Does Yopt = Gopt + jBopt depend on Ls, Lg in cascode LNA?

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Osawa

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Here is a cascode LNA.
Does NFmin depend on Lg and Ls?
And does Yopt = Gopt + jBopt depend on Ls, Lg?

 

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Ls and Lg are used to make the input impedance closer/pull down/pull up to the Optimum Noise Impedance.( Zopt or Yopt)
Optimum Noise Impedance is independent from Lg and Ls and it's intrinsic parameter of the active device.When they are used, Zin will be Zopt to obtain NFmin.
 
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    Osawa

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Thanks. According to the application note, , Yopt is calculated as follows:



In this case, Gopt and Bopt depend on Gc, Gu, Rn, and Bc.

Yc = Gc + jBc also depends on input referred noise sources, Vn and In as shown in that page.

Vn and In, in turn, depend on Ls and Lg.

Therefore, Yopt will depend on Ls, Lg.

Please tell me where I am wrong.
All quantities I used are from the application note above.
 

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