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PNA-X Opt087 Swept IMD with Different Power Levels

Question asked by andyTPE on Nov 17, 2010
Latest reply on Nov 22, 2010 by daras
I have a PNA-X equipped with Opt 087 running fware 09.22.02.

To date I have been getting good swept IMD results with 087 and a segmented frequency sweep. 

I now have a device that is a high linearity broadband device, whose IP3 falls off over frequency.  Ideally I would like to be able to change the tone power as a function of frequency - specifically I want to reduce the drive level with increasing frequency.  Fware 09.22.02 does not support this capability.  So, a couple of questions:

Do any newer releases of firmware support this feature?

If not, has anyone run up against this issue before and what solutions have you investigated?  My options right now appear to be:
* Split the frequency sweep into multiple channels and operate each channel at the power level required for that band.
* Try and fool the PNA-X by using a 'bogus' offset table when performing the source power calibration.  Or, alternatively, uploading the source power calibration terms (for both Src1 and Src2), adding an frequency dependent offset which represents my desired delta's and then downloading back to the instrument.  I appreciate that I would have to manage the source attenuators i.e. I do not want to demand a power level that is outside the range of the source and would necessitate a source attenuator change (thereby invalidating the 2 port cal).

All thoughts and feedback gratefully received,