a question in ADS optimization.

[triple_core]

Hi,

I want optimize my circuit, so that it has a flat gain in the whole frequency.

In the optimization goal, I can only write e.g. max. of dB(S(2,1))=14, min. of dB(S(2,1))=12, and so on.

In fact, the value of gain is not important for me, I only want to have a flat gain. If I write the upper expression, the simulator does not accept the results such as max=12.5, min=11. But the results is better for my application.

Anyone has idea, how to write the goal expression in this case?

Thanks a lot!!

 

[si14]

Your design should has the ability to achieve these values. Try lower gains, step by step increase your gain. In each level you will probably get better results. If you are getting for example 5dB, you can not converge your optimization with one run.
Hope that helped.

 

[kspalla]

Check the gain slope over the band and decide any gain compensation is required or not.
If the gain slope is too much then you can not get flat gain over the band.

 

[RealAEL]

ADS has a ripple measurement that simply returns the deviation from the average of a measurement.

In the schemantic add a measurement expression like:

a=ripple(dB(S21)) or a=ripple(mag(S21))

and the optimize for a=0

 

[triple_core]

thanks RealAEL, that's what I really want to know.

 

[erno]

Hi,

You can also set the minimum and maximum gains to be the same i.e. 13 dB ...

Regards

Erno

 

[sohkha]

Hi guys,
I have a problem in ADS optimization. I want to know how to write a goal in case of equiripple in whole pass band. Let say i want my S11 to be at -10dB and i have five transmission poles in pass band.

thanks