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VSS Filed Based Mixer Issue

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User_from_the_Earth

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Hi all:

I have an issue trying to simulate a file based Mixer in VSS AWR simulation Software.

I have modeled the mixer using the file based model. I use the spur table provided by the manufacturer to give this information to VSS.

Ok, so the point is although it is working it doesn't work as it should:

We know that the output voltage of a mixer will be: (K/2)*V_1*V_2

Where K are the device losses and V_1 and V_2 are the LO and RF inputs.

Ok. So, if we use two inputs of 10dBm and -10dBm and we consider K=0 we should have an output of -40dbm.

(Output_voltage)^2 /2r = 20log(output_voltage) - 10log(100)=> -40dBm

Ok, nice. I don't have this level at the mixer output (and, of course, it is specified a 0dBc for this harmonic in the spur table). I have a -30dBm level.

On the other hand I don't really understand what is the "GCONV" parameter exactly. Is it the 20log(k/2) parameter directly? Is it only K? The MWO help doesn't say much about it.

One extra issue:

When I was making some modifications in order to be able to understand what is the issue and what is K exactly, I made some modifications and it reports a warning message:

"MIXER_F.A4 : Estimated signal gain is 0 because the 1,-1 product is not being generated. The MODE parameter may be incorrect for the input and LO center frequencies."

Ok, I guess that maybe it is failing due to the 0 losses parameter (K=0) I used in the probe. But it doesn't make much sense because it says that "The Mode parameter may be incorrect for the input and LO center freq"
BTW: f1=300Mhz f2=255Mhz fout=5Mhz MODE= diff.

I tried to solve it using other posts (BTW: nice books in one of the threads, thanks), MWO help and google in general, but I can't make it.


Thanks to all of you.
Best regards.

PS: In the real simulation I'm not using this GCONV=0 value. It is only to check how this VSS model works.
 

I don't want take this from the grave again, but I solved it:

GCONV is just the losses that the IF out will have from RF input if you have at OL port the input power that you said in the Local oscilator power option in the mixer model.

Regards.
 

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