Characterize and Analyze Drift

[VNA Tools]

Hi,

How do I characterize and analyze drift?

Regards

Michael

[Michael Wollensack METAS]

Hi,

Characterize Drift:

see https://groups.google.com/d/msg/vnatools/BtX97T2K-98/elcDeaVHn8EJ

Analyze Drift:

Let's assume you have measured a trough connection for 24h. And you've error corrected the data. Then you can use the attached script to generate the drift table which is used in the Database / VNA Device / Drift.

How to use this script:

1. Copy the script to 'C:\Users\Public\Documents\Metas.Vna.Tools\Matlab'
2. Start MATLAB
3. Define a variable which specifies the data directory, e.g.: datadir = 'VNA123_Test\VNA123_Drift_01\SOLT_01_out\Drift'
4. Run t = AnalyzeDrift(datadir)
5. This script generates a text file which contains the wanted table, see resfile = [datadir '\' 'AnalyzeDriftResult.txt']
6. Copy the content from the text file and paste in to the Drift table of your VNA device (VNA Tools / Database).

Hope this helps.

Regards

Michael

[George Krikelas]

Hello Michael.

Sorry for opening the subject again but I have been struggling with this for days without result. The only thing I have managed so far is to get to the point where I get the following error: 

>> t=AnalyzeDrift(datadir)

24h_drift_0001.sdatb

Metas = 

    Vna: [1x1 struct]

Loading .NET Assembly: C:\Program Files (x86)\METAS\Metas.Vna.Tools\Metas.UncLib.Core.dll

Loading .NET Assembly: C:\Program Files (x86)\METAS\Metas.Vna.Tools\Metas.UncLib.LinProp.dll

Loading .NET Assembly: C:\Program Files (x86)\METAS\Metas.Vna.Tools\Metas.UncLib.Optimization.dll

Loading .NET Assembly: C:\Program Files (x86)\METAS\Metas.Vna.Tools\Metas.Vna.AgilentModel.dll

Loading .NET Assembly: C:\Program Files (x86)\METAS\Metas.Vna.Tools\Metas.Vna.AgilentUncCalc.dll

Loading .NET Assembly: C:\Program Files (x86)\METAS\Metas.Vna.Tools\Metas.Vna.Calibration.Config.dll

Loading .NET Assembly: C:\Program Files (x86)\METAS\Metas.Vna.Tools\Metas.Vna.Calibration.dll

Loading .NET Assembly: C:\Program Files (x86)\METAS\Metas.Vna.Tools\Metas.Vna.Data.dll

Loading .NET Assembly: C:\Program Files (x86)\METAS\Metas.Vna.Tools\Metas.Vna.Data.Explorer.exe

Loading .NET Assembly: C:\Program Files (x86)\METAS\Metas.Vna.Tools\Metas.Vna.Database.dll

Loading .NET Assembly: C:\Program Files (x86)\METAS\Metas.Vna.Tools\Metas.Vna.Journal.dll

Loading .NET Assembly: C:\Program Files (x86)\METAS\Metas.Vna.Tools\Metas.Vna.Misc.dll

Loading .NET Assembly: C:\Program Files (x86)\METAS\Metas.Vna.Tools\Metas.Vna.Optimization.dll

Loading .NET Assembly: C:\Program Files (x86)\METAS\Metas.Vna.Tools\Metas.Vna.Tools.exe

Loading .NET Assembly: C:\Program Files (x86)\METAS\Metas.Vna.Tools\Metas.Instr.VisaExtensions.dll

Loading .NET Assembly: C:\Program Files (x86)\METAS\Metas.Vna.Tools\Metas.Instr.Driver.dll

Reference to non-existent field 'Instr'.

Error in LoadVNATools (line 47)

    d2 = [char(Metas.Instr.Driver.Tools.DriverFolder) '\'];

Error in LoadSParamDataAsStruct (line 5)

LoadVNATools();

Error in AnalyzeDrift (line 17)

    data{i} = LoadSParamDataAsStruct([datadir '\' d(i).name]);

When I try to run "ExampleSParamData.m" (after restarting Matlab and not doing anything else), I get exactly the same error.

I use Matlab R2015b, VNA Tools 1.9, UncLib 1.9.

Do you have any idea what the problem might be?

Regards,

George

[Michael Wollensack METAS]

Hi,

it looks like the Matlab wrapper for VNA Tools is not able to load the VNA drivers. In most cases they are not needed. So could please try to comment out the follwoing lines in the LoadVNATools.m file:

    %LoadAssembly([d 'Metas.Instr.VisaExtensions.dll']);

    %LoadAssembly([d 'Metas.Instr.Driver.dll']);

    %d2 = [char(Metas.Instr.Driver.Tools.DriverFolder) '\'];

    % Load all drivers

    %d3 = dir([d2 'Metas.Instr.Driver.*.dll']);

    %for i = 1:length(d3)

    %  LoadAssembly([d2 d3(i).name]);

    %end

[George Krikelas]

Thanks for the reply.

I commented out the indicated lines, now I get: 

Reference to non-existent field 'Database'.

Error in LoadVNATools (line 57)

dbl = Metas.Vna.Database.DatabasePath.LookUpTable(Metas.Vna.Tools.Global.DatabaseRootPath);

Error in LoadSParamDataAsStruct (line 5)

LoadVNATools();

Error in ExampleSParamData (line 4)

d = LoadSParamDataAsStruct([pwd '\' 'Example_01.sdatb']);

[Michael Wollensack METAS]

Ok,

try to uncomment again the frist two lines:

    LoadAssembly([d 'Metas.Instr.VisaExtensions.dll']);

    LoadAssembly([d 'Metas.Instr.Driver.dll']);

    %d2 = [char(Metas.Instr.Driver.Tools.DriverFolder) '\'];

    % Load all drivers

    %d3 = dir([d2 'Metas.Instr.Driver.*.dll']);

    %for i = 1:length(d3)

    %  LoadAssembly([d2 d3(i).name]);

    %end

Regards

Michael

[George Krikelas]

Well, I get the same error again. I think the problem lies elsewhere. But I don't want to use up any more of your time, since this is not something you can answer easily. 

Thanks again,

George

[Mr Skinner]

Hi, I am also experiencing these same Matlab errors, and am wondering if a solution has been found.

Cheers

James

[Michael Wollensack METAS]

Make sure that your run LoadVNATools.m before creating the first uncertainty number with e.g.: LinProp.

Otherwise you've to restart MATLAB.

[Luca Oberto]

Hi,

is there a version of the AnalyzeDrift script that can be run within the scripting environment of VNATools (or in python outside VNATools) for who does not have a matlab licence?

Thanks,

Luca

[Gilberto Basso]

Hi, Years ago I wrote a long script that handled drift analysis according to the AnalizerDrift.m code and also according to the EURAMET code. I'm happy to share this script and hope it helps!

Please find Annex any notes for drift acquisition and the script. I checked various measurements with MathLab and everything seemed fine, but if someone on the forum or Wollensack himself could check it out, that would be great. See if it helps.

and sorry for my bad English

Gilberto Basso