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Create De-Embedding Array RFSA

I keep getting a null array each attempt to Get De-embedding Array RFSA vi.  I setup the center freq, both sig-gen and sig-an, initiate the setting but still a null array.  I'm using the RFSA and RFSG toolkit with PXIe 5830.  I've uploaded LV2019 vi, where you need the RFSA and RFSG toolkit installed else missing VIs. 

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Message 1 of 13
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I'm told the PXIe-5830/20 does not support the de-embedding functions.  I looked at the Release Notes for  RFSA and the 5840 supports de-embedding as of version 18.2 RFSA. Nothing else is mentioned regarding de-embedding and the latest RFSA version Notes (ver 21.0.1) aren't yet posted on NI website.

Can someone confirm that the 5830 or 5820 does not support de-embedding?

 

richjoh_0-1633634256970.png

 

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Message 2 of 13
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Well, turns out the PXIe-5830 supports de-embedding using the RFmx Class though and NOT RFSA Class.  RFmx version 19.1 names it AttenuationTable where you can save to a s2p file.  Take a look at the manual here, https://zone.ni.com/reference/en-XX/help/374264N-01/rfmxinstrdotnet/html/allmembers_t_nationalinstru...  .  Search for "AttenuationTable" or "S parameter" and the same RFSA de-embedding function supported for PXIe-5830 are listed.  

 

So it just took a little research to answer my own question.  Now I'll go dig for those RFmx function I've been looking and got distracted by the RFSA de-embedding tools.  Can I Kudo myself? :^()

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Message 3 of 13
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What I said above is not all correct. RFSA class for PXIe-5830 De-embedding is supported. The only way to get S-parameter is to use RFSA.  RFmxINSTR supports saving or reading (not creating) an s2p file.  In the pic below, 5830 is listed as supported.

 

richjoh_0-1633840024871.png

 

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Message 4 of 13
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If you're trying to create an S2P file for use in de-embedding later on, I don't think it is capable of. Moreover, to create an SnP file, you would need a VNA and not a VST.

 

VNA will have the couplers at the ports to measure the full S parameter.

 

Looking at the help document, it only discusses the driver support to use an S2P file to apply de-embedding on the VSG/VSA but not create using them.

santo_13_0-1633840748772.png

 

-Santhosh
Semiconductor Validation & Production Test
Soliton Technologies
NI CLD, CTD
LabVIEW + TestStand + TestStand Semiconductor Module (2013 - 2020)
NI STS for Mixed signal and RF
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Message 5 of 13
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the pxie-5830 looks like a VNA from the description.  The RFmxInstr drivers allow use of a Attenuation Correction file but I did not see RFmxInstr VI to generate a Attenuation (scalar) correction file.  I assume the generation can be done using a sweep, measure IQ and convert to amplitude.  

 

richjoh_0-1634051391323.png

 

The RFSA function provides a de-embedding (create or generate) VI which list the PXIe-5830 as supported hardware.  I could not get this to work.  Checked the NI Examples and no examples existed.  Since the pxie-5830 is a VNA I'd expect it to give ampl & phase, de-embedding data when using the RFSA VIs.

 

richjoh_0-1634052031754.png

 

 

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Message 6 of 13
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Technically it is still not a VNA. https://www.ni.com/en-us/shop/hardware/products/pxi-vector-network-analyzer.html

PXIe-S5090 is the only available VNA listed on NI site.

VNA contains reference couplers at both the ports, allowing them to measure S11 or S22 parameters and they are capable of generating/acquiring signal on either of the ports.

 

In a VST case, it lacks the coupler. My understanding of the RFSA function is that it can support de-embedding if you pass it an S2P file but not create an S2P file somehow.

-Santhosh
Semiconductor Validation & Production Test
Soliton Technologies
NI CLD, CTD
LabVIEW + TestStand + TestStand Semiconductor Module (2013 - 2020)
NI STS for Mixed signal and RF
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Message 7 of 13
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Thanks for the tip, it makes total sense because the PXIe-5830 doesn't have the reference couplers as you mentioned in your reply.  This would explain why I could not proceed when I set the S-parameter orientation to Vector. Scalar orientation was excepted though. 

 

This question persist, is the "Create De-embedding S-Parameter Table.vi" RFSA supported by the PXIe-5830?  As I look at the Help, the 5830 is listed as a supported hardware.

richjoh_0-1634057616482.png

 

If the Create De-embedding works using Scalar data, I could read the values back into the RFmxInstr SigGen and SigAnalyzer drivers.

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Message 8 of 13
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I keep posting the wrong snippet picture, here's the pic I meant to post.  The VI should spit out S-parameters (scalars only) if it supported by the PXIe-5830.  I tried various settings of RFSA and RFSG to no avail.  The initial Labview code is posted at the top of the thread.

 

richjoh_0-1634062738127.png

 

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Message 9 of 13
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Yes, based on the description it can create a table from the provided S2P file.

 

But not generate it on its own.

 

S2P file -> De-embedding table (RFSA) -> Signal Analysis

 

Without the S2P file, it CANNOT create the de-embedding table

 

-Santhosh
Semiconductor Validation & Production Test
Soliton Technologies
NI CLD, CTD
LabVIEW + TestStand + TestStand Semiconductor Module (2013 - 2020)
NI STS for Mixed signal and RF
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Message 10 of 13
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