spectrum.welch
Welch spectrum
Syntax
Hs = spectrum.welch
Hs = spectrum.welch(WindowName)
Hs = spectrum.welch(WindowName,SegmentLength)
Hs = spectrum.welch(WindowName,SegmentLength,OverlapPercent)
Description
Note
The use of spectrum.welch
is not recommended.
Use pwelch
instead.
Hs = spectrum.welch
returns
a default Welch spectrum object, Hs
, that defines
the parameters for Welch's averaged, modified periodogram spectral
estimation method. The object uses these default values.
Property Name | Default Value | Description |
---|---|---|
Cell
array containing |
| Cell array containing the window name or You can use |
|
| Valid 'Bartlett' 'Bartlett-Hann' 'Blackman' 'Blackman-Harris' 'Bohman' 'Chebyshev' 'Flat Top' 'Gaussian' 'Hamming' 'Hann' 'Kaiser' 'Nuttall' 'Parzen' 'Rectangular' 'Triangular' 'Tukey' 'User Defined' Window
names must be enclosed in single quotes, such as
See
|
|
| Length of each of the time-based segments into which the input signal is divided. A modified periodogram is computed on each segment and the average of the periodograms forms the spectral estimate. Choosing the segment length is a compromise between estimate reliability (shorter segments) and frequency resolution (longer segments). A long segment length produces better resolution while a short segment length produces more averages, and therefore a decrease in the variance. |
|
| Percent overlap between segments |
Hs = spectrum.welch(WindowName)
returns
a spectrum object, Hs
, using Welch's method with
the specified window and the default values for all other parameters.
To specify parameters for a window, use a cell array formatted as spectrum.welch({WindowName,winparam})
.
Hs = spectrum.welch(WindowName,SegmentLength)
returns
a spectrum object, Hs
with the specified segment
length.
Hs = spectrum.welch(WindowName,SegmentLength,OverlapPercent)
returns
a spectrum object, Hs
with the specified percentage
overlap between segments.
Note
See pwelch
for more information
on the Welch algorithm.
Examples
References
[1] harris, fredric. j. “On the Use of Windows for Harmonic Analysis with the Discrete Fourier Transform.” Proceedings of the IEEE®. Vol. 66 (January 1978).
Version History
Introduced before R2006a
See Also
periodogram
| pmtm
| pwelch