the electromagnetic phenomenon. ...
Magnetostatics is the study of static magnetic fields. ...
In physics, Ampères Circuital law, discovered by André-Marie Ampère, relates the circulating magnetic field in a closed loop to the electric current passing through the loop. ...
Magnetic field lines shown by iron filings Magnetostatics Electrodynamics Electrical Network Tensors in Relativity This box: In physics, the magnetic field is a field that permeates space and which exerts a magnetic force on moving electric charges and magnetic dipoles. ...
Magnetic flux, represented by the Greek letter Φ (phi), is a measure of quantity of magnetism, taking account of the strength and the extent of a magnetic field. ...
The Biot-Savart law is a physical law with applications in both electromagnetics and fluid dynamics. ...
A bar magnet. ...
Classical electrodynamics (or classical electromagnetism) is a theory of electromagnetism that was developed over the course of the 19th century, most prominently by James Clerk Maxwell. ...
This box: Electric current is the flow (movement) of electric charge. ...
Lorentz force. ...
Electromotive force (emf) is the amount of energy gained per unit charge that passes through a device in the opposite direction to the electric field existing across that device. ...
For magnetic induction, see Magnetic field. ...
Faradays law of induction (more generally, the law of electromagnetic induction) states that the induced emf (electromotive force) in a closed loop equals the negative of the time rate of change of magnetic flux through the loop. ...
Displacement current is a quantity related to changing electric field. ...
For thermodynamic relations, see Maxwell relations. ...
The electromagnetic field is a physical field that is produced by electrically charged objects and which affects the behaviour of charged objects in the vicinity of the field. ...
This box: Electromagnetic (EM) radiation is a self-propagating wave in space with electric and magnetic components. ...
This article does not cite any references or sources. ...
Conduction is the movement of electrically charged particles through a transmission medium (electrical conductor). ...
Electrical resistance is a measure of the degree to which an electrical component opposes the passage of current. ...
Capacitance is a measure of the amount of electric charge stored (or separated) for a given electric potential. ...
An electric current i flowing around a circuit produces a magnetic field and hence a magnetic flux Φ through the circuit. ...
Electrical impedance, or simply impedance, is a measure of opposition to a sinusoidal alternating electric current. ...
A resonator is a device or part that vibrates (or oscillates) with waves. ...
In special relativity, in order to more clearly express the fact that Maxwells equations (in vacuum) take the same form in any inertial coordinate system, the vacuum Maxwells equations are written in terms of four-vectors and tensors in the manifestly covariant form (cgs units): , and where is...
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In physics, the electromagnetic stress-energy tensor is the portion of the stress-energy tensor due to the electromagnetic field. ...
In electromagnetics and communications engineering, a waveguide is defined as any physical structure that guides electromagnetic waves. ...
Look up waveguide in Wiktionary, the free dictionary. ...
Electromagnetism is the physics of the electromagnetic field: a field, encompassing all of space, composed of the electric field and the magnetic field. ...
In telecommunication, communications system engineering is the translation of user requirements for the exchange of information into cost-effective and low-risk technical solutions in terms of equipment and subsystems. ...
A dielectric waveguide employs a solid dielectric rod rather than a hollow pipe. An optical fibre is a dielectric guide designed to work at optical frequencies. Transmission lines such as microstrip, coplanar waveguide, stripline or coax may also be considered to be waveguides. A dielectric is a physical model commonly used to describe how an electric field behaves inside a material. ...
Fiber Optic strands An optical fiber in American English or fibre in British English is a transparent thin fiber for transmitting light. ...
Transmission lines in Lund, Sweden Electric power transmission is one process in the delivery of electricity to consumers. ...
Cross-section of microstrip geometry. ...
Cross-section diagram of stripline geometry. ...
Wikipedia does not yet have an article with this exact name. ...
The electromagnetic waves in (metal-pipe) waveguide may be imagined as travelling down the guide in a zig-zag path, being repeatedly reflected between opposite walls of the guide. For the particular case of rectangular waveguide, it is possible to base an exact analysis on this view. Propagation in dielectric waveguide, may be viewed in the same way, with the waves confined to the dielectric by total internal reflection at its surface. Some structures, such as nonradiative dielectric waveguide [NRD], and the Goubau line, use both metal walls and dielectric surfaces to confine the wave. The larger the angle to the normal, the smaller is the fraction of light transmitted, until the angle when total internal reflection occurs. ...
A Goubau line, Goubou line, or G-line for short, is a single wire transmission line intended for use at UHF and microwave wavelengths [1]. The line itself consists of a single conductor coated with dielectric material. ...
 Short length of rectangular waveguide (WG17 with UBR120 connection-flanges) |
 Section of flexible waveguide | Image File history File links Waveguide17-with-UBR120-flanges. ...
Image File history File links Waveguide17-with-UBR120-flanges. ...
Image File history File links Metadata Size of this preview: 501 × 599 pixelsFull resolution‎ (2,200 × 2,632 pixels, file size: 861 KB, MIME type: image/jpeg) Section of flexible waveguide at RAF Air Defence Museum Pen used to indicate scale File historyClick on a date/time to view the...
Image File history File links Metadata Size of this preview: 501 × 599 pixelsFull resolution‎ (2,200 × 2,632 pixels, file size: 861 KB, MIME type: image/jpeg) Section of flexible waveguide at RAF Air Defence Museum Pen used to indicate scale File historyClick on a date/time to view the...
History The first waveguide was proposed by J. J. Thomson in 1893 and experimentally verified by O. J. Lodge in 1894; the mathematical analysis of the propagating modes within a hollow metal cylinder was first performed by Lord Rayleigh in 1897. (McLachan, 1947.) Sir Joseph John “J.J.†Thomson, OM, FRS (18 December 1856 – 30 August 1940) was a British physicist and Nobel laureate, credited for the discovery of the electron and of isotopes, and the invention of the mass spectrometer. ...
Year 1893 (MDCCCXCIII) was a common year starting on Sunday (link will display the full calendar) of the Gregorian calendar (or a common year starting on Tuesday of the 12-day slower Julian calendar). ...
1894 (MDCCCXCIV) was a common year starting on Monday (see link for calendar). ...
See also Rayleigh fading Rayleigh scattering Rayleigh number Rayleigh waves Rayleigh-Jeans law External links Nobel website bio of Rayleigh About John William Strutt MacTutor biography of Lord Rayleigh Categories: People stubs | 1842 births | 1919 deaths | Nobel Prize in Physics winners | Peers | British physicists | Discoverer of a chemical element ...
1897 (MDCCCXCVII) was a common year starting on Friday (see link for calendar). ...
Principles of operation Depending on the frequency, waveguides can be constructed from either conductive or dielectric materials. Generally, the lower the frequency to be passed the larger the waveguide is. For example the natural waveguide[1] the earth forms given by the dimensions between the conductive Ionosphere and the ground as well as the circumference at the median altitude of the earth is resonant at 7.83 Hz. This is also known as Schumann resonance. Waveguides can also be less than a millimeter in width. An example might be those that are used in extremely high frequency (EHF) Satellite Communications(SATCOM). There is a formula for calculating waveguide dimensions, more information may be found at this website[2]. Conduction is the movement of electrically charged particles through a transmission medium (electrical conductor). ...
A dielectric is a physical model commonly used to describe how an electric field behaves inside a material. ...
The Schumann resonance is a set of spectrum peaks in the extremely low frequency (ELF) portion of the Earths electromagnetic field spectrum. ...
Extremely high frequency is the highest radio frequency band. ...
For other uses, see Satellite (disambiguation). ...
Bold text===Analysis===
Electromagnetic waveguides are analyzed by solving Maxwell's equations, or their reduced form, the electromagnetic wave equation, with boundary conditions determined by the properties of the materials and their interfaces. These equations have multiple solutions, or modes, which are eigenfunctions of the equation system. Each mode is therefore characterized by an eigenvalue, which corresponds to the axial propagation velocity of the wave in the guide. For thermodynamic relations, see Maxwell relations. ...
Lasers used for visual effects during a musical performance. ...
In mathematics, boundary conditions are imposed on the solutions of ordinary differential equations and partial differential equations, to fit the solutions to the actual problem. ...
In mathematics, an eigenfunction of a linear operator A defined on some function space is any non-zero function f in that space that returns from the operator exactly as is, except for a multiplicative scaling factor. ...
In mathematics, a number is called an eigenvalue of a matrix if there exists a nonzero vector such that the matrix times the vector is equal to the same vector multiplied by the eigenvalue. ...
Waveguide propagation modes depend on the operating wavelength and polarization and the shape and size of the guide. The longitudinal mode of a waveguide is a particular standing wave pattern formed by waves confined in the cavity. The transverse modes are classified into different types: For other uses, see Wavelength (disambiguation). ...
In electrodynamics, polarization (also spelled polarisation) is the property of electromagnetic waves, such as light, that describes the direction of their transverse electric field. ...
The first six longitudinal modes of a plane-parallel cavity. ...
Vibration and standing waves in a string, The fundamental and the first 6 overtones A standing wave, also known as a stationary wave, is a wave that remains in a constant position. ...
A transverse mode of a beam of electromagnetic radiation is a particular intensity pattern of radiation measured in a plane perpendicular (i. ...
- TE modes (Transverse Electric) have no electric field in the direction of propagation.
- TM modes (Transverse Magnetic) have no magnetic field in the direction of propagation.
- TEM modes (Transverse ElectroMagnetic) have no electric nor magnetic field in the direction of propagation.
- Hybrid modes are those which have both electric and magnetic field components in the direction of propagation.
In hollow metallic waveguides, the fundamental modes are derived from the transverse electric TE1,0 mode for rectangular and TE1,1 for circular waveguides. Also, in hollow waveguides, TEM waves are not possible, since Maxwell's Equations will give that the electric field must then have zero divergence and zero curl and be equal to zero at boundaries, resulting in a zero field. (or, equivalently,  with boundary conditions guaranteeing only the trivial solution). However, TEM waves can propagate in coaxial cable. The fundamental tone, often referred to simply as the fundamental, is the lowest frequency in a harmonic series. ...
For thermodynamic relations, see Maxwell relations. ...
TE1,0 mode of a rectangular hollow metallic waveguide. waveguide propagation mode transverse electric 1,0 File history Legend: (cur) = this is the current file, (del) = delete this old version, (rev) = revert to this old version. ...
| TE1,1 mode of a circular hollow metallic waveguide. waveguide propagation mode transverse electic 1,1 File history Legend: (cur) = this is the current file, (del) = delete this old version, (rev) = revert to this old version. ...
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Hollow metallic waveguides In the microwave region of the electromagnetic spectrum, a waveguide normally consists of a hollow metallic conductor. Hollow waveguides must be one-half wavelength or more in diameter in order to support one or more transverse wave modes. This article is about the type of Electromagnetic radiation. ...
Legend γ = Gamma rays HX = Hard X-rays SX = Soft X-Rays EUV = Extreme ultraviolet NUV = Near ultraviolet Visible light NIR = Near infrared MIR = Moderate infrared FIR = Far infrared Radio waves EHF = Extremely high frequency (Microwaves) SHF = Super high frequency (Microwaves) UHF = Ultra high frequency VHF = Very high frequency HF = High...
Waveguides are often pressurized to inhibit arcing/multipaction, allowing higher power. Conversely, waveguides may be required to be evacuated as part of evacuated systems. (e.g. electron beam systems) Multipaction is a process in which a charged particle inside a gap in a vacuum environment (or low pressure), oscillates due to the influence of an externally applied oscillating electric field of large strength, and every time it hits the gap walls it causes other charged particles to be released. ...
A slotted waveguide is generally used for radar and other similar applications. The waveguide structure has the capability of confining and supporting the energy of an electromagnetic wave to a specific relatively narrow and controllable path. A slotted waveguide is a waveguide that is used as an antenna in microwave radar applications. ...
For other uses, see Radar (disambiguation). ...
Electromagnetic radiation is a propagating wave in space with electric and magnetic components. ...
A closed waveguide is an electromagnetic waveguide (a) that is tubular, usually with a circular or rectangular cross section, (b) that has electrically conducting walls, (c) that may be hollow or filled with a dielectric material, (d) that can support a large number of discrete propagating modes, though only a few may be practical, (e) in which each discrete mode defines the propagation constant for that mode, (f) in which the field at any point is describable in terms of the supported modes, (g) in which there is no radiation field, and (h) in which discontinuities and bends cause mode conversion but not radiation. A dielectric is a physical model commonly used to describe how an electric field behaves inside a material. ...
For an electromagnetic field mode varying sinusoidally with time at a given frequency, the propagation constant is the logarithmic rate of change, with respect to distance in a given direction, of the complex amplitude of any field component. ...
The magnitude of an electric field surrounding two equally charged (repelling) particles. ...
For other uses, see Radiation (disambiguation). ...
Hollow metallic waveguides are far narrower than the wavelength of operation. They can take the form of single conductors with or without a dielectric coating, e.g. the Goubou line and helical waveguides. A single-wire transmission line (or single wire method) is a method of supplying electrical power through a single wired electrical conductor. ...
VSWR measurements may be taken to ensure that a waveguide is contiguous and has no leaks or sharp bends. If such bends or holes in the waveguide surface are present, this may diminish the performance of both TX and RX equipment strings. Arcing may occur if there is a hole, if transmitting at high power, usually 200 watts or more. Waveguide plumbing[3] is crucial for proper waveguide performance. Reflected power may occur and damage equipment as well. Another cause for a bad VSWR in a waveguide is moisture build up and can typically be prevented with silica gel which is a desiccant. Due to the negative effect of moisture buildup within the waveguide desiccant silica gel canisters may attached with screw-on nibs. Beads of silica gel Silica gel is a granular, porous form of silica made synthetically from sodium silicate. ...
A dessicant is a hygroscopic substance that induces or sustains a state of dryness (desiccation) in its local vicinity in a moderately-well sealed container. ...
Dielectric rods for microwaves Dielectric rod waveguides, in linear arrays of short transverse conductors, and planar resistive conductors use the same principle as optical waveguides.
These function via a refractive index effect where the waveguide slows the EM wave velocity below the free space velocity, continuously bending the relatively wide EM wavefronts towards the narrow waveguide and keeping them entrained. Helical waveguides and linear arrays of short conductors are used as part of "end-fire" antennas such as the helical antenna and Yagi antenna. Planar resistive waveguides are used in Over-The-Horizon radar and the Ground Wave Emergency Network, where the resistive surface of the Earth or ocean serves to slow the waves below free space velocity; entraining them and forcing them to follow the curvature of the Earth. Several waveguides based on entrainment of EM waves also exist. The refractive index (or index of refraction) of a medium is a measure for how much the speed of light (or other waves such as sound waves) is reduced inside the medium. ...
A helical antenna is an antenna consisting of a conducting wire wound in the form of a helix. ...
A Yagi-Uda antenna. ...
Over-The-Horizon radar (OTHR) is a design concept for radar system to overcome the problem that radio waves (a form of light) travel in a straight line, making over the horizon detection difficult. ...
The Ground Wave Emergency Network (GWEN) is an array of radio transceivers distributed across the continental USA, operating in the VLF frequency band, and intended for military communications during a nuclear war. ...
Applications Waveguides can be constructed to carry waves over a wide portion of the electromagnetic spectrum, but are especially useful in the microwave and optical frequency ranges. Waveguides are used for transferring both power and communication signals, usually for short distances. Bell Labs in the 1970s built a waveguide line several miles long, to study possible use for intercity communication, but advances in optical fiber disrupted the plan. Legend γ = Gamma rays HX = Hard X-rays SX = Soft X-Rays EUV = Extreme ultraviolet NUV = Near ultraviolet Visible light NIR = Near infrared MIR = Moderate infrared FIR = Far infrared Radio waves EHF = Extremely high frequency (Microwaves) SHF = Super high frequency (Microwaves) UHF = Ultra high frequency VHF = Very high frequency HF = High...
This article is about the type of Electromagnetic radiation. ...
For the book by Sir Isaac Newton, see Opticks. ...
In physics, power (symbol: P) is the rate at which work is performed or energy is transmitted, or the amount of energy required or expended for a given unit of time. ...
Bell Laboratories (also known as Bell Labs and formerly known as AT&T Bell Laboratories and Bell Telephone Laboratories) was the main research and development arm of the United States Bell System. ...
Optical fibers An optical fiber (or fibre) is a glass or plastic fiber designed to guide light along its length. ...
See also In waveguide design and construction, angular misalignment loss is Power loss caused by the deviation from optimum angular alignment of the axes of source-to-waveguide, waveguide-to-waveguide, or waveguide-to-detector. ...
To meet Wikipedias quality standards, this article or section may require cleanup. ...
A bode plot of the Butterworth filters frequency response, with corner frequency labeled. ...
The relative dielectric constant of a material under given conditions is a measure of the extent to which it concentrates electrostatic lines of flux. ...
This box: Electromagnetic (EM) radiation is a self-propagating wave in space with electric and magnetic components. ...
In satellite dish and antenna design parlance, a feedhorn (or feed horn) is a horn antenna used to convey radio waves between the transceiver (transmitter and/or receiver) and the reflector. ...
In telecommunication, a filled cable is a cable that has a nonhygroscopic material, usually a gel, inside the jacket or sheath. ...
For other types of horns, see horn (disambiguation). ...
Leaky mode: In an optical fiber or other form of waveguide, a mode having a field that decays monotonically for a finite distance in the transverse direction but becomes oscillatory everywhere beyond that finite distance. ...
A klystron is a specialized vacuum tube (evacuated electron tube) called a linear-beam tube. ...
For an optical fiber, Radiation mode, or unbound mode, is an unbound mode. ...
Radio frequency, or RF, refers to that portion of the electromagnetic spectrum in which electromagnetic waves can be generated by alternating current fed to an antenna. ...
Radio propagation is a term used to explain how radio waves behave when they are transmitted, or are propagated from one point on the Earth to another. ...
A transmission medium is any material substance, such as fiber-optic cable, twisted-wire pair, coaxial cable, dielectric-slab waveguide, water, or air, that can be used for the propagation of signals, usually in the form of modulated radio, light, or acoustic waves, from one point to another. ...
A cantenna is a directional waveguide antenna for long-range Wi-Fi used to increase the range of (or snoop on) a wireless network. ...
References This article is based in part on material from Federal Standard 1037C and from MIL-STD-188, and ATIS Federal Standard 1037C, entitled Telecommunications: Glossary of Telecommunication Terms is a United States Federal Standard, issued by the General Services Administration pursuant to the Federal Property and Administrative Services Act of 1949, as amended. ...
MIL-STD-188 is a series of U.S. military standards relating to telecommunications. ...
The Alliance for Telecommunications Industry Solutions (ATIS) is a standardization organization for information technologies (ITs) in the telecommunications industry. ...
- J. J. Thomson, Recent Researches (1893).
- O. J. Lodge, Proc. Roy. Inst. 14, p. 321 (1894).
- Lord Rayleigh, Phil. Mag. 43, p. 125 (1897).
- N. W. McLachlan, Theory and Applications of Mathieu Functions, p. 8 (1947) (reprinted by Dover: New York, 1964).
Further reading - George Clark Southworth, "Principles and applications of wave-guide transmission". New York, Van Nostrand [1950], xi, 689 p. illus. 24 cm. Bell Telephone Laboratories series. LCCN 50009834
Dr. 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 discovery of waveguides in the early 1930s. ...
External links - Patents
- Southworth, U.S. Patent 2,407,690 , "Wave guide electrotherapeutic system"
- Hopper, U.S. Patent 2,806,138 , "Wave guide frequency converter", September 10, 1957
- Websites
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