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Decompose signals into time-aligned components

The **Signal Multiresolution Analyzer** app is an interactive tool for
visualizing multilevel wavelet and empirical mode decompositions of real-valued 1-D signals
and comparing results. With the app, you can:

Access all the signals in the MATLAB

^{®}workspace.Adjust default parameters and generate multiple decompositions using

`modwt`

and`modwtmra`

(default) or`emd`

methods.Choose decomposition levels to include in the signal reconstruction.

Visualize and compare results.

Obtain frequency ranges of the decomposition levels. (See

`powerbw`

for more information.)Determine the relative energy of the signal across levels.

Export reconstructed signals and decompositions to your workspace.

Recreate the decomposition in your workspace by generating a MATLAB script.

MATLAB Toolstrip: On the

**Apps**tab, under**Signal Processing and Communications**, click**Signal Multiresolution Analyzer**.MATLAB command prompt: Enter

`signalMultiresolutionAnalyzer`

.

`Wavelet`

— Orthogonal wavelet family`sym`

(default) | `coif`

| `db`

| `fk`

Orthogonal wavelet family to use to generate the multiresolution analysis (default), specified as:

`sym`

— Symlets`coif`

— Coiflets`db`

— Daubechies wavelets`fk`

— Fejér-Korovkin wavelets

The `Wavelet`

parameter is applicable only for
generating a multiresolution analysis.

For more information about the wavelets, use the `waveinfo`

function. For example, to learn more about Daubechies wavelets,
enter `waveinfo('db')`

.

`Interpolation`

— Interpolation method`spline`

(default) | `pchip`

Interpolation method to use for envelope construction in empirical mode decomposition, specified as one of the following:

`spline`

— Cubic spline interpolation`pchip`

— Piecewise cubic Hermite interpolating polynomial method

The `Interpolation`

parameter is applicable only for
generating an empirical mode decomposition. You can change other options with the app
when creating empirical mode decompositions. For more information, see `emd`

.

To decompose more than one signal simultaneously, you can run multiple instances of the
**Signal Multiresolution Analyzer** app.

The **Signal Multiresolution Analyzer** uses `modwt`

and `modwtmra`

to generate the multiresolution
analysis and `emd`

to generate
the empirical mode decompositions.

[1] Donoho, David L., and Iain M.
Johnstone. “Ideal Spatial Adaptation by Wavelet Shrinkage.” *Biometrika*
81, no. 3 (September 1, 1994): 425–55. https://doi.org/10.1093/biomet/81.3.425.