<s>
A	O
soft-in	B-Error_Name
soft-out	I-Error_Name
(	O
SISO	O
)	O
decoder	O
is	O
a	O
type	O
of	O
soft-decision	B-Error_Name
decoder	I-Error_Name
used	O
with	O
error	B-Error_Name
correcting	I-Error_Name
codes	I-Error_Name
.	O
</s>
<s>
Typically	O
,	O
the	O
soft	O
output	O
is	O
used	O
as	O
the	O
soft	O
input	O
to	O
an	O
outer	O
decoder	O
in	O
a	O
system	O
using	O
concatenated	O
codes	O
,	O
or	O
to	O
modify	O
the	O
input	O
to	O
a	O
further	O
decoding	O
iteration	O
such	O
as	O
in	O
the	O
decoding	O
of	O
turbo	B-Error_Name
codes	I-Error_Name
.	O
</s>
<s>
Examples	O
include	O
the	O
BCJR	B-Error_Name
algorithm	I-Error_Name
and	O
the	O
soft	O
output	O
Viterbi	O
algorithm	O
.	O
</s>
