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Transfer Function: Magnitude and Phase of Complex Function

  • Thread starter mvpshaq32
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Homework Statement



f(s) = f([itex]\sigma[/itex] + j[itex]\omega[/itex]) = [itex]\frac{1}{(1+s)^2}[/itex]

Find the magnitude and phase angle of f(j[itex]\omega[/itex])

Homework Equations



s = j[itex]\omega[/itex] is a substitution you can make, but I'm not sure if you are supposed to apply that here

The Attempt at a Solution



I tried substituting [itex]\sigma[/itex] + j[itex]\omega[/itex] into the function and applying s = j[itex]\omega[/itex].

Then I get

[itex]\frac{1}{(\sigma + 1)^2 + 2s(\sigma + 1) + s^2}[/itex]

I have a feeling it's supposed to be a quadratic pole, but the form of this doesn't match the form of a quadratic pole exactly.
 

Answers and Replies

  • #2
rude man
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If they ask for f(jw) and they give you f(σ + jw) then σ = 0. So yes, let s = jw and proceed.
 

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