Page 177 - Digital Signal and Image Processing Using MATLAB
P. 177
#! 2 -
0 - -
-
-
18
16
14
m=3
12
10
8
6
4
2
0
−0.5 −0.4 −0.3 −0.2 −0.1 0 0.1 0.2 0.3 0.4 0.5
0
M 4 #
%
1
*4
1 - 5=
+
'
+
+ %%> ' %%
+
+
*
- -
+ * %
1
'3
-
(
%
*
4
+
% - %
4
5
-
% - %+ , =% % -
+
5=
+ *
%
1
-
Decimation
Prefiltering {
1
1−z −M M
1−z −1
⇓
1
M 1−z −1
1−z −1
M
=
-
-
% %
+ *
%
%
> %'
+
+
1 -
+
4 5
4 J5%
+ %
+
+
%
4%5'+ %
4%5 '
C
+
4%5 4% 5 JO 4%5
3
'+ +
/
-
<4 5 J%
+ %
+
+
+
%
4%5'+ %
,4%5 '
C
4
4%5 ,4%5 , J% 5
'+ +
+ %% &
*
