RadiMation Application Note 141

How to create and apply a cable correction

This RadiMation^® application note explains how to create a cable correction and how to select it in RadiMation^®. Cable corrections can be used for several reasons:

• for cables in emission measurements
• when using attenuators in a conducted immunity calibration setup
• correcting a cable from a coupler to a powermeter in an immunity test.

By specifying the actual correction for the cable loss, RadiMation^® will be showing the correct measurement values.

The procedure to determine and select a cable correction, consist of 3 steps:

1. Create a calibration file.
2. Create a Cable device driver and apply the correction file.
3. Add the cable to the test equipment.

Create a calibration file

There are two methods to create a correction file:

Measure attenuation or gain

It is possible to use the attenuation gain measurement to automatically create a correction and measure the cable or attenuator with a signal generator and a power meter or spectrum analyser.
this is described here: Attenuation / Gain System Calibration

Create a correction manually

To create a correction file manually, create a new correction file:

    File

       New

          Correction

Click insert row to add a second row and set the start and stop frequency with the corresponding attenuation values.

And save the correction to a file

    File

       Save correction as...

It is also possible to paste data from for example Excel with the 5th button (paste data from clipboard). Make sure the data is in MHz and correction in dB. This feature is particularly used when correction values are supplied with a device or created with other software.

Create a cable device driver

    Devices

       Devices

          Cables

             Add Cables...

1. Choose configurable cable and click 'New'
2. Enter a description for the cable or attenuator
3. Below at Correction files select the applicable correction file.
4. Click "Ok" to close the window.

Add the cable to the test equipment

To apply the cable, open test equipment:

    Test-sites

       Configure

1. At the pull down menu select the applicable test equipment, or if needed create a new one.
2. Select the 5th tab called "Cables"
3. Click the button "Add" and add the cable to the applicable path.

The ability of an EUT to be immune to incoming electromagnetic interference. This is equivalent to the term susceptibility that is used by some standards.

Decibel