User`s guide

Dyadic Analysis Filter Bank
5-153
The bottom two outputs (y
n
and y
n+1
) share the same sample period,
bandwidth, and frame size because they originate at the same tree level.
Symmetric Tree. The symmetric structure shown below (Tree structure set to
Symmetric) has 2
n
outputs, where n is the Number of levels parameter value.
The sample rate and bandwidth of every output are reduced by a factor of 2
n
from the input sample rate and bandwidth. 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
.
HP
LP
↓2
↓2
HP
↓2
LP
↓2
HP
↓2
LP
↓2
u
HP: highpass filter with f
c
≈ 1/2 Nyquist
LP: lowpass filter with
f
c
≈ 1/2 Nyquist
↓2: downsample by 2
y
1
y
2
y
3
y
7
y
2
n
HP
↓2
LP
↓2
HP
↓2
LP
↓2
HP
↓2
LP
↓2
HP
↓2
LP
↓2
. . .
. . .
. . .
. . .
y
4
y
5
y
6
Symmetric Fi
l
ter Ban
k
, n Leve
l
s
T
si
=T
s
T
so
=(2
n
)T
s
for all 2
n
outputs
T
so k,
2
n
()T
s
1 k 2
n
≤≤()=
BW
k
BW
2
n
----------
1 k 2
n
≤≤()=