dog1
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well, I think that I don't need to change the matrix.
let's say, the two port is a mosfet, and its ABCD is thus given by the character of the mosfet. whatever you do at the load or source shouldn't change the ABCD of it. because when you calculate the ABCD, the condition is the output is either shorted or opened.
Of course, you can include the resistor into the two port, so that the two port is now a mosfet with an resistor at the drain. And then again you can calculate the output noise voltage and current source of the new two port due to the resistor and put it at the end of the two port, and then shift it back to the input using the ABCD of the new two port. but that's not what I am talking about.
the way I am following is to keep the initial two port unchanged after adding the resistor, and the resistor will just be seen as a load. And my analysis follows in the way I mentioned before.
Obviously there is something wrong with that analysis, but I cannot figure out why.
Attached is the way mentioned in the book about how you can shift the noise source from the output back to the input. I think it should hold regardless of the load or source condition and only related to the ABCD of the two port itself.
Thanks!
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