Hi Tom,
as far as I am concerned, your observations are rights only if we are
talking about real quantities. If you have a load that is complex then
you obtain perfect matching (there is no reflection) only if Z0 is not
equal to Zin but it is the conjugate of Zin. If you remember, this is
the same condition valid for the maximum power transferring when the
load in complex. Do you agree with these considerations?

Regards,

Camelot



I'm not sure where you got it, but the formula with the complex
conjugate is NOT correct! The formula without complex conjugate is
correct, for complex Z and Z0, both.

That the formula using the complex conjugate is incorrect is trivial
to see: consider that a line terminated in a load equal to the line's
characteristic impedance (be it purely resistive, or complex) has no
reflection. That is, if load Z = Z0, there is no reflection. Then if
Z0 is complex and has a non-zero reactive component, your formula
yields S11 which is not zero, for a line which is terminated to have
no reflection. As far as I am concerned, that would be incorrect.
The original formula, without complex conjugate, yields the correct
answer for this case. Can you come up with a case where it is
incorrect?

Cheers,
Tom- Hide quoted text -

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