ADS LSSP (Large Signal S Parameters) ERROR
I'm doing a diode, I want to analyze LSSP parameteres of the diode.
RF=24.125 GHz
LO= 23.125 GHz
IF=1GHz
As in ADS example I connect in series a P_1Tone, wich is port 1 and RF, and in series a V_1Tone, wich is LO. at the anodes diode.
At the catode's diode I connect Term port 2, and I name this point Vif.
I put Simulation Device LSSP. I configure it this way (as LSSP2 example in ADS)
Freq[1]=LO
Freq[2]=RF
order[1]=3
order[2]=3
LSSP_FreqAtPort[1]=RF
LSSP_FreqAtPort[2]=IF
I simulate and I get this message:
"No output was generated by the simulator"
"Port 1 has no power, spFreq at 2.4e10
Por 2 has no power,spFreq at 1e9"
What does it mean? I put power in in Vtone and Ptone.
Please, I really need help with this one. Thanks
Thanks
Maybe post fast a screenshot of your setup!
At the ADS Genesys not all spice models works. How I understood you are trying to get from spice some LSSP. IMHO it smell by extremely virtual staff.
In ADS some of the components or sources act as short circuit or in other words cannot be used as meant for, Check for such things in simulator model help in ADS. Generally these things are mentioned in note: section of ADS Help of that component,
And do post a pic of ur model that we may try to get clear understanding of the possible errors involved..!
Thank you to all.
I post here my schematic and the diode model (SPICE model of the manufacturer).
I've already correct some errors, in assigning frequencies. Now it gives an output. But it's not what I was specting. An still it gives the message: "Port 1 has no power, spFreq at 2.4e10
Por 2 has no power,spFreq at 1e9", it's this normal.
I'm trying to design a mixer, so I wanted to see the impedance the diode presents for different LO power. I don't know how to plot it, when plotting Port(Z1) it gives always 50Ohm without variation...
I can't see the error, or what i'm doing wrong. I've checked for info in ADS tutorial, but it was not too much help.
You have also to drive your second terminal with a source because you want to simulate LARGE signal s-parameter, you have to define your input power. Second error: in LSSP Setup, define correctly the order of frequency: in your case:FREQ[1]=RF, FREQ[1]=LO!
Thanks for the help (and sorry for the delay on answering). Unfortunately, I continue to have problems to understand LSSP from ADS. I understand what is for, but no how to configure it en the case of a diode mixer.
If 2 Source Ports are needed, one in RF for sure, but the other, in LO or IF?. In this case a mixer is a downconverter. I don't undertand how Freq in LSSP should be asigned, and neither the orders... I don't find a clear explanation in ADS help or other place by the moment, I'm still looking
I went back reading ADS Help. In C:\ADS2008\doc\cktsimlssp\ads2008\Performing_a_Lar ge-Signal_S-Parameter_Simulation.html.
" Apply ports to all inputs and outputs. Use a P_1Tone or P_nTone power source to drive a port. Terminate other ports using port-impedance terminations (Term). Verify impedance.
The power level at a passive port (Term) will be calculated by turning on power sources and measuring the power at the port; this value will be used to drive the port.
?In circuits with mixers, use a voltage source for the LO, not a power source. This prevents the LO input from being recognized as a port and consequently having the S-parameters calculated with respect to it
"
So in my case a Mixer downcoverter, only a P1_Tone is a port in RF, LO is a voltage Source and a Term is IF. So I wouldn't need to have 2 source ports.
I don't understand how to assign frequencies, orders, etc.
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