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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)
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)
Kindly justify the points u think are errors. That touched my heart. -- Electron Kid 16:27, 18 December 2005 (UTC)
should read Frequency modulation (FM) (here the frequency of the carrier signal is varied in accordance to the instantaneous amplitude of the modulating signal) and Phase modulation (PM) (here the phase shift of the carrier signal is varied in accordance to the instantaneous amplitude of the modulating signal)
Kindly justify the points u think are errors. That touched my heart. -- Electron Kid 16:27, 18 December 2005 (UTC)
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)
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 really don't think it's unreasonable to expect and accept that some people will simply not have the level of education in the subject matter required to understand the article. That definitely doesn't mean the article should be dumbed-down. Then it would help ultimately no one. — Preceding unsigned comment added by 206.208.32.2 ( talk) 17:28, 13 May 2021 (UTC)
Somebody can explain modulation formats in a wireless/wireline agnostic way. --பராசக்தி 21:35, 23 November 2006 (UTC)
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)
There is two list of the digital modulation techniques. I think this section should be revised. —Preceding unsigned comment added by 189.27.3.193 ( talk) 17:20, 12 December 2007 (UTC)
I believe this chapter contradicts itself as it mentions digital modulation is ultimately analog (as it is), But the last (uncited) source claims it is not. — Preceding unsigned comment added by 187.189.247.68 ( talk) 01:41, 27 September 2019 (UTC)
Please vote at Talk:Eb/N0#Survey on which unit that should be used at Wikipedia for measuring Spectral efficiency. For background, see the discussion at Talk:Spectral_efficiency#Bit/s/Hz and at Talk:Eb/N0#Bit/s/Hz. Mange01 ( talk) 07:21, 16 April 2008 (UTC)
The article shows Analog, Digital, and Spread Spectrum as three types of modulation. Analog and Digital are summarized in the article, but Spread Spectrum is not. The article for Spread Spectrum should be summarized here to highlight the important details of that type of modulation. Also modulation in music is mentioned in the opening paragraph, but modulation in telecommunications is the subject of the article. A link or a brief explanation of how it is used in music should be shown. ( RobPSL ( talk) 02:50, 5 June 2008 (UTC))
It seems to me this article is very similar or identical in purpose and scope to the Amplitude modulation article. Could/should they be merged? -- 166.70.188.26 ( talk) 17:45, 30 June 2008 (UTC)
See discussion at Talk:Frequency modulation#Too many animations
The main article could be improved with a couple paragraphs on the history of modulation. Did it really start with telegraph wires that were turned into telephones? How did it differ in the later years, when radio broadcasting came to be the norm?
The main article contains the following sentence:
"Often a high-frequency sinusoid waveform is used as carrier signal to convey a lower frequency signal."
but doesn't explain the history or mathematics behind it. Why does the waveform have to be sinusoidal? Was that the easiest waveform to generate? What happens when some other waveform is used? Was there a spectacular failure or difficulty encountered by some early pioneer who tried a different waveform? Dexter Nextnumber ( talk) 03:08, 17 December 2009 (UTC)
Were there significant differences in the consumption of power between AM and FM in the 1920s and 1930s? I am curious about the expenses an early station director would have had to consider, to decide which kind of modulation he would have to authorize in order to run his business. Dexter Nextnumber ( talk) 03:16, 17 December 2009 (UTC)
I tried to remove the above illustration, but the removal was reverted. I don't see any motivatation of the illustration. It is hard to understand and shows DSB-SC AM, something not used in any application today. The carrier frequency should be much higher to make the illustration comprehensible, but anyway, DSB-SC is too academic and theoretical for this article. DSB-UC is the most common form of AM, and is already clearly illustrated in this article. Other common forms are QAM and SSB, but let's leave those for the AM article.
However, we need simple illustrations of the most common digital modulation schemes. Mange01 ( talk) 21:28, 21 March 2011 (UTC)
What does it mean to multiply two waves? 188.58.66.46 ( talk) 09:39, 5 March 2012 (UTC)
The two leading paragraphs in the introduction give the impression that there are two different definitions of modulation in telecommunications and electronics. Are there? If true, it should be sourced. If not, maybe the two paragraphs should be edited to emphasize that these are just different ways of viewing the modulation process. -- Chetvorno TALK 15:05, 8 February 2014 (UTC)
There is a tiny problem in the following sentence (shown in bold):
The sentence implies that "analog audio signal" can not be transmitted physically, and therefore needs to be carried in the carrier signal. However, analog audio signal is already a continuous-time signal (i.e. analog) which can be readily transmitted.
If what is meant by "analog audio signal" is sampled and quantized analog audio signal, then it isn't analog anymore, it is digital, i.e. the same as the first example; a digital bit stream.
A more clearer sentence would be:
78.162.13.181 ( talk) 13:00, 17 April 2014 (UTC)
I don't see the problem; that can be physically transmitted does not imply that the original signal cannot also be physically transmitted. Dicklyon ( talk) 03:11, 18 April 2014 (UTC)
1. Under "List of common analog modulation techniques", should "frequency modulation" and "phase modulation" be listed at the same level with "amplitude modulation" or they are actually a type of "angle modulation" technique?
2. "According to one definition of digital signal, the modulated signal is a digital signal. According to another definition, the modulation is a form of digital-to-analog conversion. Most textbooks would consider digital modulation schemes as a form of digital transmission, synonymous to data transmission; very few would consider it as analog transmission."
I'm not sure what this means and what is the relevance.
3. Should "Modulator and detector principles of operation" be "Modulator and demodulator principles of operation"?
4. "Non-coherent modulation methods do not require a receiver reference clock signal that is phase synchronized with the sender carrier wave. In this case, modulation symbols (rather than bits, characters, or data packets) are asynchronously transferred. The opposite is coherent modulation."
I'm not sure what the relevance of the above information with the section.
5. Should "OOK" be listed under "ASK" in the "List of common digital modulation techniques"?
6. "MSK is a particular case of the sub-family of CPM known as continuous-phase frequency-shift keying (CPFSK)".
If that is the case, "MSK" should be listed under "CPFSK".
7. "Pulse-width modulation (PWM) and Pulse-depth modulation (PDM)"
Why aren't they split on two lines?
8. Under "Analog-over-digital methods", shouldn't "ADPCM" be indented under "DCPM"?
ICE77 ( talk) 06:59, 14 June 2015 (UTC)
After explaining audio tones and modems for telephones, it seems to suggest that this is different for DSL, but doesn't say why it is different. The frequencies are different, and the modulation method may be different, but otherwise they are similar enough, both being modulated in some way. Gah4 ( talk) 00:19, 6 December 2015 (UTC)
Since I'm not sure if the below techniques fall under articles for 'Pulse Position Modulation' (if analog waveforms can be considered encoded data, with a clock/sample rate), or (Pulsed) 'Frequency Modulation', could pulse modulating voice using microwave transmitters possibly be included under the 'Miscellaneous modulation techniques' header?
/info/en/?search=Modulation#Miscellaneous_modulation_techniques
"Over the years, some have expressed concerns about the capability of communicating directly with humans by pulsed microwaves. In fact, earlier while studying microwave-induced auditory effects in human subjects, it was noticed that in addition to zip, click and knock sounds from exposure to single pulses of microwave radiation, short trains of rectangular microwave pulses are heard as chirps with tones corresponding to the pulse repetition frequencies [Guy et al., 1973, 1975]. It was also found that when the pulse generator was keyed manually such that each closing and opening of a push-button switch resulted in emitting a short rectangular pulse of microwave energy-transmitted digital codes (Morse code) were received and accurately interpreted by the targeted subject [Lin, 1978].
Also, soon after a system was setup for exploring the microwave auditory effect at the Walter Reed Army Institute of Research (WRAIR) [Sharp, et al., 1974], two of the principal investigators were able to demonstrate direct communication of simple speech via appropriate modulation of microwave energy [Justesen, 1975]. They tape-recorded each of the single-syllable words for digits between one and ten. The speech waveforms of each word were then converted to digital signals in such a fashion that each time an analog speech wave crossed the zero reference in the negative direction, a short pulse of microwave energy was emitted from the transmitter. By subjecting themselves to the exposure of 'speech modulated' microwave energy, the investigators reported the ability to hear, identify, and distinguish the word transmitted."
[1]
"Frey and Messenger (1973) demonstrated and Guy, Chou, Lin, and Christensen (1975) confirmed that a microwave pulse with a slow rise time is ineffective in producing an auditory response; only if the rise time is short, resulting in effect in a square wave with respect to the leading edge of the envelope of radiated radio-frequency energy, does the auditory response occur. Thus, the rate of change (the first derivative) of the wave form of the pulse is a critical factor in perception. Given a thermodynamic interpretation, it would follow the information can be encoded in the energy and 'communicated' to the 'listener'. Communication has in fact been demonstrated. A.Guy (Note 1), a skilled telegrapher, arranged for his father, a retired railroad telegrapher, to operate a key, each closure and opening of which resulted in radiation of a pulse of microwave energy. By directing the radiations as his own head, complex messages via the Continental Morse Code were readily received by Guy. Sharp and Grove (Note 2) found that appropriate modulation of microwave energy can result in direct 'wireless' and 'receiverless' communication of speech. They recorded by voice on tape each of the single-syllable words for digits between 1 and 10. The electrical sine-wave analogs of each word were then processed so that each time a sine wave crossed zero reference in the negative direction, a brief pulse of microwave energy was triggered. By radiating themselves with these 'voice modulated' microwaves, Sharp and Grove mere readily able to hear, identify, and distinguish among the 9 words."
[2]
[3]
References:
RrabEkim (
talk) 03:18, 6 October 2021 (UTC)
I added the following bullet point and sentence to the article, under the 'Miscellaneous modulation techniques' header:
RrabEkim ( talk) 04:44, 1 November 2021 (UTC)
The 'Pulse modulation methods' section:
/info/en/?search=Modulation#Pulse_modulation_methods
Does not currently include:
/info/en/?search=Pulse-frequency_modulation
RrabEkim (
talk) 20:50, 7 October 2021 (UTC)
I've added Pulse-frequency modulation (PFM) to the 'Pulse modulation methods' section.
RrabEkim (
talk) 20:59, 7 October 2021 (UTC)
Should a new article be created describing modulators, different types of modulators and modulator circuits? Or should that information be added under this article only. Alacris ( talk) 13:05, 21 March 2023 (UTC)
This
level-4 vital article is rated C-class on Wikipedia's
content assessment scale. It is of interest to the following WikiProjects: | ||||||||||||||||||||||||||||||||||||||
|
This article is substantially duplicated by a piece in an external publication. Please do not flag this article as a copyright violation of the following source:
|
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)
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)
Kindly justify the points u think are errors. That touched my heart. -- Electron Kid 16:27, 18 December 2005 (UTC)
should read Frequency modulation (FM) (here the frequency of the carrier signal is varied in accordance to the instantaneous amplitude of the modulating signal) and Phase modulation (PM) (here the phase shift of the carrier signal is varied in accordance to the instantaneous amplitude of the modulating signal)
Kindly justify the points u think are errors. That touched my heart. -- Electron Kid 16:27, 18 December 2005 (UTC)
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)
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 really don't think it's unreasonable to expect and accept that some people will simply not have the level of education in the subject matter required to understand the article. That definitely doesn't mean the article should be dumbed-down. Then it would help ultimately no one. — Preceding unsigned comment added by 206.208.32.2 ( talk) 17:28, 13 May 2021 (UTC)
Somebody can explain modulation formats in a wireless/wireline agnostic way. --பராசக்தி 21:35, 23 November 2006 (UTC)
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)
There is two list of the digital modulation techniques. I think this section should be revised. —Preceding unsigned comment added by 189.27.3.193 ( talk) 17:20, 12 December 2007 (UTC)
I believe this chapter contradicts itself as it mentions digital modulation is ultimately analog (as it is), But the last (uncited) source claims it is not. — Preceding unsigned comment added by 187.189.247.68 ( talk) 01:41, 27 September 2019 (UTC)
Please vote at Talk:Eb/N0#Survey on which unit that should be used at Wikipedia for measuring Spectral efficiency. For background, see the discussion at Talk:Spectral_efficiency#Bit/s/Hz and at Talk:Eb/N0#Bit/s/Hz. Mange01 ( talk) 07:21, 16 April 2008 (UTC)
The article shows Analog, Digital, and Spread Spectrum as three types of modulation. Analog and Digital are summarized in the article, but Spread Spectrum is not. The article for Spread Spectrum should be summarized here to highlight the important details of that type of modulation. Also modulation in music is mentioned in the opening paragraph, but modulation in telecommunications is the subject of the article. A link or a brief explanation of how it is used in music should be shown. ( RobPSL ( talk) 02:50, 5 June 2008 (UTC))
It seems to me this article is very similar or identical in purpose and scope to the Amplitude modulation article. Could/should they be merged? -- 166.70.188.26 ( talk) 17:45, 30 June 2008 (UTC)
See discussion at Talk:Frequency modulation#Too many animations
The main article could be improved with a couple paragraphs on the history of modulation. Did it really start with telegraph wires that were turned into telephones? How did it differ in the later years, when radio broadcasting came to be the norm?
The main article contains the following sentence:
"Often a high-frequency sinusoid waveform is used as carrier signal to convey a lower frequency signal."
but doesn't explain the history or mathematics behind it. Why does the waveform have to be sinusoidal? Was that the easiest waveform to generate? What happens when some other waveform is used? Was there a spectacular failure or difficulty encountered by some early pioneer who tried a different waveform? Dexter Nextnumber ( talk) 03:08, 17 December 2009 (UTC)
Were there significant differences in the consumption of power between AM and FM in the 1920s and 1930s? I am curious about the expenses an early station director would have had to consider, to decide which kind of modulation he would have to authorize in order to run his business. Dexter Nextnumber ( talk) 03:16, 17 December 2009 (UTC)
I tried to remove the above illustration, but the removal was reverted. I don't see any motivatation of the illustration. It is hard to understand and shows DSB-SC AM, something not used in any application today. The carrier frequency should be much higher to make the illustration comprehensible, but anyway, DSB-SC is too academic and theoretical for this article. DSB-UC is the most common form of AM, and is already clearly illustrated in this article. Other common forms are QAM and SSB, but let's leave those for the AM article.
However, we need simple illustrations of the most common digital modulation schemes. Mange01 ( talk) 21:28, 21 March 2011 (UTC)
What does it mean to multiply two waves? 188.58.66.46 ( talk) 09:39, 5 March 2012 (UTC)
The two leading paragraphs in the introduction give the impression that there are two different definitions of modulation in telecommunications and electronics. Are there? If true, it should be sourced. If not, maybe the two paragraphs should be edited to emphasize that these are just different ways of viewing the modulation process. -- Chetvorno TALK 15:05, 8 February 2014 (UTC)
There is a tiny problem in the following sentence (shown in bold):
The sentence implies that "analog audio signal" can not be transmitted physically, and therefore needs to be carried in the carrier signal. However, analog audio signal is already a continuous-time signal (i.e. analog) which can be readily transmitted.
If what is meant by "analog audio signal" is sampled and quantized analog audio signal, then it isn't analog anymore, it is digital, i.e. the same as the first example; a digital bit stream.
A more clearer sentence would be:
78.162.13.181 ( talk) 13:00, 17 April 2014 (UTC)
I don't see the problem; that can be physically transmitted does not imply that the original signal cannot also be physically transmitted. Dicklyon ( talk) 03:11, 18 April 2014 (UTC)
1. Under "List of common analog modulation techniques", should "frequency modulation" and "phase modulation" be listed at the same level with "amplitude modulation" or they are actually a type of "angle modulation" technique?
2. "According to one definition of digital signal, the modulated signal is a digital signal. According to another definition, the modulation is a form of digital-to-analog conversion. Most textbooks would consider digital modulation schemes as a form of digital transmission, synonymous to data transmission; very few would consider it as analog transmission."
I'm not sure what this means and what is the relevance.
3. Should "Modulator and detector principles of operation" be "Modulator and demodulator principles of operation"?
4. "Non-coherent modulation methods do not require a receiver reference clock signal that is phase synchronized with the sender carrier wave. In this case, modulation symbols (rather than bits, characters, or data packets) are asynchronously transferred. The opposite is coherent modulation."
I'm not sure what the relevance of the above information with the section.
5. Should "OOK" be listed under "ASK" in the "List of common digital modulation techniques"?
6. "MSK is a particular case of the sub-family of CPM known as continuous-phase frequency-shift keying (CPFSK)".
If that is the case, "MSK" should be listed under "CPFSK".
7. "Pulse-width modulation (PWM) and Pulse-depth modulation (PDM)"
Why aren't they split on two lines?
8. Under "Analog-over-digital methods", shouldn't "ADPCM" be indented under "DCPM"?
ICE77 ( talk) 06:59, 14 June 2015 (UTC)
After explaining audio tones and modems for telephones, it seems to suggest that this is different for DSL, but doesn't say why it is different. The frequencies are different, and the modulation method may be different, but otherwise they are similar enough, both being modulated in some way. Gah4 ( talk) 00:19, 6 December 2015 (UTC)
Since I'm not sure if the below techniques fall under articles for 'Pulse Position Modulation' (if analog waveforms can be considered encoded data, with a clock/sample rate), or (Pulsed) 'Frequency Modulation', could pulse modulating voice using microwave transmitters possibly be included under the 'Miscellaneous modulation techniques' header?
/info/en/?search=Modulation#Miscellaneous_modulation_techniques
"Over the years, some have expressed concerns about the capability of communicating directly with humans by pulsed microwaves. In fact, earlier while studying microwave-induced auditory effects in human subjects, it was noticed that in addition to zip, click and knock sounds from exposure to single pulses of microwave radiation, short trains of rectangular microwave pulses are heard as chirps with tones corresponding to the pulse repetition frequencies [Guy et al., 1973, 1975]. It was also found that when the pulse generator was keyed manually such that each closing and opening of a push-button switch resulted in emitting a short rectangular pulse of microwave energy-transmitted digital codes (Morse code) were received and accurately interpreted by the targeted subject [Lin, 1978].
Also, soon after a system was setup for exploring the microwave auditory effect at the Walter Reed Army Institute of Research (WRAIR) [Sharp, et al., 1974], two of the principal investigators were able to demonstrate direct communication of simple speech via appropriate modulation of microwave energy [Justesen, 1975]. They tape-recorded each of the single-syllable words for digits between one and ten. The speech waveforms of each word were then converted to digital signals in such a fashion that each time an analog speech wave crossed the zero reference in the negative direction, a short pulse of microwave energy was emitted from the transmitter. By subjecting themselves to the exposure of 'speech modulated' microwave energy, the investigators reported the ability to hear, identify, and distinguish the word transmitted."
[1]
"Frey and Messenger (1973) demonstrated and Guy, Chou, Lin, and Christensen (1975) confirmed that a microwave pulse with a slow rise time is ineffective in producing an auditory response; only if the rise time is short, resulting in effect in a square wave with respect to the leading edge of the envelope of radiated radio-frequency energy, does the auditory response occur. Thus, the rate of change (the first derivative) of the wave form of the pulse is a critical factor in perception. Given a thermodynamic interpretation, it would follow the information can be encoded in the energy and 'communicated' to the 'listener'. Communication has in fact been demonstrated. A.Guy (Note 1), a skilled telegrapher, arranged for his father, a retired railroad telegrapher, to operate a key, each closure and opening of which resulted in radiation of a pulse of microwave energy. By directing the radiations as his own head, complex messages via the Continental Morse Code were readily received by Guy. Sharp and Grove (Note 2) found that appropriate modulation of microwave energy can result in direct 'wireless' and 'receiverless' communication of speech. They recorded by voice on tape each of the single-syllable words for digits between 1 and 10. The electrical sine-wave analogs of each word were then processed so that each time a sine wave crossed zero reference in the negative direction, a brief pulse of microwave energy was triggered. By radiating themselves with these 'voice modulated' microwaves, Sharp and Grove mere readily able to hear, identify, and distinguish among the 9 words."
[2]
[3]
References:
RrabEkim (
talk) 03:18, 6 October 2021 (UTC)
I added the following bullet point and sentence to the article, under the 'Miscellaneous modulation techniques' header:
RrabEkim ( talk) 04:44, 1 November 2021 (UTC)
The 'Pulse modulation methods' section:
/info/en/?search=Modulation#Pulse_modulation_methods
Does not currently include:
/info/en/?search=Pulse-frequency_modulation
RrabEkim (
talk) 20:50, 7 October 2021 (UTC)
I've added Pulse-frequency modulation (PFM) to the 'Pulse modulation methods' section.
RrabEkim (
talk) 20:59, 7 October 2021 (UTC)
Should a new article be created describing modulators, different types of modulators and modulator circuits? Or should that information be added under this article only. Alacris ( talk) 13:05, 21 March 2023 (UTC)