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#1
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Richard Clark wrote:
As for the math, you will find it by the reams, once you've been overwhelmed with the arcana of hyperbolic descriptions of a novel physics that have to proceed its proof. A scattering parameter analysis, described in HP Application Note 95-1 (available on the web) is ideal for analyzing what happens at a match point in a typical ham radio antenna system. b1 = s11(a1) + s12(a2) b2 = s21(a1) + s22(a2) b1 is the net forward voltage, b2 is the net reflected voltage a1 is the incident forward voltage, a2 is the incident reflected voltage Quoting from HP AN 95-1: Another advantage of s-parameters springs from the simple relationship between the variables a1, a2, b1, and b2, and various power waves: |a1|^2 = Power incident on the input of the network. (forward power incident on the match point) |a2|^2 = Power reflected from the load. |b1|^2 = Power reflected from the input port of the network. (power reflected from the match point back toward the source) |b2|^2 = Power incident on the load. The previous four equations show that s-parameters are simply related to power gain and mismatch loss, quantities which are often of more interest than the corresponding voltage functions. |s11|^2 = Power reflected from the network input divided by power incident on the network input |s22|^2 = Power reflected from the network output divided by power incident on the network output |s21|^2 = Power delivered to a Z0 load divided by power available from a Z0 source |s12|^2 = Reverse transducer power gain with Z0 load and source End quote. b2 is the voltage reflected back toward the source and b2 = s21(a1) + s22(a2) It should be obvious that b2 cannot be zero unless there exists total destructive interference between s21(a1) and s22(a2), i.e. s21(a1) is equal in magnitude and opposite in phase to s22(a2). -- 73, Cecil http://www.qsl.net/w5dxp -----= Posted via Newsfeeds.Com, Uncensored Usenet News =----- http://www.newsfeeds.com - The #1 Newsgroup Service in the World! -----== Over 100,000 Newsgroups - 19 Different Servers! =----- |
#2
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On Sun, 23 May 2004 10:06:15 -0500, Cecil Moore
wrote: Richard Clark wrote: As for the math, you will find it by the reams, once you've been overwhelmed with the arcana of hyperbolic descriptions of a novel physics that have to proceed its proof. A scattering parameter analysis,... arcana deleted as an obviously fulfilled prophecy. |
#3
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Richard Clark wrote:
wrote: A scattering parameter analysis,... arcana deleted as an obviously fulfilled prophecy. Richard, you are the only technical person I know of who ever considered s-paramater analysis to be a secret or mystery. It is one of the more technically popular methods of analysis, ideally suited to transmission line analysis. -- 73, Cecil http://www.qsl.net/w5dxp -----= Posted via Newsfeeds.Com, Uncensored Usenet News =----- http://www.newsfeeds.com - The #1 Newsgroup Service in the World! -----== Over 100,000 Newsgroups - 19 Different Servers! =----- |
#4
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Cecil Moore wrote:
Richard Clark wrote: As for the math, you will find it by the reams, once you've been overwhelmed with the arcana of hyperbolic descriptions of a novel physics that have to proceed its proof. A scattering parameter analysis, described in HP Application Note 95-1 (available on the web) is ideal for analyzing what happens at a match point in a typical ham radio antenna system. b1 = s11(a1) + s12(a2) b2 = s21(a1) + s22(a2) b1 is the net forward voltage, b2 is the net reflected voltage a1 is the incident forward voltage, a2 is the incident reflected voltage Quoting from HP AN 95-1: Another advantage of s-parameters springs from the simple relationship between the variables a1, a2, b1, and b2, and various power waves: |a1|^2 = Power incident on the input of the network. (forward power incident on the match point) |a2|^2 = Power reflected from the load. |b1|^2 = Power reflected from the input port of the network. (power reflected from the match point back toward the source) |b2|^2 = Power incident on the load. The previous four equations show that s-parameters are simply related to power gain and mismatch loss, quantities which are often of more interest than the corresponding voltage functions. |s11|^2 = Power reflected from the network input divided by power incident on the network input |s22|^2 = Power reflected from the network output divided by power incident on the network output |s21|^2 = Power delivered to a Z0 load divided by power available from a Z0 source |s12|^2 = Reverse transducer power gain with Z0 load and source End quote. b2 is the voltage reflected back toward the source and b2 = s21(a1) + s22(a2) It should be obvious that b2 cannot be zero unless there exists total destructive interference between s21(a1) and s22(a2), i.e. s21(a1) is equal in magnitude and opposite in phase to s22(a2). -- 73, Cecil http://www.qsl.net/w5dxp Richard is right, There is the first ream! Sorry, I'm a bit pippish today.......... - Mike KB3EIA - |
#5
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Mike Coslo wrote:
Richard is right, There is the first ream! Sorry, I'm a bit pippish today.......... Ignorance of s-parameter analysis, like ignorance of the Smith Chart, is not a mortal sin. -- 73, Cecil http://www.qsl.net/w5dxp -----= Posted via Newsfeeds.Com, Uncensored Usenet News =----- http://www.newsfeeds.com - The #1 Newsgroup Service in the World! -----== Over 100,000 Newsgroups - 19 Different Servers! =----- |
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