RadiMation Application Note 124

Emission: measuring intermittent signals

One of the first important things to determine when doing a Emission test is to know the emission pattern from the device. The standard describes two general types:

• Continuous disturbances

Continuous interference arises when the source continuously emits are a given range of frequency's

Sources include

• Discontinuous disturbances

Specific audio breakthrough measurement not available

• Level or S/N measurement
• Selective level measurement
• SINAD or THD+N measurement
• Measurement of total harmonic distortion (THD)
• Modulation distoration analysis in line with IEC 60268-3
• Intermodulation measurement
• Dynamic intermodulation measurement
• DC voltage measurement
• Frequency, phase and group delay measurement
• Polarity test
• Crosstalk measurement
• Waveform function
• Measruement of time difference
• UPV-K6 expanded analysis function
• Psycho-acoustic measurement methods
• Speech and audio quality measurements (PESQ, PEAQ and POLQA)
• PDM bitstream analysis

These are just some of the measurements that are described in the R&S UPV Brochure and Datasheet. This example strengthens us in the fact that it is extremely complex to correctly integrate the needed functionalities from the equipment into a dedicated device driver.

Manually configuration, automated testing

There is however an easier and more flexible solution to integrate the measurement results of the audio breakthrough device in RadiMation. This is also the method that we suggest to use. During the setup of the EUT in the chamber, the EUT will be connected to the Audio Break Through measurement setup that also includes the audio breakthrough device. The test engineer will then also configure the audio breakthrough device to correctly measure the signal, and set all the settings of the audio breakthrough device manually to their correct and corresponding values. This allows the test engineer to configure the audio breakthrough device manually in such a way that the desired signal is measured with optimal settings. After this setup the test-engineer can start the EMC test in our RadiMation software. The RadiMation software will then request one or more of the needed measurement values of the audio breakthrough device for each tested RF frequency, and will plot these measurement values in the graphs within the RadiMation software. This is then the including the results of the Audio Break Through measurement.

Configurable AD Converted as Audio breakthrough device driver

In RadiMation we provide a ‘Configurable AD Convertor’ device driver, which can be used to retrieve a measurement value from another device (the audio breakthrough device). This device driver can be configured to send a GPIB command, wait for the response, and interpret the response to convert it to a number that is shown in the graph. This device driver allows to use multiple ‘channels’, so multiple values can be retrieved from the audio breakthrough device, and be reported in RadiMation as different graphs/values. We only need to determine the correct commands for the audio breakthrough device once, and specify them once in the ‘Configurable AD Convertor’ device driver. After this ‘Configurable AD Convertor’ device driver is configured, it can be reused during all the EMC tests that use the audio breakthrough device to perform the Audio Break Through measurement.

The big advantage of using the ‘Configurable AD Convertor’ device driver is that you have a lot of flexibility to control the setup and the measurement parameters, while it is very easy to use in RadiMation This ‘Configurable AD Convertor’ device driver’ is already available in the current RadiMation release.

As an example there is a forum topic which explains how it can be configured using a R&S UPV: [1]

Our reference to related items: #7568 and #7565.