<s>
The	O
Enhanced	O
Digital	O
Access	O
Communication	O
System	O
(	O
EDACS	B-Algorithm
)	O
is	O
a	O
radio	O
communications	O
protocol	O
and	O
product	O
family	O
invented	O
in	O
the	O
General	O
Electric	O
Corporation	O
in	O
the	O
mid	O
1980s	O
.	O
</s>
<s>
Childress	O
and	O
the	O
team	O
demonstrated	O
that	O
a	O
smart	O
controller	O
could	O
be	O
adapted	O
to	O
a	O
variety	O
of	O
applications	O
,	O
but	O
his	O
interest	O
was	O
really	O
in	O
fault	B-General_Concept
tolerance	I-General_Concept
.	O
</s>
<s>
The	O
competition	O
dealt	O
with	O
fault	B-General_Concept
tolerance	I-General_Concept
by	O
means	O
of	O
the	O
"	O
brute	O
force	O
and	O
ignorance	O
"	O
approach	O
,	O
deploying	O
double	O
the	O
hardware	O
for	O
their	O
controllers	O
,	O
and	O
interconnecting	O
them	O
with	O
massive	O
and	O
problematic	O
relay	O
banks	O
.	O
</s>
<s>
The	O
EDACS	B-Algorithm
system	O
architecture	O
supported	O
large	O
communications	O
footprints	O
.	O
</s>
<s>
By	O
making	O
the	O
GETC	O
's	O
"	O
trunk	O
"	O
among	O
themselves	O
,	O
one	O
GETC	O
per	O
channel	O
,	O
the	O
system	O
was	O
designed	O
to	O
be	O
inherently	O
fault-tolerant	B-General_Concept
.	O
</s>
<s>
The	O
EDACS	B-Algorithm
system	O
continues	O
to	O
be	O
sold	O
and	O
supports	O
a	O
sizable	O
portion	O
of	O
the	O
market	O
today	O
for	O
the	O
public	O
safety	O
,	O
public	O
transit	O
,	O
and	O
industrial	O
two-way	O
radio	O
communications	O
field	O
.	O
</s>
<s>
EDACS	B-Algorithm
was	O
developed	O
in	O
competition	O
with	O
Motorola	O
's	O
Smartnet	O
trunking	O
system	O
.	O
</s>
<s>
EDACS	B-Algorithm
has	O
the	O
largest	O
customer	O
base	O
of	O
any	O
technology	O
in	O
M/A	O
-COM	O
'	O
s	O
portfolio	O
(	O
i.e.	O
</s>
<s>
EDACS	B-Algorithm
,	O
OpenSky	O
,	O
P25	O
and	O
TETRA	O
)	O
.	O
</s>
<s>
Over	O
500	O
large-scale	O
EDACS	B-Algorithm
radio	O
systems	O
have	O
been	O
sold	O
-	O
with	O
the	O
State	O
of	O
Florida	O
being	O
the	O
largest	O
.	O
</s>
<s>
Hundreds	O
of	O
thousands	O
of	O
radios	O
have	O
been	O
sold	O
to	O
function	O
on	O
these	O
EDACS	B-Algorithm
systems	O
.	O
</s>
<s>
ETrunker	O
is	O
a	O
modification	O
to	O
the	O
Trunker	O
code	O
to	O
work	O
on	O
the	O
EDACS	B-Algorithm
control	O
channel	O
.	O
</s>
<s>
The	O
first	O
digital	O
voice	O
mode	O
developed	O
for	O
EDACS	B-Algorithm
was	O
GE	O
's	O
Voice	O
Guard	O
,	O
utilizing	O
sub-band	B-Algorithm
coding	I-Algorithm
for	O
its	O
datastream	O
at	O
a	O
rate	O
of	O
9600	O
bps	O
.	O
</s>
<s>
AEGIS	O
was	O
the	O
second	O
generation	O
EDACS	B-Algorithm
digital	O
voice	O
mode	O
,	O
made	O
once	O
again	O
by	O
GE	O
,	O
with	O
Adaptive	O
Multiband	O
Encoding	O
as	O
its	O
coding	O
scheme	O
.	O
</s>
<s>
ProVoice	O
is	O
Tyco	O
Electronics	O
 '	O
(	O
formerly	O
M/A	O
-COM	O
,	O
Ericsson	O
and	O
GE	O
)	O
implementation	O
of	O
IMBE	O
digital	O
modulation	O
for	O
radio	O
communications	O
,	O
being	O
the	O
third	O
generation	O
of	O
EDACS	B-Algorithm
digital	O
voice	O
.	O
</s>
<s>
It	O
is	O
not	O
APCO-25	O
compliant	O
,	O
but	O
does	O
use	O
the	O
same	O
IMBE	O
vocoder	B-Application
developed	O
by	O
Digital	O
Voice	O
Systems	O
,	O
Inc	O
.	O
(	O
DVSI	O
)	O
.	O
</s>
