FAQs from Rohde & Schwarz

EMC32: Interactive data reduction, difference between "After data reduction" and "Before final measurements".

Question

In the menu "Data Reduction" of EMI Auto Test, there are two buttons for activating the "interactive data reduction". I would like to know the exact differences between "After Data Reduction" and "Before Final Meas". I couldn't find a plausible explanation.

Answer

In basically, in data reduction, the number of frequency points from the pre-measurement should be reduced as far as possible in order to save as much time as possible for the following measurement steps. Therefore, the data reduction provides several automatic data reduction algorithms in the data reduction dialog.

In addition, EMC32 offers "Interactive Data Reduction". If activated, the results can be revised again after the automatic data reductiion. For this purpose, the test is interrupted after the automatic data reduction has completed, so that you can edit the list of critical frequencies. For example, you can delete a frequency from the list if it should not to be considered further. You can also add frequency points manually if they are of special interest to you, although they were not found in the automatic data reduction process.

This function is not only available directly after the automatic data reduction, but also at a later point in time, before the final measurement. If this function is activated, you can edit the results in the last test phase, typically after maximization, again. Some points will be closer to limit line than before, others cannot be further maximized, they may be irrelevant for you for the further processing. Usually, this step is used to remove irrelevant points so that they are not included in the final measurement.

To put it simply, you can say: Both features offer you more flexibility in the test run. From a technical point of view it is the same functionality. If activates, it allows an interaction at different stages of the Test.