User`s guide

Dyadic Analysis Filter Bank
5-152
functions in the Wavelet Toolbox (see the Wavelet Toolbox documentation for
more information).
Tree Structure
The Tree structure parameter specifies an asymmetric (or wavelet) tree, as
shown above, or a symmetric structure, as shown below. Note that the
symmetric structure decomposes both the high- and low-frequency subbands at
each level, whereas the asymmetric structure only decomposes the
low-frequency bands.
Asymmetric Tree. The asymmetric structure in the first figure (Tree structure
set to
Asymmetric) has n+1 outputs, where n is the Number of levels
parameter value. The sample rate and bandwidth of the top output are half the
input sample rate and bandwidth. The sample rate and bandwidth of each
additional output (except the last) are half that of the output from the previous
level. In general, for an input with sample period T
si
=T
s
, and bandwidth BW,
output y
k
has sample period T
so,k
and bandwidth BW
k
.
Note that in frame-based mode, the change in the sample period of output y
k
is
reflected by its frame size, M
o,k
, rather than by its frame rate.
T
so k,
2
k
()T
s
1 kn≤≤()
2
n
()T
s
kn1+=()





=
BW
k
BW
2
k
----------
1 kn≤≤()
BW
2
n
----------
kn1+=()







=
M
ok,
M
i
2
k
-------
1 kn≤≤()
M
i
2
n
-------
kn1+=()









=