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sinusoid

A pure cosine or sine wave, A\cos(\omega n + \phi) -- the single building block every Fourier method decomposes a signal into.

A sinusoid is a signal of the exact form A\cos(\omega n+\phi) (or the sine version), set by an amplitude A, a frequency \omega, and a phase \phi. Every Fourier-based tool in this course (the DTFT, the DFT, the FFT) works by writing an arbitrary signal as a sum of sinusoids.

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signal
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