Talk:Baseband

message: :Yes, it does. Although we don't have that piece of information in an article so far as I can tell. See Ethernet and IEEE 802.3. -Splashtalk 17:54, 14 February 2006 (UTC)
replies: text: Not necessarily.  The orignal Ethernet used "Manchester coding", which can be viewed as shifting the theoretical 5 MHz baseband of 10 Mbps data up to a carrier frequency of 10 MHz, so the band occupied can be as narrow as 5 to 15 MHz.  Due to AC coupling with capacitors and/or transformers at various points, moving the peak of the data spectrum up from 0 to 10 MHz is helpful. This, however, is but one physical implementation of Ethernet.  Others such as 802.11 shift it up to RF, of course. Dicklyon 16:30, 19 August 2006 (UTC)

text: By definition, Ethernet uses baseband signalling.  It might be that some statements in the article are wrong.  The important one being that the frequency spectrum goes close to zero.  Gah4 (talk) 22:12, 7 January 2019 (UTC)
thread_title: Does ethernet use baseband signaling?

message: Let's work on a good opening sentence and definition (current version uses "comprises" in the typical incorrect way, and doesn't get to the point very specifically).  It would be good to at least admit that any kind of Fourier analysis gives negative frequencies, too.  For real signals, these are just reflections of the positive, not new information, so they are conventionally ignored.  And the "RF" spectrum needs to reference double sideband and/or single-sideband modulation to explain where this comes from. I'll see if I can help.  Please comment on my attempts. Dicklyon 16:30, 19 August 2006 (UTC)
thread_title: Intro

message: What combination of idiots wrote this article?  It makes no sense!  To be clear, I understand the topic now, but only because I went back to the VERY FIRST draft of this article from 2002 (http://en.wikipedia.org/w/index.php?title=Baseband&oldid=71326)!!!  That at least was a clear explanation, especially if read alongside the wikipedia articles for Band and Modulation.  I'm afraid to help edit the article though, because I have no idea what the hell the useless drivel on the current version means.
Mmurfin (talk) 20:14, 15 August 2010 (UTC)
thread_title:  Useless Article 

message: I disagree, I see some value here. Go around the web and search for something that connects "Bandwidth" and e.g. "Ethernet".  There is so little out there that even many engineers get so confused about something so basic as to claim that an Ethernet signal has no frequency spectrum because it's digital. Granted, it's something engineered once per decade or so, but not digging into this is like not explaining how things work because we're not supposed to understand the guts of a Tamagochi like they used to understand the guts of a spring-driven toy car. And, by the way, can anybody add the real-world (as opposed to information-theory or whatever) spectrum bandwidths of the various Ethernet signals? It' a bit like not mentioning that swimming is a form of locomotion (go see! :-P ) Spamhog (talk) 22:54, 1 December 2010 (UTC)
replies: text: In the case of many signals, it isn't useful to give one number as bandwidth.  You really need a power spectrum, how much power is transmitted at which frequency.  In the case of coaxial ethernet, it gets more complicated. While the data signal might fit in a 5MHz to 15MHz band, collision detection is done it DC, that is, close to 0Hz. The signal on the cable is not AC coupled, and the average DC voltage, after filtering, is used for collision detection.  It might be that between 1kHz and 5kHz that you could squeeze in some other signal.  Twisted-pair ethernet is transformer coupled, and so can't go down, or even close, to 0Hz. Gah4 (talk) 21:55, 28 March 2017 (UTC)
thread_title:  Not So Useless, and btw, what's the frequency bandwidth of Ethernet? 

message: Isn't the definition of baseband 'the signal you are trying to transmit'? Maybe add a quick explanation for the lay person, or an example, like: "In AM radio, the baseband includes the announcer's voice. The baseband is then modulated with the carrier frequency, which is the frequency on the radio dial, and then demodulated so that a voice is heard at the receiver." 
71.139.176.47 (talk) 19:35, 12 December 2012 (UTC)
replies: text: I cannot agree more with this statement.  Although replacing the entire article with this talk entry would be a large net improvement, simply offering the above explanation as the first paragraph would at least allay the offensive nature of this article to date.  5000+ people a month are being victimized by this academic fappery.  I try not to attribute malice to that which can be explained by the innocent bloviation that comes naturally to experts but articles this bad cause me to wonder if I'm being naive. Allenc28 (talk) 05:56, 13 July 2015 (UTC)
thread_title:  What is baseband? 

message: Transmission of signal with infinite bandwidth is called the basband transmission. A single signal transmitted over the transmission line occupies all the bandwidth of the transmission line. A digital pulse transmitted without modulation occupies infinite bandwidth.
Aursani (talk) 13:03, 12 June 2015 (UTC)
replies: text: While that sounds very intelligent, it means absolutely nothing to a person with no prior knowledge in this subject.  I came here for a refresher and after attempting to decipher this article, I am now absolutely confused.  The average non-engineer is not going to be able to make sense of "infinite bandwidth".  I cannot get much out of this article as it is currently written.  Why is it that I can go on YouTube and watch 1 or 2 videos and understand this topic completely, yet I cannot do anything with this source of "information"?  That is an important question that should be address if WP is going to have any value to casual readers. And yes, it does read like a low-quality textbook - which explains why students have such a difficult time with this topic.  Perhaps a re-write with better diagrams would help? Good writing should inform, not confuse the reader. 73.6.96.168 (talk) 04:25, 4 March 2021 (UTC)
thread_title:  Meaning of Baseband 

message: In my experience and opinion, a baseband signal is a signal that is centered at zero (f = 0) when viewing the two-sided (positive and negative) spectrum. It doesn't really have anything to do with bandwidth, as stated in the article. 
It is true that when one needs to modulate a signal, the carrier frequency must be chosen based on the bandwidth of the baseband signal and is usually much larger than the bandwidth, but this is a consequence of modulation. 
Yates (talk) 16:27, 8 October 2016 (UTC)
replies: text: Just reading the first sentence" Baseband is a signal that has a very narrow and near-zero frequency range, raises questions to me.  First of all, very narrow relative to what?  1000baseT, that is, gigabit ethernet, is baseband, though with a bandwidth over 100MHz.  And how close does it get to 0Hz?  Not very.  Seems to me that in actual use, a signal is baseband if its bandwidth is much wider than the frequency of the lower end of the band.  That is true for wide (say 10MHz or more) and narrow band signals.   The result is that there isn't spectral space for another (frequency shifted) version of the signal at lower frequencies.  There might be room for other signals, though. Gah4 (talk) 21:44, 28 March 2017 (UTC)
replies: text: I was about to say something about this, but it seems that I already did.  But "narrow" is always relative to something. The available frequency spectral space increases as faster transistors become available for low prices. Narrow isn't as narrow as it used to be. Gah4 (talk) 22:17, 7 January 2019 (UTC)
thread_title:  Definition of Baseband 

message: To me, baseband can mean centered at zero, or modulated such that the bandwidth extends essentially to zero (like baseband Ethernet).  I'll look for sources... This book might be useful, discussing various "line codes" including Manchester encoding, which don't quite go down to DC. Dicklyon (talk) 00:00, 8 January 2019 (UTC)
replies: text: I think that sounds closer than the current article.  It now seems, even with removal of "narrow" to suggest narrowness.  It says non-zero near f=0Hz, but 10G Ethernet is going to be non-zero up to somewhere in the GHz range.  If there are significant frequency components near, relatively, to zero it is baseband.   OK, the bottom of the traditional US TV band is channel 2 at 54 to 60MHz, a nice representative non-baseban signal.  The bottom of the spectral range is 9 times the bandwidth.  Is that a reasonable transition point?  Gah4 (talk) 09:03, 10 January 2019 (UTC)
thread_title: A possible resolution

message: It seems to me that Signal that has a very narrow frequency range near zero leaves out what very narrow is relative to, and also near zero leaves out how near.  This question comes up in real baseband signals. Start with traditional phones, which are spec'ed as 300Hz to 3400Hz.  OH, 3100Hz is pretty narrow, but 300Hz is a ways from zero. For an actual real case, traditional CATV put broadcast TV frequencies into a coaxial cable, so down to 54MHz.  Then later there was need for an uplink for pay-TV cable boxes, so they found space below 54MHz, to add it.  The cable system amplifiers have to amplify both directions, so have to separate out the two directions first. Because filters are imperfect, you can't get all that close. In any case, broadband CATV has plenty of room below. In any case, baseband rarely gets close to zero, and rarely is narrow. Gah4 (talk) 20:11, 11 August 2020 (UTC)
thread_title:  ''Signal that has a very narrow frequency range near zero'' 

message: To attempt to answer some of the questionss about this sort of slippery topic.
I have looked at the web for a better definition and so far haven't found one so I'm going to try for a 'more rigorous' definition of baseband and maybe an additional section should be added to appeal to engineers, physicists, and mathematicians. I don't think a perfectly rigorous definition is possible so we resort to some logic and an admittedly heuristic definition.
OK so the first problem is the very first figure in the article as it is, has no figure designator and it needs to be referred to in what should be added to this page. Lets call it Fig. 1 here.
OK so Fig. 1 is actually a spectrum for an analytic signal for which a good wiki article exists. So then to start this new 'more rigorous' heuristic section we must identify Fig 1 as the spectrum of an imaginary (complex or analytic) signal and redraw an additional version as the amplitude spectrum of a real signal, such spectrum as an even function adding its mirror image in a new figure. Then explain that the purpose of an analytic signal is to ignore negative frequencies of real signals for arriving at simpler depictions and analyses as in Fig 1.
OK so then we have an amplitude spectrum which is an even function which is a necessary but not sufficient attribute of a baseband signal. In addition to being an even function, every frequency point in the supported spectral domain has one and exactly one nonzero alias at its negative frequency, of identical magnitude. This works for all forms of modulation except SSB.
So then to try to deal with the SSB case we can add that for a baseband as distinct from its SSB form the spectral third moment about the second moment, is of similar magnitude as the second moment about the mean frequency (zero). This works except for extremely narrowband SSB signals e.g. sinusoids which carry no information beyond steady state frequency and phase. So if we have a spectral standard deviation  \omega _\sigma = \left[ \int_{-\infty}^\infty \omega^2\,F(\omega )\,\mathrm{d}\omega. \right]^{1/2}  
and define
\omega _\lambda = \left[ \int_{-\infty}^\infty \frac{(\omega - \omega _\sigma)^2}{2}\,F(\omega)\,\mathrm{d}\omega. \right]^{1/2}
then if 
 \frac{1}{5} < \frac{\omega _\lambda}{\omega _\sigma} < 5 
this would be an arbitrary exclusion of narrowband SSB signals
So then we verbally exclude narrowband SSB signals such as sinusoids. This final condition being strictly logical regrettably.
The 'regrettability' arises from the fact that a SSB modulation of a sinusoid is another pure sinusoid which has no feature described as baseband. So we have to apply this last attempt using the above equations to actual information bearing signals and any of their modulated representations, which as quasi-stochastic would only be characterised in the frequency domain with spectral density as opposed to a Fourier transform amplitude.
Comments welcome. 
 — Preceding unsigned comment added by Groovamos (talk • contribs) 23:48, 7 January 2022 (UTC)
replies: text: We're writing an encyclopaedia for a general readership here, not a textbook.  Why do you even think that a formal mathematical definition is required?  Baseband is a straightforward, simple, basic concept that can be stated quite adequately in words.  There's no way that any of that is going in the article, especially the very arbitrary last bit, in the absence of reliable sources backing it up.  Even then, I would probably be against it – introducing difficult mathematics for our readers when it is not necessary to do so.  Even my textbook from university (Goodyear, Signals and Information), which is chocked full of integrals of spectral densities and the like throughout, does not feel the need for such a formal definition of baseband. SpinningSpark 10:02, 8 January 2022 (UTC)

text: That has not been the opening sentence of the article for five months.  The earlier discussions are now completely out of date. SpinningSpark 22:14, 8 January 2022 (UTC)
thread_title:  A way forward from all of the questions about the rigor or clarity and accuracy of this article 

message: The current Short description  is too long and needs to be shorted per WP:SDSHORT and formatted correctly per WP:SDFORMAT. Two attempts to resolve this have just been reverted rather than improved. Please attempt to improve the SD — GhostInTheMachine talk to me 22:06, 16 June 2022 (UTC)
replies: text: Too long is preferable to wrong.  This is an encyclopaedia, not online scrabble.  Also, there is an interesting conversation going on at Talk:Waveguide/Archive 1#Short description – we cannot find views or examples of where an over-long SD has actually caused a display problem. SpinningSpark 22:14, 16 June 2022 (UTC)
replies: text:  Trying to improve an article is generally the best way forward. See WP:SDSHORT, WP:SDFORMAT, WP:SDNOTDEF  — GhostInTheMachine talk to me 22:25, 16 June 2022 (UTC)
replies: text: As I teach the subject, to electronics engineers and technicians, I did some editing of the article for clarification. The opening line is fine I feel. The rest of the article seems a bit broad with the inclusion of RF modulation using baseband signals, however, it just passes for relevance. I agree that as soon as you put mathematics into what can be described using words, it alienates most of the reading population, so during my lessons in RF Modulation, transmission and reception, I rarely use mathematics and certainly not for an encyclopaedic article, but that's just me. --Read-write-services (talk) 11:37, 17 June 2022 (UTC)

text: I've started a central discussion at Wikipedia_talk:Short_description#Too-short_descriptions ~Kvng (talk) 15:45, 20 June 2022 (UTC)
thread_title:  Short description 

message: It seems that the article Broadband is now only about high-speed internet, and lost is the application to radio (well, TV) transmission and reception, and especially the IF strip required for such receivers. When the bandwidth is large compared to the frequency, and that would be IF for many receivers, it complicates the design. That term then continued on into data communications, but now the original use is lost! Gah4 (talk) 04:34, 2 May 2023 (UTC)
thread_title:  Broadband