IIP3 setup in Harmonic Balance simulation in cadence

[fateme m]

Hi,
I have an LNA with this schematic:

and I inserted 2 frequencies to the input port and plotted the available gain with SP simulation:

then based on the curve for gain, I changed the two freq to 3.1GHz and 3.2GHz:

and then I had these set up for plotting IP3:


My question is why is it that when i change the ep point my IIP3 changes?? or based on what i need to choose my 1st and 3rd harmonics or the tones I inserted in the input port??? I chose them based on the gain curve.. is it wrong? and I chose the same frequencies that I chose for my input port as my 1st and 3rd harmonics...again there is a problem right??
please help I don't understand:???:

 

[pancho_hideboo]

and I inserted 2 frequencies to the input port and plotted the available gain with SP simulation:

Two frequencies have no meaning for SP Analysis.

My question is
why is it that when i change the ep point my IIP3 changes??

I can not understand what you want to mean at all.
Describe correctly.

or based on what i need to choose my 1st and 3rd harmonics or the tones I inserted in the input port???

I can not understand what you want to mean at all.
Describe correctly.

I chose them based on the gain curve.. is it wrong?

I can not understand what you want to mean at all.
Describe correctly.

and I chose the same frequencies that I chose for my input port as my 1st and 3rd harmonics...
again there is a problem right??

I can not understand what you want to mean at all.
Describe correctly.

Simply, your setting for "3rd Order Harmonic" is wrong.

frf1=3.1GHz, frf2=3.2GHz
fimL=2*frf1-frf2=3.0GHz
fimU=2*frf2-frf1=3.3GHz

1st Order Harmonic has to be 3.1GHz or 3.2GHz.
3rd Order Harmonic has to be 3.0GHz or 3.3GHz.