When.com Web Search

Search results

  1. Results From The WOW.Com Content Network
  2. Multidimensional transform - Wikipedia

    en.wikipedia.org/wiki/Multidimensional_transform

    The 2D Z-transform, similar to the Z-transform, is used in multidimensional signal processing to relate a two-dimensional discrete-time signal to the complex frequency domain in which the 2D surface in 4D space that the Fourier transform lies on is known as the unit surface or unit bicircle.

  3. Discrete Fourier transform - Wikipedia

    en.wikipedia.org/wiki/Discrete_Fourier_transform

    Fourier transform (bottom) is zero except at discrete points. The inverse transform is a sum of sinusoids called Fourier series. Center-right: Original function is discretized (multiplied by a Dirac comb) (top). Its Fourier transform (bottom) is a periodic summation (DTFT) of the original transform. Right: The DFT (bottom) computes discrete ...

  4. Fourier transform - Wikipedia

    en.wikipedia.org/wiki/Fourier_transform

    Many of the standard properties of the Fourier transform are immediate consequences of this more general framework. [29] For example, the square of the Fourier transform, W 2, is an intertwiner associated with J 2 = −I, and so we have (W 2 f)(x) = f (−x) is the reflection of the original function f.

  5. DFT matrix - Wikipedia

    en.wikipedia.org/wiki/DFT_matrix

    The DFT is (or can be, through appropriate selection of scaling) a unitary transform, i.e., one that preserves energy. The appropriate choice of scaling to achieve unitarity is , so that the energy in the physical domain will be the same as the energy in the Fourier domain, i.e., to satisfy Parseval's theorem. (Other, non-unitary, scalings, are ...

  6. Convolution theorem - Wikipedia

    en.wikipedia.org/wiki/Convolution_theorem

    In mathematics, the convolution theorem states that under suitable conditions the Fourier transform of a convolution of two functions (or signals) is the product of their Fourier transforms. More generally, convolution in one domain (e.g., time domain ) equals point-wise multiplication in the other domain (e.g., frequency domain ).

  7. Fast Fourier transform - Wikipedia

    en.wikipedia.org/wiki/Fast_Fourier_transform

    A discrete Fourier analysis of a sum of cosine waves at 10, 20, 30, 40, and 50 Hz. A fast Fourier transform (FFT) is an algorithm that computes the Discrete Fourier Transform (DFT) of a sequence, or its inverse (IDFT). Fourier analysis converts a signal from its original domain (often time or space) to a representation in the frequency domain ...

  8. Fourier series - Wikipedia

    en.wikipedia.org/wiki/Fourier_series

    Fourier analysis. Related transforms. A Fourier series (/ ˈfʊrieɪ, - iər / [1]) is an expansion of a periodic function into a sum of trigonometric functions. The Fourier series is an example of a trigonometric series, but not all trigonometric series are Fourier series. [2] By expressing a function as a sum of sines and cosines, many ...

  9. Fourier analysis - Wikipedia

    en.wikipedia.org/wiki/Fourier_analysis

    Fourier transforms. In mathematics, Fourier analysis (/ ˈfʊrieɪ, - iər /) [1] is the study of the way general functions may be represented or approximated by sums of simpler trigonometric functions. Fourier analysis grew from the study of Fourier series, and is named after Joseph Fourier, who showed that representing a function as a sum of ...