How to add a reference network in a circuit in ADS?

I am designing LNA and want to put a BPF in front of it. LNA is designed already. Now designing BPF, so I would like to put LNA circuit as reference network with BPF. So, How I can do it in ADS? Anyone can give me any suggestions, any help, any comment? Please reply ASAP.

If I understand your intent correctly, simply make two circuits on your schematic. The first circuit will have the LNA all by itself (with a proper signal source and load connected). Circuit two would be a copy-paste of the LNA circuit with your bandpass filter connected, then terminated into a proper load. Set up net names like LNA_Vout and Filtered_LNA_Vout, or whatever makes sense. Then plot those two traces on the same set of axes to get a side-by-side comparison of performance.

You are just making the simulator run both sets of circuits at the same time, even though they are not connected to each other.

In ADS, you can put some labels, then You can write some equations to compare among these labels.