How to compute values for T network in the power amplifier?

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Osawa_Odessa

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Hi,
I am learning about RF power amplifier from a paper "Design of 2.1GHz RF CMOS PowerAmplifierfor 3G". I want to simulate it in Cadence but there are no specific values for components. Now I am wanting to compute value of components and power gain.
The picture is an RF power amplifier class AB with two stages.
C1, C2, and L1 is an input matching network. The voltage source has resistance Rs = 50Ω. I want to compute values of C1, C2, and L1 but I got stuck.
Could you guide me on this? Thanks.
 

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You need to know M1 input impedance for the given operation point and circuit. Unfortunately, it's affected by M1 load impedance. So you'll usually start with an estimated value and later adjust the matching networks.

Then the matching network can be designed by different methods. Graphical design in Smith Chart is a common method, there are also software tools helping you with the calculation.
 
Thank you, FvM.
I intend to model GS of the MOSFET by a capacitor Cgs and a resistor R in series with it. However, I don't know how can we know the values of Vgs and R at a specific frequency. Is there any reference for choosing these parameters?
 

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