<s>
The	O
Grand	B-Device
Alliance	I-Device
(	O
GA	O
)	O
was	O
a	O
consortium	B-Application
created	O
in	O
1993	O
at	O
the	O
behest	O
of	O
the	O
Federal	O
Communications	O
Commission	O
(	O
FCC	O
)	O
to	O
develop	O
the	O
American	O
digital	B-Application
television	I-Application
(	O
SDTV	B-Device
,	O
EDTV	O
)	O
and	O
HDTV	B-Device
specification	O
,	O
with	O
the	O
aim	O
of	O
pooling	O
the	O
best	O
work	O
from	O
different	O
companies	O
.	O
</s>
<s>
The	O
Grand	B-Device
Alliance	I-Device
DTV	B-Application
system	O
is	O
the	O
basis	O
for	O
the	O
ATSC	B-Device
standard	I-Device
.	O
</s>
<s>
advantages	O
of	O
all	O
of	O
the	O
previously	O
proposed	O
terrestrial	O
digital	O
HDTV	B-Device
systems	O
.	O
</s>
<s>
At	O
the	O
time	O
of	O
its	O
inception	O
,	O
the	O
Grand	B-Device
Alliance	I-Device
HDTV	B-Device
system	O
was	O
specified	O
to	O
include	O
:	O
</s>
<s>
Flexible	O
picture	O
formats	O
with	O
a	O
header/Descriptor	O
approach	O
,	O
allowing	O
the	O
inclusion	O
of	O
both	O
1050	O
and	O
787.5	O
raster	B-Algorithm
formats	I-Algorithm
.	O
</s>
<s>
Progressive	B-Device
scanning	I-Device
and	O
square	O
pixel	B-Algorithm
capabilities	O
in	O
both	O
raster	B-Algorithm
formats	I-Algorithm
.	O
</s>
<s>
Interlaced	O
scanning	O
and	O
rectangular	B-Algorithm
pixel	I-Algorithm
formats	O
.	O
</s>
<s>
Video	O
compression	O
based	O
on	O
MPEG-2	B-Algorithm
,	O
with	O
additional	O
syntax	O
elements	O
that	O
represent	O
contributions	O
from	O
each	O
previously	O
proposed	O
system	O
.	O
</s>
<s>
Candidate	O
transmission	O
approaches	O
included	O
QAM	B-Device
,	O
Spectrally-Shaped	O
QAM	B-Device
,	O
6	O
VSB	O
(	O
with	O
trellis	O
code	O
)	O
and	O
4/2	O
VSB	O
.	O
</s>
<s>
COFDM	B-Protocol
had	O
been	O
proposed	O
by	O
third	O
parties	O
,	O
but	O
was	O
rejected	O
as	O
not	O
being	O
mature	O
,	O
and	O
not	O
offering	O
fringe-area	O
coverage	O
equivalent	O
to	O
analog	O
transmission	O
.	O
</s>
<s>
In	O
the	O
end	O
,	O
1080	O
,	O
720	O
and	O
480-line	O
resolutions	O
were	O
implemented	O
at	O
various	O
aspect	O
ratios	O
and	O
frame	O
rates	O
,	O
with	O
progressive	O
and	O
interlaced	O
scanning	O
(	O
the	O
so-called	O
"	O
18	O
formats	O
"	O
)	O
,	O
together	O
with	O
8-VSB	B-Device
modulation	O
and	O
Dolby	O
AC-3	O
audio	O
.	O
</s>
<s>
The	O
choice	O
of	O
8-VSB	B-Device
was	O
later	O
criticised	O
by	O
several	O
groups	O
as	O
being	O
inferior	O
to	O
COFDM	B-Protocol
under	O
conditions	O
of	O
multipath	O
interference	O
.	O
</s>
<s>
With	O
MUSICAM	O
originally	O
faltering	O
during	O
GA	O
testing	O
,	O
the	O
GA	O
issued	O
a	O
statement	O
finding	O
the	O
MPEG-2	B-Algorithm
audio	O
system	O
to	O
be	O
"	O
essentially	O
equivalent	O
"	O
to	O
Dolby	O
,	O
but	O
only	O
after	O
the	O
Dolby	O
selection	O
had	O
been	O
made	O
.	O
</s>
<s>
1997	O
-	O
Academy	O
of	O
Television	O
Arts	O
&	O
Sciences	O
presents	O
Primetime	O
Engineering	O
Emmy	O
Award	O
to	O
Grand	B-Device
Alliance	I-Device
companies	O
for	O
developing	O
and	O
standardizing	O
the	O
transmission	O
and	O
technology	O
for	O
digital	B-Application
TV	I-Application
.	O
</s>
