Module 10.3 MSG/MAG and K Factor of Transistor
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Freq
(GHz)
MagS11
(Magnitude)
AngS11
(Phase Angle)
MagS21
(Magnitude)
AngS21
(Phase Angle)
MagS12
(Magnitude)
AngS12
(Phase Angle)
MagS22
(Magnitude)
AngS22
(Phase Angle)

Make a custom Sparameter.s2p file.
Step 1 : the Sparameter.s2p template file.
Step 2 : Open the Sparameter.s2p with a text editor.
Step 3 : Replace the value of the Freq., Mag., and Ang. with your device S parameters
Step 4 : Save the file and exit.
Step 5 : Browse and submit your new Sparameter.s2p file.

 


 
Introduction:

A convenient way of expressing the sufficient conditions for stability of the microwave amplifiers is stable factor (`K`) and `|Δ|`.
When `K` > 1 and `|Δ|` < 1 that the amplifier is unconditional stable.
The maximum transducer gain under simultaneous conjugate match in this condition is called maximum available gain (MAG).
On the contrary, when `K` < 1 and `|Δ|` < 1 , the amplifier is potential unstable.
The maximum stable gain (MSG) is defined as the value of maximum transducer gain when `K`=1.


`K` : Stable Factor

`G_(T,max)` : Maximum Available Gain(MAG)

`G_(MSG)` : Maximum Stable Gain(MSG)

     `K= (1- |S _11 |^2 - |S _22 |^2 + |∆ |^2 )/(2| S _12 S _21 | )`

`|∆| = |S_11 S_22 - S_12 S_21|`

`G_(T,max)` `= |S_21 |/|S_12 | (K- sqrt(K ^2 -1 ) )`

`G_(MSG)` `=` `(| S_21|)/(|S_12| )`