Large signal measurement in ADS

[bkd]

Hi guy
Do anyone know how to measure large signal of bipolar transistor using ADS. I design oscillator, and try to analyse this one. THat why I need to use large signal parameter in caculation startup condition for oscillator.

 

[jayce3390]

Large signal S parameters ?

 

[haitaoz]

i think you are talking about it in time domain,right?

 

[khouly]

the large signal could be done using harmonic balance engine in ADS ,
the large signal s paramters simulation is a HB depenent

khouly

 

[bkd]

Thank, I can use Simulation_LSSP to have these large signal s parameter

 

[cooleyn]

HB solver is suitable for large signal oscillator simulation in ADS.

 

[bkd]

Using HP solver, you guy just have the final result for oscillation. We just use HB running, tuning until it have the oscillation output.
The problem is that we must analyse the circuit to get the starup condition and stable condition. What i want is that I can use Z matrix or Y matix method to design. After measuring large signal Z matix and Y matrix. and apply
-real(Zout)>real(Zloat)
Img(Zout)=-img(Zload)
at the operating frequency.
And then connect the circut, put the HB solver, and we have the running oscillator without any tunning. But till now I can not do this. I do not know at which RF drive power I can put in the P1_tone. I read in some book that this is -15 dBm. I try this one but this not run in HB as the oscillation condition satified. Some material use 10 dBm RF drive but the result from equation( to calculate Zout) is different from what measuring.
So does anyone have experience in large signal oscillator design.
I use the book The design of Modern Microwave oscillator for Wireless Application