What is the waveguide, are all antennas waveguides?

[sumit007]

What is waveguide

What is waveguidge ?

Is this true -- all antennas are waveguides but not vice versa ?

 

[xischaune]

What is waveguide

yes it is true...
as the name indicates...a waveguide guides the wave...
it is a hollow tube (metallic) that guides the electromagnetic waves from say generator to amplifier etc.
All antennas capture EM waves or emit EM waves...and hence all are waveuides...but not all waveguides capture or emit waves

 

[sumit007]

Re: What is waveguide

thanks for clarification.

 

[flatulent]

Re: What is waveguide

One piece of history. The mathematical analysis of waveguides was done prior to 1900. Electronics is very old technology.

 

[brahma]

Re: What is waveguide

antenna can be stated as a waveguide, it guides the wave in a particular direction, i hope u r aware of horn antennas, which is nothing but a waveguied which is opened in a funnel like fashion and it acts as a antenna. But antenna can also be stated as a transducer, converts electrical signal into EM waves in many cases. But it cannot be called as waveguide all the time, may create confusion.. so be sure abt that...

 

[mmike]

Re: What is waveguide

A waveguide is a structure which guides waves, such as electromagnetic waves, light, or sound waves. There are different types of waveguide for each type of wave.
Contents
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* 1 Electromagnetic waveguides
* 2 Optical waveguides
* 3 Acoustic waveguides
* 4 Sound synthesis

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Electromagnetic waveguides

Main articles: Waveguide (electromagnetism) and transmission line

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. Depending on the frequency, they can be constructed from either conductive or dielectric materials. Waveguides are used for transferring both power and communication signals.
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Optical waveguides

Main article: Waveguide (optics)

Waveguides used at optical frequencies are dielectric waveguides, structures in which a dielectric material with high permittivity, and thus high index of refraction, is surrounded by a material with lower permittivity. The structure guides optical waves by total internal reflection. The most common optical waveguide is optical fiber.
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Acoustic waveguides

Main article: Waveguide (acoustics)

An acoustic waveguide is a physical structure for guiding sound waves. A duct for sound propagation also behaves like a transmission line. The duct contains some medium, such as air, that supports sound propagation.
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Sound synthesis

Main article: Digital waveguide synthesis

Using digital delay lines coupled with digital filters.

 

[suvendu]

What is waveguide

all waveguides are not antennas,waveguide only guides the wave inside a material medium in metal waveguide whereas it guides the wave in dielectric medium in optical waveguide.but antennas guided the wave in free space.

 

[Ahmed Ragab]

Re: What is waveguide

all waveguides are not antennas,waveguide only guides the wave inside a material medium in metal waveguide whereas it guides the wave in dielectric medium in optical waveguide.but antennas guided the wave in free space.

There's one more thing to notice:
Concerning waveguides, in most cases they can not carry TEM waves, only TE or TM waves can propagate through a wave guide. While waves propagate in air as TEM waves. To change from TE or TM into TEM an antenna is placed at the end of the waveguide in order to match the waves coming from the waveguide to the medium it is propagating into.
This shows that waveguides are not antenna's, but they only carry waves from place to place with the least power loss. But an antenna is used to capture waves from the free space, or send them into it.