Power Sensor calibration

[wickli...@gmail.com]

Hello Community

I do have two questions regarding power sensor calibration:

1. Is there some sort of documentation? or can anyone tell me the basic idea on how to do the measurements?

I assume I have to do a power calibration with a reference sensor and after that I measure the DUT, right?

Is it possible to measure flatness and linearity? If so, how exactly would I do that?

2. I seem to have a problem connecting to my R&S NRP-Z51 and Z-21.

I have no problems using the sensors with the R&S software, aswell as LabView and direct VISA communication (tested with the IDN command). Does anyone have the same problem?

Thanks in Advance

Patric

[Michael Wollensack METAS]

Hi,

> 1. Is there some sort of documentation? or can anyone tell me the basic idea on how to do the measurements?

Take a look at 10_Power_Example_1.85mm(f-m).

> I assume I have to do a power calibration with a reference sensor and after that I measure the DUT, right?

Yes

> 2. I seem to have a problem connecting to my R&S NRP-Z51 and Z-21.

The are several problems here:

- Older R&S NRP-Z sensor didn't implemented the USBTMC class. So you could use them either with R&S VISA or NI VISA and the NRP-NI-VISA Passport, see https://www.rohde-schwarz.com/ch-en/faq/r-s-nrp-z-sensor-is-not-available-in-ni-visa-faq_78704-999873.html. I guess you use the second option.

- But there is still another problem.  The IVI.VISA GlobalResourcManager.Open method is not calling the constructor of the NRP-NI-VISA Passport, because the case with resource names starting with RSNRP:: is not implemented by the IVI foundation. And I want to use the IVI.VISA interface that I'm able to run VNA Tools either with NI VISA, R&S VISA or Keysight IO Lib.

Details (the comment lines are not working):

            var d1 = Ivi.Visa.GlobalResourceManager.Open("GPIB0::16::INSTR") as Ivi.Visa.IMessageBasedSession;

            d1.RawIO.Write("*IDN?");

            var s1 = d1.RawIO.ReadString();

            d1.Dispose();

 

            //var d2 = Ivi.Visa.GlobalResourceManager.Open("RSNRP::0x0021::101433::INSTR", AccessModes.ExclusiveLock, 1000) as Ivi.Visa.IMessageBasedSession;

 

            //var rm2 = new NationalInstruments.Visa.ResourceManager();

            //var d2 = rm2.Open("RSNRP::0x0021::101433::INSTR", AccessModes.ExclusiveLock, 1000) as Ivi.Visa.IMessageBasedSession;

 

            NationalInstruments.VisaNS.MessageBasedSession d2 = new NationalInstruments.VisaNS.MessageBasedSession("RSNRP::0x0021::101433::INSTR");

            d2.Write("*IDN?");

            var s2 = d2.ReadString();

            d2.Dispose();

- I don't want to add a reference to NationalInstruments.VisaNS in VNA Tools, just to Ivi.Visa. Therefor I don't support NRP sensors connect directly to the PC over USB. I only support them using a NRP2 or NRX base unit.

Regards

Michael

[wickli...@gmail.com]

Dear Micheal

As always, thank you very much for your time and help.

If I understand you correctly, the easiest and probably only solution would be to work with a Power Meter wich works as a proxy between my computer and the power sensor. 

When I find time, I will investigate this approach. Thank you very much!

Regards

Patric