Window function

Window function

In signal processing and statistics, a window function (also known as an apodization function or tapering function) is a mathematical function that is zero-valued outside of some chosen interval, normally symmetric around the middle of the interval, usually near a maximum in the middle, and usually tapering away from the middle. Mathematically, when another function or waveform/data-sequence is "multiplied" by a window function, the product is also zero-valued outside the interval: all that is left is the part where they overlap, the "view through the window". Equivalently, and in actual practice, the segment of data within the window is first isolated, and then only that data is multiplied by the window function values. Thus, tapering, not segmentation, is the main purpose of window funct

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enIn signal processing and statistics, a window function (also known as an apodization function or tapering function) is a mathematical function that is zero-valued outside of some chosen interval, normally symmetric around the middle of the interval, usually near a maximum in the middle, and usually tapering away from the middle. Mathematically, when another function or waveform/data-sequence is "multiplied" by a window function, the product is also zero-valued outside the interval: all that is left is the part where they overlap, the "view through the window". Equivalently, and in actual practice, the segment of data within the window is first isolated, and then only that data is multiplied by the window function values. Thus, tapering, not segmentation, is the main purpose of window funct
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Hanning.svg
Spectral leakage caused by %22windowing%22.svg
Window function and frequency response - Bartlett-Hann.svg
Window function and frequency response - Blackman-Harris.svg
Window function and frequency response - Blackman-Nuttall.svg
Window function and frequency response - Cosine.svg
Window function and frequency response - Exponential (60dB decay).svg
Window function and frequency response - Exponential (half window decay).svg
Window function and frequency response - flat top.svg
Window function and frequency response - GAP optimized Nuttall.svg
Window function and frequency response - Lanczos.svg
Window function and frequency response - Nuttall (continuous first derivative).svg
Window function and frequency response - Parzen.svg
Window function and frequency response - Rectangular.svg
Window function and frequency response - Welch.svg
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Kernel density estimation
Has abstract
enIn signal processing and statistics, a window function (also known as an apodization function or tapering function) is a mathematical function that is zero-valued outside of some chosen interval, normally symmetric around the middle of the interval, usually near a maximum in the middle, and usually tapering away from the middle. Mathematically, when another function or waveform/data-sequence is "multiplied" by a window function, the product is also zero-valued outside the interval: all that is left is the part where they overlap, the "view through the window". Equivalently, and in actual practice, the segment of data within the window is first isolated, and then only that data is multiplied by the window function values. Thus, tapering, not segmentation, is the main purpose of window functions. The reasons for examining segments of a longer function include detection of transient events and time-averaging of frequency spectra. The duration of the segments is determined in each application by requirements like time and frequency resolution. But that method also changes the frequency content of the signal by an effect called spectral leakage. Window functions allow us to distribute the leakage spectrally in different ways, according to the needs of the particular application. There are many choices detailed in this article, but many of the differences are so subtle as to be insignificant in practice. In typical applications, the window functions used are non-negative, smooth, "bell-shaped" curves. Rectangle, triangle, and other functions can also be used. A more general definition of window functions does not require them to be identically zero outside an interval, as long as the product of the window multiplied by its argument is square integrable, and, more specifically, that the function goes sufficiently rapidly toward zero.
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Window function
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enWindow function
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apps.dtic.mil/dtic/tr/fulltext/u2/a034956.pdf
web.archive.org/web/20190408141816/https:/apps.dtic.mil/dtic/tr/fulltext/u2/a034956.pdf
electronicsart.weebly.com/fftwindows.html
www.mathworks.com/help/signal/ref/flattopwin.html
www.mathworks.com/help/signal/ug/generalized-cosine-windows.html
practicalcryptography.com/miscellaneous/machine-learning/implementing-dolph-chebyshev-window/
zone.ni.com/reference/en-XX/help/371361B-01/lvanlsconcepts/char_smoothing_windows/
www.mathworks.com/help/signal/ref/taylorwin.html
www.mathworks.com/help/signal/ref/tukeywin.html
octave.sourceforge.net/signal/function/ultrwin.html
patentimages.storage.googleapis.com/4d/39/2a/cec2ae6f33c1e7/US6898235.pdf
www.ritec-eg.com/Library%20&%20Tools/Windowing-Leakage-Bin-Centering-Window-Noise-Factor.html
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Airy function
Anisotropy
Antenna (radio)
Apodization
Asymptotically equal
Autocorrelation
Basis function
Beamforming
Bessel function
Boxcar function
B-spline
Bump function
Category:Digital signal processing
Category:Fourier analysis
Category:Signal estimation
Category:Types of functions
Chebyshev polynomials
Curve fitting
Derivative
Diffraction
Digital filters
Dirichlet kernel
Discrete Fourier transform
Discrete-time Fourier transform
Exponential function
File:Hanning.svg
File:Spectral leakage caused by %22windowing%22.svg
File:Window function and frequency response - Approximate confined Gaussian (sigma t = 0.1).svg
File:Window function and frequency response - Bartlett-Hann.svg
File:Window function and frequency response - Blackman-Harris.svg
File:Window function and frequency response - Blackman-Nuttall.svg
File:Window function and frequency response - Confined Gaussian (sigma t = 0.1).svg
File:Window function and frequency response - Cosine.svg
File:Window function and frequency response - Dolph-Chebyshev (alpha = 5).svg
File:Window function and frequency response - DPSS (alpha = 2).svg
File:Window function and frequency response - DPSS (alpha = 3).svg
File:Window function and frequency response - Exponential (60dB decay).svg
File:Window function and frequency response - Exponential (half window decay).svg
File:Window function and frequency response - flat top.svg
File:Window function and frequency response - GAP optimized Nuttall.svg
File:Window function and frequency response - Gaussian (sigma = 0.4).svg
File:Window function and frequency response - Hamming (alpha = 0.53836, n = 0...N).svg
File:Window function and frequency response - Hann-Poisson (alpha = 2).svg
File:Window function and frequency response - Kaiser (alpha = 2).svg
File:Window function and frequency response - Kaiser (alpha = 3).svg
File:Window function and frequency response - Lanczos.svg
File:Window function and frequency response - Nuttall (continuous first derivative).svg
File:Window function and frequency response - Parzen.svg
File:Window function and frequency response - Planck-Bessel (epsilon = 0.1, alpha = 4.45).svg
File:Window function and frequency response - Planck-taper (epsilon = 0.1).svg
File:Window function and frequency response - Rectangular.svg
File:Window function and frequency response - Tukey (alpha = 0.5).svg
File:Window function and frequency response - Ultraspherical (mu = -0.5).svg
File:Window function and frequency response - Welch.svg
File:Window function and its Fourier transform – Blackman (n = 0...N).svg
File:Window function and its Fourier transform – Hann (n = 0...N).svg
File:Window function and its Fourier transform – Triangular (n = 0...N).svg
Finite impulse response
Fourier transform
Frequency estimation
Frequency spectrum
Function (mathematics)
Gaussian function
Gaussian window
Gravitational-wave astronomy
Hann function
Hill climbing
Interval (mathematics)
Isotropy
James Kaiser
Julius von Hann
Kaiser window
Kernel (statistics)
Kolmogorov–Zurbenko filter
Lanczos resampling
Lipót Fejér
M. S. Bartlett
Manifolds
Modal analysis
Modified Bessel function
Modified discrete cosine transform
Multitaper
Newton's method
Overlap–add method
Parabola
Partitions of unity
Piecewise
Planck's law
Pulse shaping
Quadratic polynomial
Radial function
Rectangular function
Richard W. Hamming
Short-time Fourier transform
Signal processing
Sinc function
Smooth function
Spectral concentration problem
Spectral leakage
Square integrable
Statistics
Tapering (mathematics)
Tapio Saramäki
Time-frequency representation
Ultraspherical polynomial
Uniform norm
Weight function
Weighting
Welch method
Window design method
Window function
SameAs
Aknafunktsioon
Fenêtrage
Fensterfunktion
Funció finestra
Funzione finestra
m.01kcm8
Okno czasowe
Q1404885
R1eg
Vensterfunctie
Ventana (función)
Vinduesfunktion
Window function
Віконна функція
Окно (весовая функция)
دالة الإطار
窓関数
窗函数
Subject
Category:Digital signal processing
Category:Fourier analysis
Category:Signal estimation
Category:Types of functions
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