Ambient noise cancellation in frequency domain EMI measurement

In this paper, an advanced signal processing technique for measurements of electromagnetic interference from electronic devices will be presented. Lower and lower ambient noise is preferred in electromagnetic interference measurement. Not all the device producers can pay for darkroom measurement, because it real costs a lot. This method provides an opportunity to perform an electromagnetic interference measurement at a site polluted by electromagnetic ambient noise. Resulted from a real device under test, automatic measurement with this method that successfully cancels the ambient noise will be presented.