How can measurements for multiple similar standards be done only once?

Discussion and questions regarding the Radiated Emission and Conducted Emission modules of RadiMation.
Post Reply
incognito
Posts: 235
Joined: 03 Feb 2012, 13:07

How can measurements for multiple similar standards be done only once?

Post by incognito »

The limits for industrial IEC 61000-6-4 are similar to FCC part 15.
For ISM we use for CE EN55011 group 1 and> 20 kV and for FCC part 18. Of this the limit for CE is a few dB lower than for FCC part 18.

We are using very big EUT's and we do not do a height scan and place the antenna at a distance of 1 m (with adjusted limits 20 dB higher than for 10 m) around the EUT because the EUT cannot rotate and due to lack of space around the EUT. At high EUT's the measurements are taken at two heights.

To save time for radiated emission it would be useful if CE and FCC could be run simultaneously. The problem is the RBW which is 120 kHz for CE and 100 kHz for FCC.

Is it possible to make a prescan with 120 kHz RBW with radimation and then select the peaks to be measured according to the strictest limit? Then, for industrial, the final measurement would be the QP for CE 61000-6-4 with 120 kHz and for FCC part 15 with 100 kHz.

For ISM, could the prescan be performed according to EN55011 and then perform the final measurement QP with 120 kHz and AV with 100 kHz? This saves a prescan per antenna position and per polarization direction. The number of antenna position can be up to 30 and then horizontal and vertical.

How can I perform what I described above with RadiMation?
User avatar
joro
Posts: 440
Joined: 24 Aug 2011, 09:55
Contact:

Re: How can measurements for multiple similar standards be done only once?

Post by joro »

With some small tips and tricks, it is indeed possible to do the measurements of these similar standards only once. It however does require that some manual interactions are needed, as it is not possible to do it fully automated according to all the standards.

As a general description, the following steps could be used to perform the measurement as you described:
  1. Configure a TSF file for a Multiband Radiated Emission test, that is accoording one of the standards, for example the: 'CE IEC 61000-6-4'. Configure the settings as you desire (like turntable angles, polarizations, heights, distance, testsite equipment, etc...)
  2. In the TSF select the strictest limit, and you probably want to select the 120 kHz RBW, to perform the prescan.
  3. Save the TSF (so you can use it on a later moment)
  4. Start the TSF, and perform the measurement on all the angles, heights and polarizations
  5. Once the prescan is finished, and the peaks are detected, the Multiband emission test is halted, so the end-user can review the peaks, and optionally add or remove peaks. At this moment, press close and save the test results.
  6. The EUT file is now shown again, with the prescan results of the measurements.
  7. The prescan test results is stored in a <EUT-FILENAME>.Txx file in the same directory as the EUT, also with the same name as the EUT file. Create a copy of the last <EUT-FILENAME>.Txx file, and increase the number in the .Txx extension. If you want to test for 3 standards, you have to make an additional copy again.
  8. In RadiMation, close the EUT file, and open it again. The list of performed tests in the EUT File will now also show the last test multiple times corresponding to the manually copied <EUT-FILENAME>.Txx files. Each of these test files now contain the state and measurement results, as it was measured at the end of the pre-scan phase.
  9. Open one of the test-results. I advise to update the contents of the Note, to clarify specify which 'standard' will be used to continue this measurement.
  10. On the left, the active testsite can be selected, this is initially '(none)' when the results are re-opened, however another test-site can be selected, which will then initialize and connect to all the equipment again.
  11. With the 'Limits' button, the corresponding limitline files for the standard that you are now performing the final measurement for, can be selected. Optionally the previously selected limitlines can be removed from the testresults.
  12. The list of detected peaks is shown below the graph, the final measurement on those detected peaks can be performed by selecting one or more peaks, and then click on the 'measure peak' button. The measurement will then be performed accoording the settings that are selected on the left side of the window. It is thus important to first manually select the desired RBW, Attenuator, detectors, etc.. before the 'Measure peaks' button is pressed.
  13. When all the peaks are measured, the test result can be closed and saved. Another previously copied testresult can be opened to perform the peak measurements with the slightly modified measurement settings. Just continue at step 9 again.
I do would like to advise to experiment and perform these steps a few times to get known to the procedure, before the real measurements are being performed, as you probably do not want to loose to much time during the real measurement (even though, these steps will give you a huge overall time improvement).

To conclude:
By manually copying the test result files into a separate <EUT-FILENAME>.Txx file, a copy of the test results is created, which is in not linked anymore to the original test result, it is a fully duplicated copy of the test. Those duplicated measurement results can then be used to perform additional measurements with slightly modified measurement settings.
Post Reply