PXIe-5672 + RFSG NIRFSG_ATTR_UPCONVERTER_GAIN + NIRFSG_ATTR_DIGITAL_EQUALIZATION

[serge_malo]

I was using the RFSG+FGEN drivers to create a RF signal at 2.3Ghz with 12.5Mhz of Bandwidth. When I looked at the spectrum, the power of the signal seemed it was not equalized (variation of +/- 1.5dB along the 12.5Mhz BW). So, I tried to use the "NIRFSG_ATTR_DIGITAL_EQUALIZATION_ENABLED" attribute, but this attribute is not available when the RFSG is initialized in "UpconverterOnly"
mode.

So, I decided to use RFSG only to create my RF signal, and enable the attribute "NIRFSG_ATTR_DIGITAL_EQUALIZATION_ENABLED".
I used niRFSG_InitWithOptions("RangeCheck=1,Cache=1,DriverSetup=AWG:AWG");
The signal on the spectrum was much better (Variation of +/- 0.5dB along the 12.5Mhz BW).

But now I have a new problem: I can't change the power of the signal during the

generation state. The function niRFSG_ConfigureRF returns the error "Operation failed because the signal generator is not in the Configuration state". I used to be able to change the attribute "NIRFSG_ATTR_UPCONVERTER_GAIN" during the generation when I used the "UpconverterOnly" mode.

My question is:
How can I use the attribute "NIRFSG_ATTR_DIGITAL_EQUALIZATION_ENABLED" AND be able to change the power while generating, on a PXIe-5672?

I'm using RFSG 1.4. Would it be possible on a newer version of RFSG?

[Doug_L._Bear]

The niRFSG-ConfigureRF which is a parent function of the Power Level function is only available in the configure state for the 5670/5671/5672.  However with the  5650/5651/5652/5673 it can be used in the configure or generation state.

This information is available in the niRFSG_ConfigureRF page in the NI RF Signal Generators Help.

[serge_malo]

Hi Doug,

Thanks for your answer.

This is a bit "sad". I mean, I used to be able to change the Power of the 5672 during the generation state, because I used to initialize the RFSG session with the option "DriverSetup=UpconverterOnly:1".

But now, since I need to be able to use the attribute  "NIRFSG_ATTR_DIGITAL_EQUALIZATION_ENABLED", I can't initialize the RFSG session with this option. So now, I lose the flexibility of being able to change the power "live".

I was wondering if there was a work-around for this. Something like enabling the equalizition through an option passed to the niRFSG_InitWithOptions function, along with the "DriverSetup=UpconverterOnly:1" option.

Or if this is really a limitation of the 5672 Hardware.

[Doug_L._Bear]

You were able to switch this in Upconverter only mode because there is no continuous generation in that mode.  You simply tune to the center frequency and set the power level and call it a day, its set.  If you change it you do that again, but there is no continuous running.

When you are using the 5672 in RFSG you are in a continuous generation state so these properties are not settable.

Essentially you are experiencing the same behaviour you were before.  In both situations this is only settable in a configuration state, the difference is in how you are generating the data.