VNA SetUp Mode 'unknown' not supported / CompareParameterMatrices not working

[Sebastian Neusch]

Hi, 

I try to get e.g. the b1_p1 measurement to work. But (with an self written driver for the HP8720A). Always get the error "Error: VNA SetUp Mode unknown not supported."
This is thrown from 
 public void y(VnaSetUpMode mode)
 {
     System.Console.Out.WriteLine(mode.ToString());
     int oldAverage = supports_splid4 ? IFAverageFactor : 0;
     switch (mode)
     {
         case VnaSetUpMode.unknown:
             throw new System.Exception("VNA SetUp Mode unknown not supported.");

So it looked initially like an driver issue. But somehow the functions CompareParameterMatrices seems to not work because if I call:

VnaParameter[,] test = new VnaParameter[1, 1] { { VnaParameter.Receiver(VnaReceiverType.b, 1, 1) } };
VnaHelper.GetVnaSetUpMode(test);

The return value should be VnaSetUpMode.b1_p1;

As this if condition supposes:
 if (VnaParameter.CompareParameterMatrices(parameterMatrix, new VnaParameter[1, 1] { { VnaParameter.Receiver(VnaReceiverType.b, 1, 1) } }))
 {
     return VnaSetUpMode.b1_p1;
 }

But it is VnaSetUpMode.unknown.

What am I missing ? 

Kind regards

Sebastian

[Michael Wollensack METAS]

Hi,

see the following IronPython script. You can run it inside VNA Tools:

import clr
clr.AddReference('System.Windows.Forms')
clr.AddReference('Metas.Instr.Driver')
clr.AddReference('Metas.Vna.Data')
clr.AddReference('Metas.Vna.Tools')
from System.Threading import Thread
from System.Windows.Forms import MessageBox
from Metas.Instr.Driver.Vna import VnaHelper
from Metas.Vna.Data import VnaParameter
from Metas.Vna.Tools import Script

s = Script(RootPath)

m = VnaParameter.ParameterMatrixFromString('b1_p1')

mode = VnaHelper.GetVnaSetUpMode(m)

print(mode)

This returns 'b1_p1'.

Regards

Michael

[Sebastian Neusch]

Hi,

that is true, I have to correct myself: it is two parameters. See the attached Screenshot. To set up Test and Reference Receivers Port 1 it actually sets up [0, 0] = b1_p1 and [1, 0] = a1_p1.

This would be: m = VnaParameter.ParameterMatrixFromString('a1_p1;b1_p1') in your script, which results in "unknown" too.

Kind regards,

Sebastian

[Sebastian Neusch]

Addition: 

Power Sensor Measurement I would like to setup "P1" which results in "s11;b1_p1".

[Michael Wollensack METAS]

Hi,

that's not supported by the  VnaHelper.GetVnaSetUpMode method. This method is used in the legacy drivers where I want to mainly measure S-parameters and Switch Terms.

You need to implement the ParameterMatrix property. Take a look at the AgilentPna driver for example.

For a power sensor measurement you need "s11;a1_p1".

Regards

Michael

[Sebastian Neusch]

Hi,

do I understand right, that the two parameters should be measured cohearent so cohearant measurement of s11 & a_p1 ? Or could it be sequentialized. ? 

Kind regards,

Sebastian

[Michael Wollensack METAS]

Those two parameters should be measured at the same time.