Signal Processing Toolbox™

hann - Hann (Hanning) window

Syntax

w = hann(L)
w = hann(L,'sflag')

Description

w = hann(L) returns an L-point symmetric Hann window in the column vector w. L must be a positive integer. The coefficients of a Hann window are computed from the following equation.

The window length is .

w = hann(L,'sflag') returns an L-point Hann window using the window sampling specified by 'sflag', which can be either 'periodic' or 'symmetric' (the default). The 'periodic' flag is useful for DFT/FFT purposes, such as in spectral analysis. The DFT/FFT contains an implicit periodic extension and the periodic flag enables a signal windowed with a periodic window to have perfect periodic extension. When 'periodic' is specified, hann computes a length L+1 window and returns the first L points. When using windows for filter design, the 'symmetric' flag should be used.

Note   If you specify a one-point window (L=1), the value 1 is returned.

Examples

Create a 64-point Hann window and display the result in WVTool:

L=64;
wvtool(hann(L))

References

[1] Oppenheim, A.V., and R.W. Schafer, Discrete-Time Signal Processing, Prentice-Hall, 1989, pp. 447-448.

See Also

blackman, flattopwin, hamming, window, wintool, wvtool

hamming

hilbert