Cryptography Reference
In-Depth Information
Figure 8.4 - Performance of the Chase-Pyndiah algorithm in the turbo decoding of
different 1-correcting codes (2-PSK on a Gaussian channel, 8 iterations,
q
=5
).
(Source
P. Adde, Electronics Department, ENST Bretagne).
Step 3: Let
s
be the vector of the hard decisions of
r
.Let
M
1
be the
accumulated metrics associated with the
n
•
k
first values of
r
.Thatis,
−
s
=
H
s
1
0
s
2
s
n−k
...
00
...
Let
M
2
be the accumulated metrics associated with
s
in the
k
last values
of
r
. The total accumulated metric is then
M
=
M
1
+
M
2
.
