Standard testing of mixed signal components is generally implemented by digitizing an integer number of cycles of a waveform, and performing an FFT (if the number of collected points is of the form 2N), or a DFT. If the signal being measured does not include an integer number of cycles of the input, and the number of collected points is of the form 2N, a weighting function must be applied to suppress unwanted artifacts created by the analysis. This paper describes a mathematical approach, using a curve-fit algorithm, which permits the extraction of data in cases where the frequency of the tested signal bears a much less restrictive relationship to the sampling frequency. The implementation of the algorithm the LTX-Credence X-Series envision (Cadence) software is described.
Version: April 2012
Presented by: Solomon Max