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Old August 29th 03, 09:11 PM
Dr. Slick
 
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"Tarmo Tammaru" wrote in message ...
Why didn't you do the gamma for a shorted line using your formula? I think
you settled on (Zl - Z0*)/(Zl + Zo). For Zl = 0 this comes to -Z0*/Z0,
which, for Zo having phase angle b equates to -1 at angle(-2b).


Agreed. This doesn't prove anything, does it?


This is in more detail of what ACF do:

1. Normalize the RC to (Zn -1)/(Zn +1)
2. Let's say we agree that for biggest magnitude, this has to be in the left
hand plane.
3. Draw a vector for Zn = a at -135 deg
4. Draw vectors for Zn - 1 and Zn +1. Note that these 3 vectors have the
same y coordinate.
5. You now can draw two triangles with the corners at 0, Zn, and Zn -1 for
one, and 0, Zn, and Zn+1 for the other.
6. Solve for Zn+/-1 in terms of "a"
7. By plane geometry the magnitude of, of Zn -1=
SQRT(1 + a^2 + aSQRT(2))
8. The magnitude of Zn +1 is
SQRT(1 + a^2 - aSQRT(2))
9. Square both sides of the equation, and gamma^2=
(1 + a^2 + aSQRT(2))/(1 + a^2 - aSQRT(2))
10 This equates to 1 + (2SQRT(2))/((a + 1/a) - SQRT(2))
11 |Gamma| max occurs when (a + 1/a) is a minimum, which is 2 at a=1.
12|Gamma| max is 1 + SQRT(2)

They anticipate people being concerned about |Gamma| 1 and later come up
with a formula for time average power. I don't know that looking at it is
going to give anybody any insight, but for this is what they end up with ( I
am typing CM for Gamma):

P= (1/2)Go|V+|^2e**(-2az)[1 - |CM|^2 +2(Bo/Go)Im(CM)]

Remember, z is distance from the load.

Tam/WB2TT



ok, you've done a nice job of copying the text you sent me.

They also mention that the normalized load impedance Zn=Zr/Zo does
NOT have the same angle as Zr because Zo is complex in the general
case.

"They anticipate people being concerned about |Gamma| 1 and later come up
with a formula for time average power."


Really? Could you tell us more about that? Could you email me
more pages, especially the one that has Eq. 5.2b?



Slick