Thanks ACWWong,
I known the relations. That's why I speak the conflict!
One thing I forgot to point out. My filter is a complex one, which has 4 inputs( I+,I-,Q+ and Q-) and corresponding 4 outputs. While I setting the noise simulation eviroment. In the output cyclic field, I select voltage and select just one of 4 paths signal and let the minus one is gnd. In the input cyclic field, I do the same thing.
I wonder to know if the input reference noise is caculated to the only voltage I refered while the output noise is counted all of the 4 paths?
I want to use just one input port and split it into 4 paths signal(I/Q) and group the output four paths into one port to do noise analysis. But I don't known how to do it