How to simulate the NF of multiports of block?

[microwaver]

As the subject point out, How to simulate the NF of multiports of block? when simulate the NF need first define a input port/voltage/current as noise source,then you get the deteriorateion of SNR for the block.that's ok for differential input block.but how to get for a four phase input such as charge pump ,polyphase filter etc
Can experts give me some advice?

 

[RF-OM]

I am not sure I understood your question right, but if you need to count several noise sources simultaneously connected to the system input there are one proven way to do it. You need to replace all sources but one with its equivalent resistor, usually 50 Ohm for the most of RF systems. Then calculate the effect from the noise source that still connected to the system. After this leave another noise source on and replace all others with resistors. Repeat this as many times as it necessary. You will finally get the effects from each of the noise sources. Then take the superposition and you get the total noise performance for your system. If this is what you were asking and you need more detailed information I may check my books and copy a few pages for you.

 

[kspalla]

in ADS nf(2) is used for NF calculation.
In general nF where n is the port to find the NF.

 

[Abhishekabs]

Do you know why there is option nF(1) along with
nF(2) ? what is the use of this function nF(1)?
Both have different outputs.

 

[kspalla]

Dear Abhi,
Just like S11 and S22, there is NF calculation accounting the noise contribution at all ports.
nf(1) is the NF due to port 2 and so on.
nf(2) is NF at port 2 due to all ports.

If you still need clarification let me know.