how to simulate active polyphase filter frequency response by spectre in ac simulatio

[steven_jun]

Dear

i dont know how to simulate active polyphase filter frequency response by spectre at ac simulation

i add the simulus as follow : V1 Iin+ 0 1V ac 200m 0
V2 Iin- 0 1V ac 200m 180
V3 Qin+ 0 1V ac 200m 90
V4 Qin- 0 1V ac 200m 270

question is how to plot output frequency response curve?

thanks

 

[pancho_hideboo]

plot following.

( v("/Iout+", ?result "ac")-v("/Iout-", ?result "ac")) + complex(0,1)*(v("/Qout+", ?result "ac")-v("/Qout-", ?result "ac") )

Here you do frequency sweep from minus frequency to plus frequency.

But you can get minsu frequency response from plus frequency response since "I(-freq)=conj(I(freq))" and "Q(-freq)=conj(Q(freq))" are satisfied.
So you don't have to do frequency sweep of minus frequency.

 

[steven_jun]

thank pancho_hideboo

i try it,but the function complex dont support and i cant not find it in the calulator
the message is *Error* ("complex" 3 t nil ("*Error* complex: argument #1 should be a number (type template = \"n\")" drwave:92266632))

 

[pancho_hideboo]

Sorry.

I updated an equation for plotting.