Surface wave - Citizendia

1 Mechanical waves
2 Electromagnetic waves
- 2.1 Radio propagation
- 2.2 Microwave field theory
3 See also
4 External articles, further readings, and references

In physics, surface wave can refer to a mechanical wave that propagates along the interface between differing media, usually two fluids with different densities. Physics (Greek Physis - φύσις in everyday terms is the Science of Matter and its motion. Please see the article Wave for more information A mechanical wave requires a medium. A surface wave can also be an electromagnetic wave guided by a refractive index gradient. Electromagnetic radiation takes the form of self-propagating Waves in a Vacuum or in Matter. 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 In Vector calculus, the gradient of a Scalar field is a Vector field which points in the direction of the greatest rate of increase of the scalar In radio transmission, a ground wave is a surface wave that propagates close to the surface of the Earth. Radio is the transmission of signals by Modulation of electromagnetic waves with frequencies below those of visible Light. In Telecommunications transmission is the process of sending propagating and receiving an analogue or digital information signal over a physical point-to-point or EARTH was a short-lived Japanese vocal trio which released 6 singles and 1 album between 2000 and 2001

Mechanical waves

In seismology, several types of surface waves are encountered. Seismology (from Greek grc σεισμός seismos, "earthquake" and grc -λογία -logia) is the scientific study of Earthquakes Surface waves, in this mechanical sense, are commonly known as either Love waves (L waves) or Rayleigh waves. A seismic wave is a wave that travels through the Earth, often as the result of an earthquake or explosion. Seismic waves are Waves that travel through the Earth, most often as the result of a tectonic Earthquake, sometimes from an Explosion Love waves have transverse motion (movement is perpendicular to the direction of travel, like light waves), whereas Rayleigh waves have both longitudinal (movement parallel to the direction period of waves that are most damaging is usually 10 seconds or longer. In Elastodynamics, Love waves are essentially horizontally polarized shear waves (SH waves guided by an elastic layer which is "welded" to an elastic half space on Rayleigh waves, also known as the Rayleigh-Lamb Wave or "ground roll" are a type of Surface wave. Surface waves can travel around the globe many times from the largest earthquakes.

Surface wave can describe waves over an ocean, even when they are approximated by Airy functions and are more properly called creeping waves. In Mathematics, the Airy function Ai( x) is a Special function named after the British astronomer George Biddell Airy. According to the principle of Diffraction, when a wave front passes an obstruction it spreads out into the shadowed space Examples are the waves at the surface of water and air (ocean surface waves), or ripples in the sand at the interface with water or air. A wave is a disturbance that propagates through Space and Time, usually with transference of Energy. Water is a common Chemical substance that is essential for the survival of all known forms of Life. Temperature and layers The temperature of the Earth's atmosphere varies with altitude the mathematical relationship between temperature and altitude varies among five Ocean surface waves are Surface waves that occur on the Free surface of the Ocean. Sand is a naturally occurring Granular material composed of finely divided rock and Mineral particles Another example is internal waves, which can be transmitted along the interface of two water masses of different densities. Internal waves are Gravity waves that oscillate within rather than on the surface of a fluid medium

Electromagnetic waves

Ground waves refer to the propagation of radio waves close to or at the surface of the Earth. 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 These surface waves are also known as Norton surface waves, Zenneck waves, Sommerfeld waves, or gliding waves.

Radio propagation

Lower frequencies, especially AM broadcasts in the mediumwave (sometimes called "medium frequency") and longwave bands (and other types of radio frequencies below that), travel efficiently as a surface wave. Frequency is a measure of the number of occurrences of a repeating event per unit Time. Amplitude modulation ( AM) is a technique used in electronic communication most commonly for transmitting information via a Radio Carrier wave For the band see Broadcast (band Broadcasting is the distribution of audio and/or Video signals which transmit Medium Wave (MW is a part of the Medium frequency (MF radio band used mainly for AM broadcasting. The longwave Radio band is a range of frequencies used for AM broadcasting, which extends from 148 A band is a small section of the spectrum of Radio communication frequencies, in which channels are usually used or set aside for the same This is because they are more efficiently diffracted by the figure of the Earth due to their low frequencies. Diffraction is normally taken to refer to various phenomena which occur when a wave encounters an obstacle Ionospheric reflection is taken into consideration as well. The ionosphere reflects frequencies in a certain band, which often changes due to solar conditions. The ionosphere is the uppermost part of the atmosphere, distinguished because it is Ionized by solar radiation The Earth has one refractive index and the atmosphere has another, thus constituting an interface that supports the surface wave transmission. An interface is a surface forming a common boundary among two different phases, such as an insoluble Solid and a Liquid, two immiscible liquids or a liquid

A longitudinal mode of a resonant cavity is a particular standing wave pattern formed by waves confined in the cavity. A longitudinal mode of a Resonant cavity is a particular Standing wave pattern formed by Waves confined in the cavity A resonator is a device or system that exhibits Resonance or resonant behavior that is it naturally oscillates at some frequencies, called its resonance A standing wave, also known as a stationary wave, is a Wave that remains in a constant position The longitudinal waves corresponding to the wavelengths permitted by the cavity are reinforced by constructive interference after many reflections from the cavity's reflecting surfaces. In Physics wavelength is the distance between repeating units of a propagating Wave of a given Frequency. In physics interference is the addition ( superposition) of two or more Waves that result in a new wave pattern

Conductivity of the surface affects the propagation of ground waves, with more conductive surfaces such as water providing better propagation. ^[1] Increasing the conductivity in a surface results in less dissipation. ^[2] The refractive indices are subject to spatial and temporal changes. Since the ground is not a perfect electrical conductor, ground waves are attenuated as they follow the earth’s surface.

Most long-distance LF "longwave" radio communication (between 30 kHz and 300 kHz) is a result of groundwave propagation. Low Frequency or LF refers to Radio Frequencies (RF in the range of 30 kHz&ndash300 kHz The longwave Radio band is a range of frequencies used for AM broadcasting, which extends from 148 Mediumwave radio transmissions (frequencies between 300 kHz and 3000 kHz) have the property of following the curvature of the earth (the groundwave) in the majority of occurrences. Medium Wave (MW is a part of the Medium frequency (MF radio band used mainly for AM broadcasting. At low frequencies, ground losses are low and become lower at lower frequencies. The VLF and LF frequencies are mostly used for military communications, especially with ships and submarines. Very low frequency or VLF refers to radio frequencies (RF in the range of 3 KHz to 30 KHz. Low Frequency or LF refers to Radio Frequencies (RF in the range of 30 kHz&ndash300 kHz

Surface waves have been used in over-the-horizon radar. Over-the-horizon radar, or OTH (sometimes also beyond the horizon, or BTH) is a design concept for Radar systems to allow them to detect targets In the development of radio, surface waves were used extensively. This article covers the main arguments about who had what part in the early development of radio Early commercial and professional radio services relied exclusively on long wave, low frequencies and ground-wave propagation. The longwave Radio band is a range of frequencies used for AM broadcasting, which extends from 148 To prevent interference with these services, amateur and experimental transmitters were restricted to the higher (HF) frequencies, felt to be useless since their ground-wave range was limited. Upon discovery of the other propagation modes possible at medium wave and short wave frequencies, the advantages of HF for commercial and military purposes became apparent. Medium Wave (MW is a part of the Medium frequency (MF radio band used mainly for AM broadcasting. Shortwave Radio operates between the frequencies of 3000 KHz (3 Amateur experimentation was then confined only to authorized frequencies in the range.

Mediumwave, and shortwave reflect off the ionosphere at night, which is known as skywave. Shortwave Radio operates between the frequencies of 3000 KHz (3 Skywave is the propagation of electromagnetic waves bent (refracted back to the Earth's surface by the Ionosphere. Because the solar wind "blows" the ionosphere toward the Earth on the day side, and away from it on the night side, this natural radio "mirror" is much closer to the surface during the day. The solar wind is a Stream of charged particles&mdasha plasma &mdashthat are ejected from the upper atmosphere of the Sun. This prevents the high frequency's propagation from being very effective in daylight hours. At night, mediumwave and shortwave transmissions travel better by skywave. Ground waves do not include ionospheric and tropospheric waves. The ionosphere is the uppermost part of the atmosphere, distinguished because it is Ionized by solar radiation The troposphere is the lowest portion of Earth's atmosphere. It contains approximately 75% of the atmosphere's mass and almost all of its Water vapor and

Microwave field theory

Within microwave field theory, the refractive index of many cavities constitute an interface that supports "surface wave transmission". Surface waves have been studied as part of transmission lines and some may be considered as single-wire transmission line. A transmission line is the material medium or structure that forms all or part of a path from one place to another for directing the transmission of energy A single-wire transmission line (or single wire method) is a method of supplying electrical power through a single-wired electrical conductor

Characteristics and utilizations of the electrical surface wave phenomena include:

The field components of the wave diminish with distance from the interface. In Physics, a field is a Physical quantity associated to each point of Spacetime.
Optical energy is not converted from the surface wave field to another form of energy and the wave does not have a component directed normal to the interface surface.
In optical fiber transmission, evanescent waves are surface waves. An optical fiber (or fibre) is a Glass or Plastic fiber that carries Light along its length In Telecommunications transmission is the process of sending propagating and receiving an analogue or digital information signal over a physical point-to-point or An evanescent wave is a nearfield standing Wave exhibiting Exponential decay with distance

External articles, further readings, and references

Citations

^ "Naval Electrical Engineering Training Series", Chapter 2 Radio Wave Propagation, Ground Waves. Integrated publishing.
^ Antennas and Radio Propagation, TM 11-666, Dept. of the Army, Feb. 1953, pp. 17-23.

Web sites

Eric W. Weisstein, et al. , "Surface Wave", Eric Weisstein's World of Physics, 2006.
"Surface waves". Integrated Publishing (tpub. com).
Brett Ketter, "Surface Wave Theory". University of Wisconsin - Milwaukee.
David Reiss, "Electromagnetic surface waves". The Net Advance of Physics: Special Reports, No. 1
Gary L. Peterson, "Rediscovering the Zenneck wave". Feed Line No. 4. (ed. reproduction available online at Twenty First Century Books)
3D Waves by Jesse Nochella based on a program by Stephen Wolfram, The Wolfram Demonstrations Project. Stephen Wolfram (born August 29, 1959 in London) is a British Physicist, Mathematician and Businessman known for his

Patents

U.S. Patent 2,685,068 , "Surface wave transmission line". George J. E. Goubau
U.S. Patent 2,921,277 , "Launching and receiving of surface waves". George J. E. Goubau.

Standards and doctrines

"Surface wave". Telecom Glossary 2000, ATIS Committee T1A1, Performance and Signal Processing, T1. 523-2001.
"Surface wave", Federal Standard 1037C. Federal Standard 1037C, entitled Telecommunications Glossary of Telecommunication Terms is a United States Federal Standard issued by the General Services Administration
"Surface wave", MIL-STD-188
"Multi-service tactics, techniques, and procedures for the High-Frequency Automatic Link Establishment (HF-ALE): FM 6-02. MIL-STD-188 is a series of US military standards relating to Telecommunications Purpose Faced with “past technical deficiencies in telecommunications 74; MCRP 3-40. 3E; NTTP 6-02. 6; AFTTP(I) 3-2. 48; COMDTINST M2000. 7" Sept. , 2003.

Books

Collin, R. E. , "Field Theory of Guided Waves". New York: Wiley-IEEE Press, 1990.
Waldron, Richard Arthur, "Theory of guided electromagnetic waves". London, New York, Van Nostrand Reinhold, 1970. ISBN 0-442-09167-2 LCCN 69019848 //r86
Weiner, Melvin M. , "Monopole antennas" New York, Marcel Dekker, 2003. ISBN 0-8247-0496-7
Wait, J. R. , "The Waves in Stratified Media". New York: Pergamon, 1962.
Wait, J. R. , "Electromagnetic Wave Theory", New York, Harper and Row, 1985.
Budden, K. G. , " The propagation of radio waves : the theory of radio waves of low power in the ionosphere and magnetosphere". Cambridge (Cambridgeshire); New York : Cambridge University Press, 1985. ISBN 0-521-25461-2 LCCN 84028498
Budden, K. G. , "Radio waves in the ionosphere; the mathematical theory of the reflection of radio waves from stratified ionised layers". Cambridge, Eng. , University Press, 1961. LCCN 61016040 /L/r85
Budden, K. G. , "The wave-guide mode theory of wave propagation". London, Logos Press; Englewood Cliffs, N. J. , Prentice-Hall, c1961. LCCN 62002870 /L

Journals and papers

Zenneck, Sommerfeld, and Norton

J. Zenneck, (translators: P. Blanchin, G. Guérard, É. Picot), "Précis de télégraphie sans fil : complément de l'ouvrage : Les oscillations électromagnétiques et la télégraphie sans fil", Paris : Gauthier-Villars, 1911. viii, 385 p. : ill. ; 26 cm. (Tr. Precisions of wireless telegraphy: complement of the work: Electromagnetic oscillations and wireless telegraphy)
J. Zenneck, "Uber die Fortpflanzung ebener elektromagnetischer Wellen Mngs einer ebenen Leiterflache und ihre Beziehung zur drahtlosen Telegraphie", Ann. der Phwk, vol. 23, pp. 846-866, Sept. 1907. (Tr. "Over the reproduction of even electromagnetic waves of an even leader-flat and their relationship with the wireless telegraphy" )
J. Zenneck, "Eektromagnetische Schwingungen und drahtlose Telegraphie", gart, F. Enke, 1905. xxvii, 1019 p. : ill. ; 24 cm. (Tr. "Electromagnetic oscillations and wireless telegraphy. ")
J. Zenneck, (translator: A. E. Seelig) "Wireless telegraphy,", New York [etc. ] McGraw-Hill Book Company, inc. , 1st ed. 1915. xx, 443 p. illus. , diagrs. 24 cm. LCCN 15024534 (ed. "Bibliography and notes on theory" p. 408-428. )
A. Sommerfeld, "Fortpffanzung elektrodynamischer Wellen an einem zylindnschen Leiter", Ann. der Physik und Chemle, vol. 67, pp. 233–290, Dec 1899. (Tr. Reproduction of electro-dynamic waves at a cylinder leader)
A. Sommerfeld, "Uber die Ausbreitlung der Wellen in der drahtlosen Telegraphie", Annalen der Physik, Vol. 28, March, 1909, pp. 665-736. (Tr. Over the Propagation of the waves in the wireless telegraphy)
A. Sommerfeld, "Propagation of waves in wireless telegraphy", Ann. Phys. , vol. 81, pp. 1367–1153, 1926.
K. A. Norton, "The propagation of radio waves over the surface of the earth and in the upper atmosphere", Proc. IRE, vol. 24, pp. 1367–1387, 1936.
K. A. Norton, "The calculations of ground wave field intensity over a finitely conducting spherical earth", Proc. IRE, vol. 29, pp. 623–639, 1941.

Wait

Wait, J. R. , "Lateral Waves and the Pioneering Research of the Late Kenneth A Norton".
Wait, J. R. , and D. A. Hill, "Excitation of the HF surface wave by vertical and horizontal apertures". Radio Science, 14, 1979, pp 767-780.
Wait, J. R. , and D. A. Hill, "Excitation of the Zenneck surface by a vertical aperture", Radio Science, 13, 1978, pp. 967-977.
Wait, J. R. , "A note on surface waves and ground waves", IEEE Transactions on Antennas and Propagation, Nov 1965. Vol. 13, Issue 6, pg 996- 997 ISSN 0096-1973
Wait, J. R. , "The ancient and modern history of EM ground-wave propagation". IEEE Antennas Propagat. Mag. , vol. 40, pp. 7–24, Oct. 1998.
Wait, J. R. , "Appendix C: On the theory of ground wave propagation over a slightly roughned curved earth", Electromagnetic Probing in Geophysics. Boulder, CO. , Golem, 1971, pp. 37–381.
Wait, J. R. , "Electromagnetic surface waves", Advances in Radio Research, 1, New York, Academic Press, 1964, pp. 157-219.

Others

R. E. Collin, "Hertzian Dipole Radiating Over a Lossy Earth or Sea: Some Early and Late 20th-Century Controversies", Antennas and Propagation Magazine, 46, 2004, pp. 64-79.
F. J. Zucker, "Surface wave antennas and surface wave excited arrays", Antenna Engineering Handbook, 2nd ed. , R. C. Johnson and H. Jasik, Eds. New York: McGraw-Hill, 1984.
Hill, D. and J. R Wait, "Excitation of the Zenneck Surface Wave by a Vertical Aperture", Radio Science, Vol. 13, No. 6, November-December, 1978, pp. 969-977.
Yu. V. Kistovich, "Possibility of Observing Zenneck Surface Waves in Radiation from a Source with a Small Vertical Aperture", Soviet Physics Technical Physics, Vol. 34, No. 4, April, 1989, pp. 391-394.
V. I. Baĭbakov, V. N. Datsko, Yu. V. Kistovich, "Experimental discovery of Zenneck's surface electromagnetic waves", Sov Phys Uspekhi, 1989, 32 (4), 378-379.
Corum, K. L. and J. F. Corum, "The Zenneck Surface Wave", Nikola Tesla, Lightning Observations, and Stationary Waves, Appendix II. 1994.
M. J. King and J. C. Wiltse, "Surface-Wave Propagation on Coated or Uncoated Metal Wires at Millimeter Wavelengths". J. Appl. Phys. , vol. 21, pp. 1119-1128; November,
Georg Goubau, "Surface waves and their application to transmission lines", J. Appl. Phys. , vol. 21, pp. 1119-1128; November,1950.
M. J. King and J. C. Wiltse, "Surfare-Wave Propagation on a Dielectric Rod of Elliutic Cross-Section. " Electronic Communications, Inc. , Tirnonium: kld. . Sci. Rept. 'No. 1, AFCKL Contract No. AF 19(601)-5475; August, 1960.
T. Kahan and G. Eckart, "On the Electromagnetic Surface Wave of Sommerfeld", Phys. Rev. 76, 406–410 (1949).

Other media

L. A. Ostrovsky (ed. ), "Laboratory modeling and theoretical studies of surface wave modulation by a moving sphere", Environmental Technology Laboratory, U. S. Dept. of Commerce, National Oceanic and Atmospheric Administration, Oceanic and Atmospheric Research Laboratories, 2002. OCLC 50325097

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