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spectrum.cov

Covariance spectrum

Syntax

Description

Hs = spectrum.cov returns a default covariance spectrum object, Hs, that defines the parameters for the covariance spectral estimation algorithm. The covariance algorithm estimates the spectral content by fitting an auto-regressive (AR) linear prediction model of a given order to the signal.

Hs = spectrum.cov(order) returns a spectrum object, Hs with the specified order and the FFTLength determined using NextPow2. The default value for order is 4.

Hs = spectrum.cov(order,FFTLength) returns a covariance spectrum object, Hs with the order of the covariance model and the specified way of determining the FFTLength. Valid values of the FFTLength string are:

FFTLength string
Description
'InputLength'
Use the length of the input signal as the FFT length
'NextPow2'
Use the next power of 2 greater than the input signal length as the FFT length. This is the default value.
'UserDefined'
Use the FFT length provided as an input to the psd method or via a dspopts object. See dspopts for an example.

Examples

Define a fourth order auto-regressive model and view its power spectral density using the covariance algorithm.

See Also

dspdata, dspopts, spectrum, spectrum.burg, spectrum.mcov, spectrum.yulear, spectrum.periodogram, spectrum.welch, spectrum.mtm, spectrum.eigenvector, spectrum.music


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