Conducted immunity fixed voltage algorithm

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Algorithm[edit]

The following steps are taken in the Conducted Immunity Fixed Voltage test:

  1. Initialize all the equipment that should be used
  2. Set the carrier frequency to the first frequency
  3. Determine the Voltage level that should be levelled:
    • Fixed voltage test level
    • Variable voltage test level: Retrieve value from specified correction file
  4. Determine the maximum accepted voltage test level:
    • Maximum accepted voltage test level = 10 ^(20 * Log10(VoltageTestLevel) + Tolerance) / 20
  5. Set the signal generator to the lowest carrier level
  6. Regulate the power level to the new power level, while regulating to the power level, monitor the injected current, and stop regulating if the specified current level is reached.
  7. Measure the voltage input. Depending on the configured 'Voltage measuring device':
    • Multimeter
      1. Read out the multimeter for the measured voltage
    • Oscilloscope
      1. Retrieve a measurement of the oscilloscope
        1. Quadrate all the values of the measurement, and add them to eachother to a total
        2. Divide the total by the number of points in the measurement
        3. Take the square root of the divided total.
    • Sensor power meter
      1. Retrieve the power measured at the powermeter (optionally corrected by the correction file, that is attached to the used powermeter)
        1. Convert the measured power to Watt
        2. Multiply the value in Watt by 50 Ω, and take the square root
    • Spectrum analyser
      1. Select the peak detector
        1. Select Auto RBW and Auto VBW
        2. Select Zero span, on the tested carrier frequency
        3. Take sweep with the spectrum analyser
        4. Determine the maximum measured dBuV level during the sweep
        5. Correct the maximum value with the value that is specified in the correction file that is attached to the used spectrum analyser. (the correction file should have a 'frequency' and 'correction' column)
        6. Convert the value to Volts
  8. If the power is out of the accepted range (step 3. and 4.), and the current is below the specified current limit, adjust the signal generator level and continue at step 6.
  9. Calculate if the power level should be changed to apply 'modulation conservation'
  10. Measure the AD channels for the 'Before' measurement
  11. Adjust the power level for the 'modulation conservation'
  12. Measure:
    • Forward power
    • Reflected power
  13. Turn the specified modulation on (if specified)
  14. Wait the specified dwell time
  15. Measure the AD convertors for the 'During' measurement
  16. Turn the modulation off
  17. Measure:
    • Voltage (See step 7)
    • Current
  18. Check if the test should be stopped, or Manual mode should be activated
  19. Go to the next frequency and continue at step 3.
  20. Deinitialize all the equipment that is used

Used Equipment[edit]

Device Type Optional Tab-blad
Signal Generator Needed Standard 1
Amplifier Needed Standard 1
Forward Power meter Optional Standard 1
Reflected Power meter Optional Standard 1
Coupler Needed when Forward or Reflected power meter is used Standard 1
Switch matrix Optional Standard 1
EUT Controller Optional Standard 1
AD Convertor Optional Standard 2
Cables Optional Cables

A voltage measuring device must be used. Which Device type is used for the measuring of the voltage is depending on the selection of the 'Voltage Measuring device' in the TSF-File of the test-configuration. The voltage measuring device can be one of:

Device Type Optional Tab-blad
Multimeter see note above Standard 1
Oscilloscope see note above Standard 1
Spectrum analyser see note above Standard 2
Sensor Power meter see note above Standard 2

If besides the voltage measuring, also the 'current' needs to be measured, the following equipment is also needed:

Device Type Optional Tab-blad
Sensor power meter Needed Standard 2
Current Sensor Needed Standard 2

Some random remarks:

  1. If the 'Sensor power meter' is used for measuring the Voltage or the current, this can be a real powermeter, but it can also be spectrum analyser that is controlled through a powermeter device driver. For most spectrum analysers, also a device driver to control the spectrum analyser as a powermeter is available.
  2. Depending on the used setup, a coupling device will be used to inject the generated power into the cables of the EUT. This 'coupling device' is not included in the list of used equipment.
  3. If the Sensor power meter is used as the voltage measuring device, it is not possible to also measure the current.