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noisy
Singapore
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 Posted - 12/21/2004 : 06:46:26 AM
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| is it possible to directly plot the s parameters on smith chart? what i have seen some ppl do is that they converted to z parameters then plot. |
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noisy
Singapore
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Posted - 12/22/2004 : 07:26:00 AM
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| anyone can help? need to know urgently... thank you... |
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forestan
China
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Posted - 12/23/2004 : 9:31:19 PM
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Origin can plot smith chart using z parameters directly, if you have the s parameters rather than z parameters, you can also plot it, some conversions are needed. I take an example to explain it.
Suppose you have two columns data of s parameters in worksheet:
SparaX(X) SparaY(Y)
0.5 0.5
0.4 0.2
0.75 0.25
0.2 0.4
Step1: convert rectangle coordinates into polar coordinates:
Add two columns named Mag, Angel
Choose Column Mag, Right Click ¡°Set column Values¡¡±, input the formula : sqrt(col(SParaX)*col(SParaX) + col(SParaY)*col(SParaY))
Choose Column Angel, Right Click ¡°Set column Values¡¡±, input the formula: atan(col(SParaY)/col(SParaX)) , and set this column as ¡°Y¡±.
Now Worksheet looks like this:
SparaX(X1) SparaY(Y1) Mag(X2) Angel(Y2)
0.5 0.5 0.70711 45
0.4 0.2 0.44721 26.56505
0.75 0.25 0.79057 18.43495
0.2 0.4 0.44721 63.43495
Step2: plot smith chart.
Choose column Mag and Angel, click plot->smith chart, now a smith chart will show, but the graph is not we want.
Step3: Click the button with smith chart icon at right top of the smith chart window, a configuration window will show.
Click the button ¡°Reinterpret Data as Mag/Angel¡±, now the smith chart is just what you want.
And, you may notice that two columns(column Mag1 and Angel1) are inserted, they represents Z parameters data of the smith chart.
SparaX(X1) SparaY(Y1) Mag1(X2) Angel1(Y2) Mag(X3) Angel(Y3)
0.5 0.5 1 2 0.70711 45
0.4 0.2 2 1 0.44721 26.56505
0.75 0.25 3 4 0.79057 18.43495
0.2 0.4 1 1 0.44721 63.43495
Edited by - forestan on 12/23/2004 9:35:24 PM |
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noisy
Singapore
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Posted - 12/24/2004 : 1:22:06 PM
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| thanks very much forestan, i tried it and it works... |
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Plotting S Parameters on Smith Chart