Talk:Waveguide (electromagnetism)

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SLAC defn: A waveguide is an evacuated rectangular copper pipe. It carries electromagnetic waves from one place to another without significant loss in intensity--Light current 01:54, 31 January 2006 (UTC)

Contents

[edit] Merger

I have suggested merging this article with optical waveguides, as optical waves are higher frequency electromagnetic waves. I think the problem could be solved if optical waveguides was made a subsection of this article. --Fred138 01:44, 11 October 2006 (UTC)

Hi. I was planning to expand the Waveguide (electomagnetism) page considerably. I've only got as far as rewriting the introduction and adding a picture, but I was intending (eventually):

  • Simple analysis of rectangular guide in terms of superposed plane-waves / multiple reflections.
  • Standard analysis of rectangular guide by solving Maxwell's equations by separation of variables.
  • Ditto for circular guide.
  • Mention of double-ridge guide etc.
  • Definition of dominant mode. Uses of over-moded guide.
  • Discussion of relative merits/uses of 2:1 rectangular guide, circular/square guide and two-conductor lines (coax/microstrip).
  • Table of standard rectangular guide WG/WR.
  • Mention of waveguide components (selection from: bends, transitions/tapers, junctions, magic-T, power-dividers, polarizers, filters, branch-couplers etc.) - with some more pictures!
  • Mention of E-plane split construction of rectangular guide components.

This might make a merged page a bit long and a bit one-sided (weighted towards hollow metal guides). Of course there's no real physical distinction between microwave and optical guides, but the technology is a bit different so it's a convenient split. So I have a slight preference for separate pages. --catslash 13:34, 11 October 2006 (UTC)

Although, there is also a page on Fiber Optics and its applications here on wikipedia. Perhaps one could reference that and do away with the optical waveguide article? Then again, if you plan to make this one that in depth, then I guess it would be alright to keep them separate. They just both seem too short at present, which is why I suggested it. Perhaps making the optics one more in depth as well could help.--Fred138 14:28, 11 October 2006 (UTC)

Personally, I have no plans to make the Waveguide (optical) page more in-depth. Also, there is a speaking tube page to cover the acoustic case. So I'm persuaded that merging is a good plan. If, in the distant future, this article becomes too long, then we can think again, and (say) split dielectric guides from hollow metal guides. --catslash 14:48, 11 October 2006 (UTC)

I don't think merging them is a good idea. Hollow metal microwave guides are sufficiently different from dielectric optical waveguides to merit two articles. Whether one makes the break by wavelength or by hollow metal vs. dielectric is a matter for discussion. Note, though, that not all optical waveguides are fibers. Non-fiber optical waveguides are extremely important technologically. They are widely used in photonics and semiconductor lasers.--Srleffler 08:52, 11 November 2006 (UTC)

I think it would be a great idea to merge the Waveguide (optics) with Waveguide (electromagnetism). These topics are identical and similar treatment of these waveguides can be found in both optics and E&M texts. Waveguide (electromagnetism) should also be added to the optics category.Gfutia 22:19, 17 October 2007 (UTC)

[edit] Merger into Waveguides

I think that there should be one big merger into one article called waveguides. Then you start with the general waveguide going into TE, TM, and TEM waveguides, Rectangular waveguides, Coaxial transmission Line, Optical, etc... Just follow the two standard books in Electrodynamics (Giffiths and Jackson). This is the way they treat waveguides.

[edit] Pressurized guide

This is a surprising statement:

"In some waveguides, there may be a positive gas pressure internally present, allowing for the detection of potentially dangerous RF leaks. Another solution to detect RF leakage of a waveguide is to have a partial vacuum present inside. Then leaks can be detected in basically the same way."

I think there may be some confusion here. Waveguides are sometimes pressurized to inhibit arcing/multipaction, and are sometimes evacuated because they are part of evacuated systems (e.g. electron beam systems), but I've never heard of pressurization to detect breaches. Are there any references to support this claim? --catslash 23:20, 8 September 2006 (UTC)

The "pressurize to determine dangerous leaks" is the wrong answer on the beginners radar test. - Bogus, going to change it.71.110.64.173 23:11, 1 July 2007 (UTC)

You could have a horn feed for a cassegrain antenna for example that would require a weather-tight dielectric window across the aperture. You would need to make the whole waveguide system gas tight with rubber gaskets and then put in a slightly positive gas pressure of some suitably dry high breakdown gas and monitor the flow rate. If you get a small leak you can detect the increased flow rate and hopefully it will keep the rain and dust out until you can repair it. ChrisAngove 20:00, 24 November 2006 (UTC)

Bad pressurized WG info replaced. Fubartu 00:25, 2 July 2007 (UTC)

[edit] Waveguide resistive terminations

We bady need some stuff on the dummy loads used with WG. Any offers? --Light current 23:01, 25 January 2007 (UTC)



[edit] Distinguishing between Optical, RF, EM and "Dielectric" vs "Pipe" WGs

Hi all. I'm just here disambiguating "Beam" and this isn't my field but the WG article TITLEs are a little muddled. Might I suggest that:

Reasons:

  • It's all EM
  • EM in fibers is often not visible
  • Optical is also a general term refering to any EM bouncing around, e.g. GO, PO and BWGs (which don't even have a reference in WP!?)

I've drop this in Waveguide, WG(em) and WG(opt) as there doesn't seem to be much overlap between the "talkers". Enjoy, Saintrain 18:03, 12 February 2007 (UTC)

Hollow-metal-pipe versus dielectric, seems a reasonable split to me - see last two paragraphs of #Merger (above).--catslash 21:13, 12 February 2007 (UTC)
Um, why would we want waveguide hollow metal pipe? If anything, there should be 1 article about waveguides that includes the math required to analyze them. If a discussion of different geometries is needed than it should be placed in a section of that article. Gfutia 19:14, 19 October 2007 (UTC)

[edit] Merging

I would recommend not merging the two pages together. Instead you may want to retitle waveguide (electromagnetism) to waveguide (RF) or waveguide (microwave). Optical waveguides are almost exclusively fiber optic based where RF/microwave/millimeter wave waveguides are almost always hollow metallic tubing. Two very different concepts. —The preceding unsigned comment was added by 199.46.200.233 (talk) 23:07, 15 March 2007 (UTC).