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can anyone tell me how to find the phase constant?
It is also equal to the square root of Yl* Zl myclob 22:45, 13 April 2007 (UTC)
I am proposing merging into this article attenuation constant and phase constant. All three articles are likely to remain stubs as there is little more to say on any of them. They only stand a chance of being a decent article when taken together. There is also a very large number of alternative names for these quantities, it would be good if all the redirects where to point to the same place. SpinningSpark 14:11, 3 June 2008 (UTC)
In the “Copper Lines” section,in the clause: there are some decidedly non-linear effects I would like to suggest changing the phrase some decidedly non-linear effects to frequency dependant effects. The reason is that non-linear often means that there is a non-linear interaction of the signals leading to harmonic distortion and intermodulation distortion and I don't think that is what is meant. Constant314 ( talk) 02:36, 26 May 2010 (UTC)
I want to propose that the ‘’Copper lines’’ section be expanded to include a discussion of the propagation constant and characteristic impedance in the three frequency ranges. That would be high, intermediate and very low frequency including dc. High frequency is when ωC >> G and ωL >> R. Intermediate is when ωC >> G and R >> ωL. Low is when G >> ωC and R >> ωL. Constant314 ( talk) 12:53, 27 May 2010 (UTC)
it says "Losses in the dielectric depend on the loss tangent (tanδ) of the material, which depends inversely on the wavelength of the signal and is directly proportional to the frequency"
So, does the loss tangent depend inversely on the wavelength, which is what I think the language says and is wrong, I think,
or does the Losses in the dielectric depend inversely on the wavelength, which is what the following equation seems to say, and would be true if the loss tangent were more or less independent of frequency? Constant314 ( talk) 21:30, 12 November 2010 (UTC)
I don't see a problem with the two external links that I placed in the article, and which have been removed. The links comply with WP:EL. The fact there are adds on the web site does not appear to be an impedement to adding these links. The adds do not dominate the linked pages. In fact it is the content of the article, which dominates each article. In fact, I did not even notice the advertisements on these pages. Also, the information presented is in a different manner compared to this article. These may actually give a clearer explanation. Also the focus of one is microwave frequencies, while the focus of the other article is optical frequencies. Based on the above I am restoring the links. Especially since they comply with WP:EL. ---- Steve Quinn ( talk) 01:30, 4 February 2011 (UTC)
In the alternative names for Attenuation constant, I have placed "attenuation" in front of "coefficient" since I intend to merge Attenuation coefficient into this page. At present Absorption coefficient is merged into Attenuation coefficient, which is wrong. I will unmerge that first. In general, Absorption does not equal Attenuation. — Preceding unsigned comment added by Abmcdonald ( talk • contribs) 10:48, 20 January 2013 (UTC)
In
"It represents the change in phase per metre along the path travelled by the wave at any instant and is equal to real part of the angular wavenumber of the wave."
is the wavenumber a complex number?
I am not seeing any sources that define wave number as ω/c as claimed in this edit which I have reverted. I agree that the dispersion formula,
is correct, but sources usually treat as synonymous phase constant β and wave number k, as in this book for instance. ω/c is the "free space" wave number, or k0, so we could write the dispersion formula as,
The only source I found after a quick search that does not treat them as synonymous was this book which has wave number synonymous with propagation constant instead of phase constant, but that is still not the same as the claim put in the article. Spinning Spark 22:25, 23 February 2016 (UTC)
Near the start of the section, it says
This implies that in the present context, "angular wave number" refers to the complex wave number. So far, so good.
But in the next line, we have
The way the sentence is expressed, it suggests that k is the "angular wave number". This would imply that k can be complex and β = Re(k). Yet the formula forces k to be real, because the other two terms are real.
I fixed this, but maybe there is a better fix. 178.39.122.125 ( talk) 16:47, 9 February 2017 (UTC)
Later in the section it says:
The problem here is twofold:
1) Earlier in the section, the relation is stated unconditionally, without mentioning that there will later be a restriction.
2) Furthermore, this relation is presented as the definition of , i.e. the phase constant is synonymous with the (real) wavenumber of plane waves in the medium. The relation is not presented as a theorem, approximation, or observation. So it's hard to see how they could ever be different, or what criteria a person could apply to determine that they are different.
Of course, there is a difference: the wave number is a property of a wave, whereas the propagation constant is a property of a medium. But I don't see how this can be used to drive a wedge between them. 178.39.122.125 ( talk) 17:20, 9 February 2017 (UTC)
References
The following paragraph from the section "Phase constant" seems to be "generalities" from quantum mechanics that are almost out of place here. Why is it relevant to mention the momentum of a photon at this point? It doesn't seem to tie into anything else.
I also wonder if this is even true.
Everyone knows the relation , where k is the wavenumber of a "free" photon or one that has explicit interactions with quantum particles -- in any case, at a very fundamental, atomwise level. On the other hand, β takes into account the material properties of the medium in a kind of summarized way, like Maxwell's equation in a medium.
Can we even mix these two levels? Looking at the two references, it appears that the relationship with β is not standard at all, but is being speculatively proposed by the authors of the two papers. Yet it is hidden here in the Wikipedia article behind a fairly bland presentation, which does not brag about the two papers.
Can an expert sort this out? 129.132.208.37 ( talk) 23:15, 9 February 2017 (UTC)
References
{{
cite journal}}
: Cite journal requires |journal=
(
help)CS1 maint: multiple names: authors list (
link)
![]() | This article is rated C-class on Wikipedia's
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can anyone tell me how to find the phase constant?
It is also equal to the square root of Yl* Zl myclob 22:45, 13 April 2007 (UTC)
I am proposing merging into this article attenuation constant and phase constant. All three articles are likely to remain stubs as there is little more to say on any of them. They only stand a chance of being a decent article when taken together. There is also a very large number of alternative names for these quantities, it would be good if all the redirects where to point to the same place. SpinningSpark 14:11, 3 June 2008 (UTC)
In the “Copper Lines” section,in the clause: there are some decidedly non-linear effects I would like to suggest changing the phrase some decidedly non-linear effects to frequency dependant effects. The reason is that non-linear often means that there is a non-linear interaction of the signals leading to harmonic distortion and intermodulation distortion and I don't think that is what is meant. Constant314 ( talk) 02:36, 26 May 2010 (UTC)
I want to propose that the ‘’Copper lines’’ section be expanded to include a discussion of the propagation constant and characteristic impedance in the three frequency ranges. That would be high, intermediate and very low frequency including dc. High frequency is when ωC >> G and ωL >> R. Intermediate is when ωC >> G and R >> ωL. Low is when G >> ωC and R >> ωL. Constant314 ( talk) 12:53, 27 May 2010 (UTC)
it says "Losses in the dielectric depend on the loss tangent (tanδ) of the material, which depends inversely on the wavelength of the signal and is directly proportional to the frequency"
So, does the loss tangent depend inversely on the wavelength, which is what I think the language says and is wrong, I think,
or does the Losses in the dielectric depend inversely on the wavelength, which is what the following equation seems to say, and would be true if the loss tangent were more or less independent of frequency? Constant314 ( talk) 21:30, 12 November 2010 (UTC)
I don't see a problem with the two external links that I placed in the article, and which have been removed. The links comply with WP:EL. The fact there are adds on the web site does not appear to be an impedement to adding these links. The adds do not dominate the linked pages. In fact it is the content of the article, which dominates each article. In fact, I did not even notice the advertisements on these pages. Also, the information presented is in a different manner compared to this article. These may actually give a clearer explanation. Also the focus of one is microwave frequencies, while the focus of the other article is optical frequencies. Based on the above I am restoring the links. Especially since they comply with WP:EL. ---- Steve Quinn ( talk) 01:30, 4 February 2011 (UTC)
In the alternative names for Attenuation constant, I have placed "attenuation" in front of "coefficient" since I intend to merge Attenuation coefficient into this page. At present Absorption coefficient is merged into Attenuation coefficient, which is wrong. I will unmerge that first. In general, Absorption does not equal Attenuation. — Preceding unsigned comment added by Abmcdonald ( talk • contribs) 10:48, 20 January 2013 (UTC)
In
"It represents the change in phase per metre along the path travelled by the wave at any instant and is equal to real part of the angular wavenumber of the wave."
is the wavenumber a complex number?
I am not seeing any sources that define wave number as ω/c as claimed in this edit which I have reverted. I agree that the dispersion formula,
is correct, but sources usually treat as synonymous phase constant β and wave number k, as in this book for instance. ω/c is the "free space" wave number, or k0, so we could write the dispersion formula as,
The only source I found after a quick search that does not treat them as synonymous was this book which has wave number synonymous with propagation constant instead of phase constant, but that is still not the same as the claim put in the article. Spinning Spark 22:25, 23 February 2016 (UTC)
Near the start of the section, it says
This implies that in the present context, "angular wave number" refers to the complex wave number. So far, so good.
But in the next line, we have
The way the sentence is expressed, it suggests that k is the "angular wave number". This would imply that k can be complex and β = Re(k). Yet the formula forces k to be real, because the other two terms are real.
I fixed this, but maybe there is a better fix. 178.39.122.125 ( talk) 16:47, 9 February 2017 (UTC)
Later in the section it says:
The problem here is twofold:
1) Earlier in the section, the relation is stated unconditionally, without mentioning that there will later be a restriction.
2) Furthermore, this relation is presented as the definition of , i.e. the phase constant is synonymous with the (real) wavenumber of plane waves in the medium. The relation is not presented as a theorem, approximation, or observation. So it's hard to see how they could ever be different, or what criteria a person could apply to determine that they are different.
Of course, there is a difference: the wave number is a property of a wave, whereas the propagation constant is a property of a medium. But I don't see how this can be used to drive a wedge between them. 178.39.122.125 ( talk) 17:20, 9 February 2017 (UTC)
References
The following paragraph from the section "Phase constant" seems to be "generalities" from quantum mechanics that are almost out of place here. Why is it relevant to mention the momentum of a photon at this point? It doesn't seem to tie into anything else.
I also wonder if this is even true.
Everyone knows the relation , where k is the wavenumber of a "free" photon or one that has explicit interactions with quantum particles -- in any case, at a very fundamental, atomwise level. On the other hand, β takes into account the material properties of the medium in a kind of summarized way, like Maxwell's equation in a medium.
Can we even mix these two levels? Looking at the two references, it appears that the relationship with β is not standard at all, but is being speculatively proposed by the authors of the two papers. Yet it is hidden here in the Wikipedia article behind a fairly bland presentation, which does not brag about the two papers.
Can an expert sort this out? 129.132.208.37 ( talk) 23:15, 9 February 2017 (UTC)
References
{{
cite journal}}
: Cite journal requires |journal=
(
help)CS1 maint: multiple names: authors list (
link)