FFT Fast Fourier Transform

Abstract—Spectral warping is a digital signal processing trans-form which shifts the frequencies contained within a signal along the frequency axis. The Fourier transform coefficients of a warped signal correspond to frequency-domain ‘samples ’ of the original signal which are unevenly spaced along the frequency axis. This property allows the technique to be efficiently used for DSP-based analog and mixed-signal testing. The analysis and application of spectral warping for test signal generation, response analysis, filter design, frequency response evaluation, etc. are discussed in this paper along with examples of the software and hardware implementation. Index Terms—Analog and mixed-signal circuits, chirp, digital signal generation and analysis, electronic testing