User`s guide

Time-Varying Direct-Form II Transpose Filter
5-433
5Time-Varying Direct-Form II Transpose Filter
Purpose Apply a variable IIR filter to the input.
Library Filtering / Filter Designs
Description The Time-Varying Direct-Form II Transpose Filter block is a version of the
Direct-Form II Transpose Filter block whose filter coefficients can be updated
during the simulation. The block applies a direct-form II transposed IIR filter
to the top input (
In).
This is a canonical form that has the minimum number of delay elements. The
filter order is
max(m,n)-1.
An M-by-N sample-based matrix input is treated as M
∗N independent
channels, and an M-by-N frame-based matrix input is treated as N
independent channels. In both cases, the block filters each channel
independently over time, and the output has the same size and frame status as
the input.
The block’s two lower inputs (
Num and Den) specify the filter’s transfer function,
By default the filter coefficients are normalized by a
1
. To prevent
normalization by a
1
, deselect the Support non-normalized filters check box.
Filter Type
The Filter type parameter specifies whether the filter is an all-zero (FIR or
MA) filter, all-pole (AR) filter, or pole-zero (IIR or ARMA) filter:
y(k)
x(k)
ΣΣ
z
-1
Σ
z
-1
Σ
z
-1
z
n -1
(k) z
2
(k) z
1
(k)
. . .
b(m) b(2)b(3) b(1)
-a(n) -a(2)-a(3)
. . .
. . .
Hz()
Bz()
Az()
------------
b
1
b
2
z
1–
… b
m 1+
z
m 1–()–
+++
a
1
a
2
z
1–
… a
n 1+
z
n 1–()–
+++
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