<s>
Transcoder	B-Algorithm
and	O
Rate	O
Adaptation	O
Unit	O
or	O
TRAU	B-Algorithm
,	O
performs	O
transcoding	B-Algorithm
function	O
for	O
speech	O
channels	O
and	O
RA	O
(	O
Rate	O
Adaptation	O
)	O
for	O
data	O
channels	O
in	O
the	O
GSM	O
network	O
.	O
</s>
<s>
The	O
Transcoder/Rate	O
Adaptation	O
Unit	O
(	O
TRAU	B-Algorithm
)	O
is	O
the	O
data	O
rate	O
conversion	O
unit	O
.	O
</s>
<s>
for	O
half	B-Algorithm
rate	I-Algorithm
)	O
.	O
</s>
<s>
Transcoding	B-Algorithm
is	O
the	O
compression	O
of	O
speech	O
data	O
from	O
64	O
kbit/s	O
to	O
13/12.2/6.5	O
kbit/s	O
in	O
case	O
FR/EFR/HR	O
(	O
respectively	O
)	O
speech	O
coding	O
.	O
</s>
<s>
Rate	O
adaptation	O
without	O
transcoding	B-Algorithm
allows	O
Tandem	O
Free	O
Operation	O
(	O
TFO	O
)	O
,	O
allowing	O
the	O
original	O
encoded	O
speech	O
data	O
to	O
be	O
carried	O
in	O
a	O
64	O
kbit/s	O
channel	O
.	O
</s>
<s>
TFO	O
offers	O
benefits	O
because	O
transcoding	B-Algorithm
can	O
lead	O
to	O
a	O
degradation	O
of	O
speech	O
quality	O
and	O
requires	O
computational	O
resources	O
.	O
</s>
