What is Waveguide: Definition and 102 Discussions

A waveguide is a structure that guides waves, such as electromagnetic waves or sound, with minimal loss of energy by restricting the transmission of energy to one direction. Without the physical constraint of a waveguide, wave intensities decrease according to the inverse square law as they expand into three dimensional space.
There are different types of waveguides for different types of waves. The original and most common meaning is a hollow conductive metal pipe used to carry high frequency radio waves, particularly microwaves. Dielectric waveguides are used at higher radio frequencies, and transparent dielectric waveguides and optical fibers serve as waveguides for light. In acoustics, air ducts and horns are used as waveguides for sound in musical instruments and loudspeakers, and specially-shaped metal rods conduct ultrasonic waves in ultrasonic machining.
The geometry of a waveguide reflects its function; in addition to more common types that channel the wave in one dimension, there are two-dimensional slab waveguides which confine waves to two dimensions. The frequency of the transmitted wave also dictates the size of a waveguide: each waveguide has a cutoff wavelength determined by its size and will not conduct waves of greater wavelength; an optical fiber that guides light will not transmit microwaves which have a much larger wavelength. Some naturally occurring structures can also act as waveguides. The SOFAR channel layer in the ocean can guide the sound of whale song across enormous distances.
Any shape of crossection of waveguide can support EM waves. Irregular shapes are difficult to analyse. Commonly used waveguides are rectangular and circular in shape.

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  1. J

    Optical waveguide modes with different speed, what happens?

    Hi, I'm new on the forum and I would like to start with a question. I've searched for a reply in old posts with no success. If you can help me to find an answer I'll be very glad. Talking about optical modes inside a waveguide. If a waveguide support two different modes, say TM and TE mode...
  2. P

    Rectangular Waveguide centered at the origin

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  3. R

    Induction with waveguide walls

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  4. J

    Waveguide standing wave pattern

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  5. B

    EM Waveguide Modes: What are they and how are they used

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  6. Roodles01

    Understanding Waveguides: Basics and Operation of TE Modes

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  7. J

    Bloch modes and normal waveguide modes- help to clear up

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  8. M

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  9. H

    Size of a waveguide for a given wavelength

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  10. F

    Can the TE01 mode be used in an air-filled rectangular waveguide at 10 GHz?

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  11. E

    Parallel plate waveguide, step discontinuity

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  12. E

    Waveguide discontinuity with centered circular aperture

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  13. A

    Boundary Conditions in a Waveguide

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  14. B

    Experimentally observe waveguide mode pattern

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  15. J

    E and M waveguide theory spec. co-axial

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  16. N

    Mode analysis of rib waveguide

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  17. H

    Force felt by plates in a waveguide

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  18. R

    Exploring Waveguide Cut-Off Frequency Basics

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  19. M

    Rectangular waveguide cavity - Maximum E field

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  20. F

    Reflection in a hollow metal waveguide

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  21. T

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  22. A

    Waveguide - attenuation of power

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  23. A

    Components of E for a waveguide problem.

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  24. G

    Propagation through Subwavelength Waveguide

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  25. D

    Waveguide Dispersion: Investigating Properties & Complications

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  26. G

    Asymmetric Planar Waveguide

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  27. P

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  28. C

    Difference between Material dispersion and waveguide dispersion?

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  29. C

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  30. L

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  31. H

    Fundamental Resonant Frequency of a Waveguide

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  32. L

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  33. Q

    Waveguide consists of two mirrors separated by distance d

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  34. D

    How to Solve TE Waveguide with Different Materials?

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  35. A

    Plasma Waveguide: Frequency Limitations Explained

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  36. B

    COMSOL band structure of photonic crystal waveguide

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  37. G

    Rectangular Waveguide Field in Polar Coordinates

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  38. G

    Finding the Dominant Mode in a Rectangular Waveguide

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  39. R

    Finding Ratio of Lowest Cutoff Frequencies for Waveguide - Quick Question

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  40. R

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  41. K

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  42. M

    Waveguide loss measurement- endfire coupling

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  43. B

    Model QM Behavior of Particle as Probability Waveguide

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  44. B

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  45. B

    How Does a Dielectric Slab Affect Mode Coupling in a 1-D Optical Waveguide?

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  46. S

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  47. C

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  48. L

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  49. N

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  50. D

    Waveguide modes relative power

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