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spectrum.periodogram

Periodogram spectrum

Syntax

Hs = spectrum.periodogram
Hs = spectrum.periodogram(winname)
Hs = spectrum.periodogram({winname,winparameter})

Description

    Note:   The use of spectrum.periodogram is not recommended. Use periodogram instead.

Hs = spectrum.periodogram returns a default periodogram spectrum object, Hs, that defines the parameters for the periodogram spectral estimation method. This default object uses a rectangular window and a default FFT length equal to the next power of 2 (NextPow2) that is greater than the input length.

Hs = spectrum.periodogram(winname) returns a spectrum object, Hs, that uses the specified window. If the window uses an optional associated window parameter, it is set to the default value. This object uses the default FFT length.

Hs = spectrum.periodogram({winname,winparameter}) returns a spectrum object, Hs, that uses the specified window and optional associated window parameter, if any. You specify the window and window parameter in a cell array with a windowname string and the parameter value. This object uses the default FFT length.

Valid windowname strings are:

'Bartlett'
'Bartlett-Hanning'
'Blackman'
'Blackman-Harris'
'Bohman'
'Chebyshev'
'Flat Top'
'Gaussian'
'Hamming'
'Hann'
'Kaiser'
'Nuttall'
'Parzen'
'Rectangular'
'Triangular'
'Tukey'
'User Defined'

See window and the corresponding window function page for window parameter information.

You can use set to change the value of the additional parameter or to define the MATLAB® expression and parameters for a user-defined window (see spectrum for information on using set).

    Note   Window names must be enclosed in single quotes, such as spectrum.periodogram('tukey') or spectrum.periodogram({'tukey',0.7}).

    Note   See periodogram for more information on the periodogram algorithm.

Examples

Define a cosine of 200 Hz, add noise and view its spectral content using the periodogram spectral estimation technique.

Fs=1000;
t=0:1/Fs:.3;
x=cos(2*pi*t*200)+randn(size(t));
Hs=spectrum.periodogram;	     % Use default values
psd(Hs,x,'Fs',Fs)

References

[1] Harris, F. J. "On the Use of Windows for Harmonic Analysis with the Discrete Fourier Transform." Proceedings of the IEEE®. Vol. 66 (January 1978).

See Also

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