Talk:Noise (electronics)

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Classification[edit]

Gaussian noise, white noise, and pink noise are not types of electronic noise. They're just words to describe the characteristics of noise, regardless of the source or the medium the noise exists in (statistics of natural phenomena can be pink without involving electronics at all).

Types of electronic noise would be shot noise, thermal noise, flicker noise, burst noise, and avalanche noise. — Omegatron 14:03, 1 September 2006 (UTC)

Agreed!--Light current 15:01, 1 September 2006 (UTC)
Ok. Let's do it. Also see Talk:Pink noise#SplitOmegatron 16:11, 1 September 2006 (UTC)

Unwanted[edit]

The opening says Electronic noise is an unwanted signal characteristic, but that is not true. There are applications for using (and generating) noise. Otherwise you wouldn't have things like [1] [2] [3]. They're mostly for crypto, but I think I've seen uses in ham-radio (can't dig up the info ATM). Yngvarr (c) 12:06, 14 April 2008 (UTC)

- Noise does refer to unwanted signal characteristics, technically. This is not true in common usage. The examples provided refer to specific spectra whereas "noise" is not a specific spectrum. Some types of noise do have colors used in their name to identify different spectra, however, none of these is also represented by a particular pattern in the time domain. In the frequency domain there is only one graphical representation.

  • Most sources of "random" noise are not random. Rather they reflect a fingerprint of the frequencies inherent to the environment from which the noise is taken. random.org provides a detailed explanation of this and it provides tests that can be used to determine if input is truly random. Atmospheric noise and the non-linear disruptions that can be measured when a clean, constant voltage is applied in reverse across a bipolar junction, are random. Signals that can be used as random sources from inside a pc are not random because they reflect, in part, the synchronous noise produced from crytals and from state changes on the several bus lines.
  • "White" noise is a reference to a broadband signal where are frequencies in the spectrum of interest are represented at an identical intensity. "Pink" noise is similar, but the intensity varies in a complementary way to "normal" human hearing. That is, the intensity of each frequency sounds as though they are at the same intensity.
  • "Useful" noise comes in most colors used to refer to colors in the visible spectrum.
  • Ham receivers can be used to listen to atmospheric noise proabbly has little use in an intelligible Ham signal. Rather, noise comprises the "noise floor" of the signal-to-noise ratio. Some cryptographic methods use noise to generate randomness in a hash table that is later used to create a cipher. The "random" aspect of noise suggests it cannot be reproduced later so decryption couldn'tnot happen. If any random value worked, the cipher would probably not be of much value. UUIDs are an example of a random value in a hash table. The second column would be whatever you wanted to represent as a UUID, such as a social security number.

Kernel.package (talk) 08:05, 9 December 2009 (UTC)

Effects of noise[edit]

I think it will be appropriate that a description of the effects of noise be also included in the article. This could be in the form of noise that produces a noise emf or a noise current. Many students of electrical and electronic circuits would be interested to know what the resulting effect is; how exactly is the real or wanted signal affected by the emf or current fluctuations. Sridhar10chitta (talk) 02:00, 28 August 2008 (UTC) Sridhar Chitta:

Imported talk page from Noise level[edit]

The above is inacacurate to the extreme. Typically noise is measured in terms of the sound pressure above or below a particular reference point. SPL or sound pressure level is computed as: dB=20 X log of pressure measured over .0002dynes per CM squared. It is a logarithmic scale. SPL is the standard for specifying sound level. —Preceding unsigned comment added by 24.197.246.79 (talkcontribs) 23:35, 12 March 2006

  • The last statement is true. But audible noise comprises a very, very smal portion of the entire spectrum that can include noise. As a result, measurement in SPL is unusual in any environment other than audio applicaitons. Standards that require measurement of noise use either dBm or dBv, whcih are measures of electric field density. Since any of this requires that the signal of interest exists at some point, as an electric signal, SPL makes little sense. Meters used for measuring the sound level of noise convert audible range noise into an electrical signal first.

Kernel.package (talk) 08:17, 9 December 2009 (UTC)

Recent Move[edit]

Maybe I'm missing something, but I can't find any discussion of the recent move from 'Electronic Noise' to 'Noise (electronics)', let alone a discussion. For the record, I oppose the move - although I would be interested to see a discussion which could change my mind. GyroMagician (talk) 08:13, 3 September 2009 (UTC)

I support the move. It is in line with how other articles are named here. Mange01 (talk) 21:20, 13 December 2009 (UTC)

Confused Article[edit]

I think this page has recently become rather confused. We currently have a rather rambling introductory paragraph that is almost as long as the body of the article, without much structure or flow.

Also, maybe there was actually a good case to keep the previous "Noise (telecommunications)" page? Some of the information here seems very specific to comms systems - although maybe a bit of re-ordering would fix that.

—Preceding unsigned comment added by GyroMagician (talkcontribs)

Technical details like noise measures may be moved from the article lead to the measure section. Please do that if you have time. But everything in this article is related to communications, and the communication article was really poor, so I don't see the point of having separate articles. Mange01 (talk) 17:29, 26 December 2009 (UTC)
I would argue that noise (electronics) and noise (telecommunications) are subtly different topics. Noise in electronics is specific to physical layer channels, while noise in telecommunications applies to a much broader range of channel models, with statistical error probabilities instead of actual signal noise. This is the reason why I was looking for a proper article on channel noise, and created a redirect to communication channel in the mean time. Nageh (talk) 11:16, 1 March 2010 (UTC)
It's interesting to see different viewpoints. I agree that the two topics are different. I think noise (electronics) should be about the fundamental physical processes, relevant to all electronic measurement. I see noise (telecommunications) as one particular application of that. But then I'm a physicist, so there's my bias. I'm still planning to try to improve this article, but haven't found time yet. I think I know enough to write the electronics part, but I certainly don't know enough to write the telecomms part. Maybe we should try to produce something together? As there was previously a noise (telecommunications) page that wasn't very useful, I think we should initially try to separate the 'electronics' and 'telecommunications' parts as sections within one page, then split it later if they grow large enough to justify it. What do you think? GyroMagician (talk) 11:58, 1 March 2010 (UTC)
It sounds reasonable to first separate the two issues within the article. I would propose the split, but I would wish more knowledgeable people on the subject than me to write on the different topics of noise in electronics and telecommunications. I was thinking of User:Mange01 to add to the discussion and the article content. Cheers, Nageh (talk) 14:31, 1 March 2010 (UTC)
Yeh okay. Mange01 - do you fancy having a go? GyroMagician (talk) 12:17, 2 March 2010 (UTC)
 :) Hope you didn't get me wrong. I'm not a telecommunications engineer though I do have a fair background on multiple issues involved. It's just that I think people more knowledgeable on the subject than me could contribute in a better way than me (and I figured Mange01 had an educational background in telecommunications). Of course anybody is invited! :) Nageh (talk) 15:22, 2 March 2010 (UTC)
Nope, not at all, and I certainly didn't mean to exclude mange01 :-) I think we could improve this article, and it's an important enough topic that it deserves some work. On a related note, I've been trying to improve Signal-to-noise ratio. Would you two mind having a look at it? Thanks GyroMagician (talk) 20:20, 2 March 2010 (UTC)
I'm flattered Nageh. I'm currently a little bit busy. However, GyroMagician really improved this article as well as the signal-to-noise ratio article. I still don't see in what way the merge detoriated the article.
From communication engineering point of view, the article would be improved if it had a section on white gaussian noise (which is not only is caused by thermal noise), a section about phase noise, one about quantification noise, and perhaps one about the difference between noise, interference and distorsion. The formula N=B*N_0 is essential, where the noise density N_0 = kT in case of thermal noise. Some of these things have been removed from the article.Mange01 (talk) 22:07, 2 March 2010 (UTC)

(outdent) These are good ideas - I'm beginning to understand a why telecomms belong in this article (as I said, not my field, so I'm a bit naive!). There is already a page about Additive white Gaussian noise which is in pretty good shape, so we would only need a short section here. Noise spectral density is a bit shorter and probably needs some work, as I think phase noise will. I've been looking at Signal-to-quantization-noise ratio and quantization error already. Again, a short paragraph here linking to those pages (or single page if we merge them) would work nicely.

I think the main thing that has put me off working on these articles is the size of the project! There is clearly a lot to do - but hopefully if we can focus on a page (or two) at a time we could improve things. I think the problem with this page is that it contains lots of information, but it is rather tangled up. Try to see it from the perspective of someone who knows nothing about the subject. Looking at the article again, my problem is only really with the lede, much of which should be split out in sections in the article body. I don't think the merge was the problem here - it is more a case of lots of us making small changes over time, without a larger overview. I'll try and start work on it. Mange01, if you find time to work on the lede or the sections you propose, that would be excellent. And I'm glad you like what I've been trying to do with SNR - I'm stuck with that page now - it doesn't feel finished, but I can't see where to go next. Suggestions are always welcome ;-) GyroMagician (talk) 09:28, 5 March 2010 (UTC)

Exterior sources of noise[edit]

This article describes the types of noise in electronic circuits. But in telecommunication, the interference from exterior sources can also be considered as noise. Thus industrial noise, atmospheric noise and galactic noise etc. which decrease the S/N ratio at the receiver should also be listed as types of noise. Nedim Ardoğa (talk) 13:05, 13 January 2010 (UTC)

I think this is where the page becomes slightly confusing, and where we maybe need a 'noise (telecomms)' page. Although, thinking about it, maybe a section "1.6 External noise" would work, describing interference (50Hz, etc), Atmospheric noise and Cosmic background radiation, but making it clear that these sources are outside the circuit, in contrast to the others. Yeah, okay, I've talked myself around. Do you fancy writing it? GyroMagician (talk) 19:18, 13 January 2010 (UTC)
In telecommunications, noise refers to any effect which perturbs signal quality (both digital and analog) during transmission over a channel. Given the content of this article, this definition of noise regarding telecommunications should be stated clearly in the article noise, and noise (telecommunications) better be redirected to that article. Please note that noise in modern telecommunications is not restricted to electronics, but, besides radio transmission, can even appear in higher layers (e.g., buffer overrun in packet routers resulting in erasures). Nageh (talk) 16:25, 3 March 2010 (UTC)
Found another article related to signal noise and channel noise: background noise. Nageh (talk) 19:22, 8 April 2010 (UTC)
Exterior sources are often but not always considered as electromagnetic interference rather than noise. The difference between interference and noise is discussed in the article lead. Has someone seen a source clarifying this difference further?
Should the article have a section about noise types (e.g. Gaussian noise, phase noise, etc) or noise characteristics? In that case, exterior sources that couses for example white Gaussian noise could be discussed in that section.
There is very little difference between noise sources in electronics and telecommunications. The only important difference between the two subjects is that in telecommunications, noise is always unwanted.
I don't understand the difference between noise and background noise from that article. I doubt that background noise deserve its own article. It should be merged with other noise articles. Mange01 (talk) 11:12, 10 April 2010 (UTC)
I think we should merge background noise into the main noise page, rather than here. Here we could make some mention of electrical background noise here though (maybe as section 1.6, as I suggested above). A single section about noise types might work well - apart from Gaussian and phase noise, what else would you include?
The more I learn about the meaning of noise in telecommunications, the more I think it needs a separate page. Especially in digital comms, the meaning of noise can be very different to the basic physical processes that produce Johnson or shot noise. To describe both in the same page is confusing. I understand the difference between noise and interference to be that noise is truly random, while interference is a signal with some structure, just not the signal that you're hoping to detect. I think this page should focus on the truly random stuff, which is an interesting physical phenomenon in itself. However, according to the definition given at Interference_(communication), noise would be a subset of interference, which I think also makes sense.
While we're trying to catch all related pages, there is a very mathsy AWGN page, and a brief Gaussian noise. We should probably merge the second into the first (or even delete and make it redirect)? GyroMagician (talk) 12:15, 10 April 2010 (UTC)
As you have noticed, I'm a mergist rather than deletionist, so I support all your merge suggestions... But I should admit, often a lot of text is deleted during a merge.
If I would write a Wikipedia article about noise in communications, I would pretty much copy this rather well-written article. I don't see anything that should be left out. Telecom people just like people in electronics study the concept of noise during a course in signal theory or stochastic processes. Thus, the definitions and measures are essentially the same. Telecom and electronics both belong to electrical engineering, and this article is currently about noise in electrical engineering. You mention dig com. In the article about bit error rate, phase shift keying and some other digital modulation schemes, the relationship between noise and bit error probability is discussed. However, I see no point in discussing that in a noise article. Johnson noise is always an effect of the temperature (which in outer space is affected by the background radiation in universe), in electronics as well as telecoms. There are other sources of white Gaussian noise that briefly could be mentioned somewhere in the article, but that is less important. I don't know what shot noise sources you have in mind.
Regarding the difference between noise and interference: Is your distinction (noise = random, interference = deterministic) true for electronics? Telecom literature is i.m.o. not consequent here. The term Electromagnetic interference (EMI) refers to radiation from all kinds of electrical devices, e.g. motor ignition systems, electrical power distribution, radio transmitters, cross-talk in telecom cables, etc. The EMI might be random as well as deterministic/periodic. We don't call it "electromagnetic noise", even if it is stochastic. Note that cross-talk from other transmitters are often considered as stochastic signals in telecommunications. Interfering signals may also have white spectrum within the channel bandwidth, but the distribution is not Guassian. Another possible distinction occurring in the literature (e.g. in the area of radio resource management) is that interference are from sources that we have control over and can plan or manage - e.g. crosstalk (co-channel interference) or adjacent channel interference from other transmitters within the same system or cable or network. Radiation from exterior transmitters and other electrical devices are in that case considered as noise, or simply ignored. In wireless communication, the noise is dominated by thermal noise. We differ interference limited radio systems (e.g. cellular networks) from noise limited radio systems (e.g. WLANs). Mange01 (talk) 22:37, 14 April 2010 (UTC)

Two references to german wikipedia[edit]

The list of different language versions of this article has German listed twice. Is this fine? I failed to find info on this in the help. Riichrd (talk) 22:16, 6 February 2011 (UTC)

One is noise in physics, and the other is current noise. It's not clear to me which one would be more relevant. Maybe someone who reads German better should decide. Dicklyon (talk) 22:51, 6 February 2011 (UTC)
I don't really read German but I gather de:Rauschen (Physik) is about noise (physics) more generally [which currently redirects to noise (electronics)] and de:Stromrauschen is just about electrical noise. I'd tend to think de:Stromrauschen is more relevant. Vadmium (talk) 00:07, 8 February 2011 (UTC).
I do read German and Vadmium's assessment is correct. I have removed the de:Rauschen (Physik) entry. Edit: Reverted removal after noticing that Noise (physics) is a redirect to this article. Nageh (talk) 08:53, 8 February 2011 (UTC)
(PS: Surprising that we don't have a general article on noise in physics. There is so much more to say than electro-magnetic noise in electronics. Nageh (talk) 09:06, 8 February 2011 (UTC))

Audible?[edit]

I dont know if this belongs here, but couldnt find anywhere more relevant. I present an anecdote only because of a lack of known terms for it: I will hear constant buzzing of electronics. I can her it change frequency during power surges. It was incredibly obvious during the days when CRT displays were everywhere. Going to places empty of such electronics, like a desert, would very obviously not have this noise.

If this is the place for this, then I think a section on audible electronic noise would be very useful here. If this isn't the right place for this, my apologies, though I would ask to be corrected and given the actual term for this. 74.132.249.206 (talk) 02:34, 15 November 2011 (UTC)

It sounds like you have an unusual electrical sense. Dicklyon (talk) 04:03, 15 November 2011 (UTC)
Several electronic components can produce high frequency sounds due to magnetic or electrostatic forces present in electronic devices, which put the components under mechanical resonance. In the case of old CRT monitors, the line output transformer is the dominant source for a high-frequency sound at a frequency of close to 16 kHz (the horizontal scan rate), which is generally audible for younger people.
No, this shouldn't go into this article (and it isn't noise, technically). Hope that helps, Nageh (talk) 19:06, 15 November 2011 (UTC)
Well, it's audible. Is there an article for these types of noise, including processor noise? 96.231.17.131 (talk) 18:22, 14 December 2012 (UTC)
I think we do have an article for that type of noise:
A few people have ears sensitive enough to hear magnetostriction noise (which is acoustic) at 15,734 Hz (for NTSC systems) or 15,625 Hz (for PAL systems) cathode ray tube#High-frequency audible noise. Many people have ears sensitive enough to hear magnetostriction noise at 60 Hz (US) or 50 Hz (Europe) in transformers directly connected to mains.
The ceramic capacitor#Microphony article also mentions a "reverse microphonic effect" that can produce acoustic noise, as wells as "microphonics" converting mechanical vibrations into unwanted electrical noise.
I imagine that some of our readers may want to know about the acoustic noise coming from some electronic devices, have no idea that it is called "magnetostriction", and end up here at this "Noise (electronics)" article.
What's a good way to tell those readers that maybe one of those other 3 articles may be what they are really looking for?
--DavidCary (talk) 02:33, 22 August 2014 (UTC)

Noise reduction[edit]

I think this page should refer to ways to reduce unwanted noise in a circuit. In electronics, some ways to reduce noise are: Faraday cage, avoiding ground loops, shielding cables, twisted-pair wiring, etc. Also, maybe there should be have a section describing how these noise signals are picked up and how these examples will eliminate the noise. For example, twisting two wires tightly together will decrease electromagnetic noise pick up from the loops between the two wires because the area between the two wires decreases to a minimum. In many sensitive circuits, there can be cross-talk between two wires if they are not shielded properly. It would be a good idea to expand on all of these noise reduction techniques. Another more sophisticated way to reduce 60 Hz noise from power lines is to send your signal through a notch filter that is set for 60 Hz using an Op-Amp. There are certain chips that can be purchased for tasks like this. This technique will amplify the wanted signal without amplifying the 60 Hz noise signal. Mcginnsc (talk) —Preceding undated comment added 16:37, 19 April 2012 (UTC).

These sound like good ideas, but what you are describing is more EMI prevention, rather than preventing noise intrinsic to a device. Maybe they would fit in better at Electromagnetic interference? And remember, be bold! GyroMagician (talk) 13:03, 21 April 2012 (UTC)
I see what your saying, but I think electromagnetic interference is just one part of electronic noise. What about examples like capacitive coupling between two resistors, ground loops, avoiding power loss through a bus lines, etc? I only think it's a good idea to give information like this in the article because I've ran into many problems from unwanted noise while designing circuits, and I'm sure I'm not the only one! I can't count how many times my circuit should have worked theoretically but didn't because of some of these noise issues. I think this page is more of a general topic on electronic noise and could give some ideas on how to avoid noise, while the Electromagnetic interference page goes into more depth of that idea. Maybe I'm wrong. Or maybe that page could be linked to this one when talking about electromagnetic noise. Thanks for the feedback. It's greatly appreciated! Mcginnsc (talk) —Preceding undated comment added 16:21, 24 April 2012 (UTC).
The problem with the recent addition is that none of the given noise techniques will have any effect on the fundamental noise processes that are listed in the article. Shielding doesn't minimized thermal noise; refrigeration will. I understand the common meaning of "noise", but I agree with GyroMagician's viewpoint. The techniques will work for electromagnetic interference, electromagnetic compatibility and some other forms of interference. Glrx (talk) 16:10, 27 April 2012 (UTC)
For starters this article is a little difficult to find. I typed in Noise and wikipedia sent me to the noise article, which is fine, but it should have links at the top instead of halfway down. As for this article I feel like an article titled Noise (electronics) should be an overview of noise in electronics. Someone searching for information on electronic noise may be looking for a variety of different things so the article shouldn't be limited to the fundamental generation of noise. With that I think the article should either be retitled or expanded to include many different concepts involving the creation and elimination of noise. Or maybe I just have the wrong concept of electronics noise, and a more formal definition is needed. Bradyjs bradyjs (talk) 14:32, 3 May 2012 (UTC)

Noise (electronics) edits[edit]

(transferred from user talk)

G'day, I hope that you are going to go back to the Noise (electronics) article and copyedit it, because what you reinstated is dreadful. Cheers YSSYguy (talk) 12:52, 3 June 2013 (UTC)

Partly you are right. The thoughts are to combine the new content - which is different from Electromagnetic compatibility - with the "Noise Reduction" section. Its not wrong now, i have to think maximum a few days. Difficult! The whole article, and even more, nearly all noise related article are NOT GOOD. A lot of work, hours, we will see if i start this. Tagremover (talk) 15:55, 3 June 2013 (UTC)
First version done. Tagremover (talk) 16:47, 3 June 2013 (UTC)

merge[edit]

I suggest merging noise generator into noise (electronics). Currently there seems to be a lot of overlap between the two articles -- both articles have descriptions of thermal noise, shot noise, avalanche noise, etc. Imagine a single article covering all three of (1) physical sources of noise, (2) techniques to minimize unwanted noise, and (3) techniques to deliberately amplify and collect "noise" as a noise generator. I suspect such an article will much shorter than the total length of 3 separate articles to cover the same topics, and so it simplifies things to cover them all together in one article. --DavidCary (talk) 02:58, 22 August 2014 (UTC)

I do not oppose the suggestion. I am looking at noise from another angle, that of a user. From that perspective, the electronic noise article is about interference with a message, whereas noise generation appears to be about generic messages of a known strength, to a user. Thus a noise generator could be used for calibration, for example, to test the sensitivity of a communications circuit. Thus merging of the articles involves explaining at least two different topics in the same article, notwithstanding the common sections. --Ancheta Wis   (talk | contribs) 04:00, 22 August 2014 (UTC)

I think they work best as separate topics. Yes, the noise generator articles talks about how various electronic devices and noise mechanisms can be used, but it's still a pretty separate topic. Dicklyon (talk) 04:33, 22 August 2014 (UTC)

I agree; two articles makes sense. Johnuniq (talk) 06:38, 22 August 2014 (UTC)
  • Oppose merge. Although intertwined, they are separate topics. Glrx (talk) 15:51, 25 August 2014 (UTC)
  • Oppose at this time. I don't see how merging will improve coverage. Weaving noise generator into this article is going to make things more complicated for contributers. Both articles need improvement. Noise (electronics) especially deserves attention as it is a high priority topic for three wikiprojects. Once we're further along we can have another look at this proposal. ~KvnG 14:24, 29 August 2014 (UTC)