load pull with ADS - RF Cafe Forums

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Noise
Post subject: load pull with ADS Posted: Wed May 02, 2007 9:50 am

Captain

Joined: Tue May 02, 2006 4:59 am
Posts: 15
Hello friends,

I have some problems regarding load pull simulation using ADS design guide.
I am using LDMOS with spice model .
Unfortunately i received error message (converges problem) for large input signal.
For small signal it runs OK.
Maybe the S11_rho and S11_center is not defined well ?
I am not sure I understand how to defined the sweep value for S11

Thanks

Top

Jeanalmira
Post subject: Posted: Fri Jul 06, 2007 5:28 am

General

Joined: Tue Mar 15, 2005 11:43 pm
Posts: 65
Location: Singapore
Hi there,

The converge problem commonly happens during large-signal simulation. What most likely to happen is the large-signal model parameters have limitations on high-power sweep, e.g such as breakdown voltage and so on.

The fast way to check is, you may lower the output power sweep, step by step, let's say by 1dBm and see whether the simulations sweep ok. Or, you may want to try to reduce the sweep power step to smaller steps.

I believe it's nothing wrong with your simulations, the problem lies in the model. So probably you may want to try to modify the model large-signal parameters.

I hope it helps.

Best Regards,
Jean

Posted 11/12/2012