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Spectral Comparison
A Spectral Comparison is a quantitative comparison between two frequency spectra. It is generated by
subtracting the values of one spectrum (Test View) from the values of the second spectrum (Reference
View) at each frequency. The Compare Spectral node allows you to observe and compare two Spectral
Scans with same resolution bandwidth and overlapping frequency range eventhough they may have
different frequency ranges e.g.: Spectral 1: 10 MHz - 80 MHz and Spectral 2: 30 MHz - 120 MHz.
A common use for this is to compare the spectral of a production device with the prototype device. This
is especially important for conformance testing, where a prototype has received EMC approval and you
want to compare production units to it. You would link the prototype
spectrum to the reference node and compare the spectra from
various production units against it by linking them to the test node.
Add Spectral Comparison node to Project node (please refer to
page 36
). Node settings window automatically opens. After you
click OK, Spectral Comparison window opens. Go to the Spectral
View. Select the data from the datalist that you want to subtract
from and click & drag & drop it on to Test View. Repeat these
steps for the second data and drop it on to Reference View. Click
Compare Spectral View tab and mouse over the graph to analyze
the difference.
EMxpert Software
Spectral Comparison
