Help need for Noise Figure Equation Derivation of LNA

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narayani

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In " Microwave Engineering" by David M.POZAR. He has given directly Noise Figure Equation derivation as follows



How it has come Fmin , RN,GS, YS,and YOPT, he has showed some references. From those references he has written directly noise figure equation of LNA.
Can you somebody help me, How to get elaborate equation of Fmin, RN, YS,and YOPTGS.
If there is any related documents, how to derive elaborately above discussed parameters. Can you show me related documents of deriving NF.
 

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These parameters are generally defined by measurements for discrete components or extracted from an accurate model for integrated active devices.
Calculation of these parameters from an accurate model is easily done by aid of simulator.Hand calculation is very hard and will be erroneous.
 
BigBoss said:
Calculation of these parameters from an accurate model is easily done by aid of simulator.Hand calculation is very hard and will be erroneous.
Click to expand...
I don't want numerical calculations of the posting #1 parameters. From the equivalent circuits of FET or JFET or MOSFET's, how they have obtained equations of the parameters Fmin, Rn, Gs, Ys, and Yopt.
How we can obtain the elaborate equations of Fmin, Rn, Gs, Ys, and Yopt using equivalent circuit of FET.
Is there any related document or related software to obtain the equations for above mentioned parameters, can you show me.
I have shown the screen shot of FET equivalent circuit.
 

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I told you before...
You cannot obtain those parameters from this small signal equivalent circuit because it doesn't cover "Noise Contribution Elements" in the small signal model.Noise elements an be found in more complex models and there are two ways to obtain these values..
-Measurements
-Simulations
 
BigBoss said:
Noise elements an be found in more complex models and there are two ways to obtain these values..
-Measurements
-Simulations
Click to expand...
How we can obtain noise parameters using Measurements and Simulations, which simulator do we need to use. I am specific about equations of parameters such as Fmin, Rn, Gs, Ys, and Yopt using noise equivalent circuit model.

Below I have shown the screen shot of noise equivalent circuit.
 

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  • Noise_Equivalent_Model.jpg
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Any kind of RF simulator suh as ADS, SpectreRF etc. can find the desired parameters from an accurate model.
 
BigBoss said:
Any kind of RF simulator suh as ADS, SpectreRF etc. can find the desired parameters from an accurate model.
Click to expand...

As we know, using Agilent ADS, we can find noise figure of LNA nf(2). Is it possible to obtain equation of NF such as Fmin, Rn, Gs, Ys, and Yopt using Agilent ADS. If so, how we obtain equation of Fmin, Rn, Gs, Ys, and Yopt of NF posting # 5 noise equivalent model. Can you tell. Where we have to feed the noise equivalent model in Agilent ADS and how we can obtain, can you explain.
 

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