Talk:Modulation

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Please be consistent about "Analogue" vs "Analog". As wikipedia redirects all "Analogue" articles to "analog" I changed the spelling here to be consistent. - Xeo 14:43, 12 October 2005 (UTC)

Contents 1 Diagrams 2 mast hai bidu 3 Error(s)? 4 what are the modulation techniques used in mobile networks ???? 5 Too much jargon 6 Polarization Modulation 7 Why?

[edit] Diagrams

Would one or more simple diagrams of some of these concepts help? I am able to make some new (high quality) graphics, or 'refactor' existing ones. Any ideas or requests? At the very least, I think a few graphs illustrating the carrier and signal like the one over at Amplitude modulation ? --Aidan 10:52, 20 February 2006 (UTC)

I don't think we need to replicate the content of other articles here, no. That's why we have the other articles! We could use a system diagram or something generic and high-level like that. One that doesn't deal with a particular modulation scheme but has, you know "data source"->"modulator" -> etc (with a little bit more detail, perhaps). But then that might live better in a general communications article. -Splash^talk 19:18, 12 February 2006 (UTC)

Mmm, I totally agree about replicating graphics. The main reason I suggest this is I think 'Modulation' is a relatively broad/high-level topic. Including image(s) in this article could help demonstrate this idea. Also, from a usability perspective, it can instantly make it clear that this article is definately not about musical modulation (some people don't read). But yeah, now that I think about it, just because an article's 'child' articles have images, doesn't mean it should. (Also, useless images are just that...) Thoughts? --Aidan 10:52, 20 February 2006 (UTC)

[edit] mast hai bidu

consistent ke ma ki aashish

[edit] Error(s)?

Kindly justify the points u think are errors. That touched my heart. --Electron Kid 16:27, 18 December 2005 (UTC)

Several things

1. There was no reason to drop the whole section on "why modulation", since it contains perfectly correct, standard reasons for modulation.
2. The section it was replaced with focuses entirely on antenna length; well yes, modulation has an effect on that by allowing us to shift up in frequency, but it's not the principal reason. It should be mentioned, but an approximate calculation of antenna length doesn't really have a lot to do with modulation: that info belongs elsewhere, and the text already mentioned "smaller...antennas". Plus, the example was a bit peculiar: why would we ever try to transmit at 20kHz?
3. I didn't understand "Logical Reason" at all. We don't transmit signals at that frequency, but I'm not sure with what they would get superimposed, apart from human speech. It's an odd point to make, and again not directly related to the topic of modulation. (And why is this 'reason' logical?)
4. "Redundancy" has nothing to do with modulation. Modulation doesn't introduce or require redundancy. I think you must be thinking of coding, where redundancy is key. Then the text in that section seemed to have nothing to do with redundancy, but did seem to be an unusual statement of the means of modulation — which is already present in clearer, cleaner language right at the top of the article.
5. The musical use of modulation belongs at the top of the article, because that's how we do things like that in lots of other pages.
6. Modulation seems odd in Category:Electronics and Category:Encodings, since the article doesn't talk, or need to talk about electronics (it would belong in the individual schemes' articles) and modulation isn't an encoding.
7. The other categories you added were sensible but we usually only put articles in their most specific subcategories, otherwise the categorization scheme overlaps a lot. So I will put it in Category:Radio modulation modes and Category:Communication theory. overlapping nature of those category names does reveal the mess that the various parts of the comms categorisation scheme is in. -Splash^talk 05:45, 19 December 2005 (UTC)
8. As u stated in ur point no. 1, all the reasons are perfectly sound. It must be explained why modulation theory was developed. This also removes the disambiguation. --Electron Kid 18:22, 23 December 2005 (UTC)
9. I am new, and I took out this part: "There are several reasons to modulate a signal before transmission in a medium. These include the ability of different users sharing a medium (multiple access), and making the signal properties physically compatible with the propagation medium." It didn't make sense. That is because without modulation, it would be impossible to use a signal to carry information. So modulation to allow multiple users to share the medium, or to match the physical properties of the medium, only apply to specific modulation techniques designed to do so, and do not relate to the general property that is modulation.
10. Again, I took out the following part for the same reason as number 9: "Modulation is generally performed to overcome signal transmission issues such as to allow Easy (low loss, low dispersion) propagation as electromagnetic waves Multiplexing — the transmission of multiple data signals in one frequency band, on different carrier frequencies. Smaller, more directional antennas Carrier signals are usually high frequency electromagnetic waves."
11. This is regarding #9 and #10. I understand these changes have been made before, and been undone. I suggest review by a professional before putting the lines back in. I am the second person who thinks it didn't make sense for them to be there.

[edit] what are the modulation techniques used in mobile networks ????

In mobile communication systems, usually a combination of modulation techniques are used. The most common being NB-FM (for GSM), TDMA (now obsolete), FDMA, CDMA, etc.. Elaborate ur quesy/suggestion in the body with only the main theme in the title region. --Electron Kid 04:03, 22 January 2006 (UTC)

I have no idea what you are asking, sorry. -Splash^talk 04:23, 22 January 2006 (UTC)

GSM uses GMSK, I've no idea what "NB-FM" is. TDMA, FDMA and CDMA are multiple access schemes, not modulation schemes. TDMA is not obsolete - it's used in GSM, for instance (GSM also uses FDMA). Oli Filth 11:33, 23 August 2006 (UTC)

[edit] Too much jargon

A quick look around this bundle of articles is not very enlightening for an outsider. It's all incredibly difficult to penetrate. Is there a suitable entry point? Omphaloscope talk 18:42, 1 September 2006 (UTC)

I have added some metaphores from music and numerical examples, in an attempt to give the article a popular scientific touch. But we need lots of illustrations! Mange01 01:45, 27 November 2006 (UTC)

[edit] Polarization Modulation

Somebody can explain modulation formats in a wireless/wireline agnostic way. --பராசக்தி 21:35, 23 November 2006 (UTC)

[edit] Why?

The article doesn't explain why waves would be modulated. It doesn't explain why you would want to have a modulated wave, why an information wave is not suitable for long-range transmissions, etc. Titoxd^{(?!? - cool stuff)} 07:36, 6 April 2007 (UTC)