<s>
Operational	B-Device
Display	I-Device
Systems	I-Device
are	O
systems	O
used	O
for	O
tracking	O
the	O
status	O
of	O
multiple	O
objects	O
in	O
avionics	O
.	O
</s>
<s>
Operational	B-Device
Display	I-Device
Systems	I-Device
are	O
usually	O
being	O
developed	O
by	O
large	O
countries	O
 '	O
civil	O
aviation	O
authorities	O
(	O
such	O
as	O
the	O
Federal	O
Aviation	O
Administration	O
in	O
the	O
United	O
States	O
,	O
or	O
the	O
main	O
Service	O
Providers	O
in	O
Europe	O
,	O
such	O
as	O
DFS	O
,	O
NATS	O
,	O
DSNA	O
,	O
ENAIRE	O
,	O
MUAC	O
,	O
etc.	O
,	O
coordinated	O
by	O
Eurocontrol	O
in	O
Europe	O
)	O
,	O
with	O
inputs	O
from	O
technology	O
companies	O
and	O
air	B-Application
traffic	I-Application
controllers	O
associations	O
.	O
</s>
<s>
Air	B-Application
traffic	I-Application
control	I-Application
systems	I-Application
gradually	O
evolved	O
from	O
the	O
old	O
sweeping	O
radar	B-Application
to	O
modern	O
computer-driven	O
systems	O
showing	O
maps	O
,	O
weather	O
information	O
,	O
aircraft	O
routes	O
and	O
digitized	O
radar	B-Application
tracks	O
on	O
an	O
ergonomically-designed	O
console	O
.	O
</s>
<s>
Whereas	O
in	O
the	O
past	O
the	O
information	O
came	O
only	O
from	O
a	O
radar	B-Application
,	O
current	O
systems	O
use	O
inputs	O
from	O
a	O
variety	O
of	O
sources	O
.	O
</s>
<s>
Radar	B-Application
is	O
still	O
used	O
(	O
multiple	O
sources	O
instead	O
of	O
just	O
one	O
)	O
,	O
but	O
is	O
now	O
complemented	O
by	O
transponder	B-Architecture
data	O
(	O
the	O
aircraft	O
sending	O
out	O
information	O
regarding	O
altitude	B-Application
and	O
identifications	O
)	O
and	O
soon	O
satellite	B-Application
data	O
(	O
for	O
more	O
accurate	O
positioning	O
and	O
overseas	O
navigation	O
)	O
.	O
</s>
<s>
As	O
most	O
data	O
is	O
now	O
digital	O
,	O
this	O
opens	O
the	O
way	O
for	O
extra	O
functionalities	O
to	O
be	O
embedded	O
in	O
the	O
modern	O
Operational	B-Device
Display	I-Device
System	I-Device
,	O
such	O
as	O
trajectory	O
prediction	O
,	O
conflict	O
warnings	O
,	O
traffic	O
flow	O
management	O
,	O
arrival	O
optimisation	O
,	O
etc	O
.	O
</s>
<s>
Two	O
separate	O
competing	O
systems	O
are	O
currently	O
operating	O
within	O
the	O
US	O
,	O
Common	O
ARTS	O
(	O
Automated	O
Radar	B-Application
Terminal	O
System	O
(	O
Lockheed	O
Martin	O
)	O
)	O
and	O
STARS	O
(	O
Raytheon	O
)	O
,	O
with	O
Common	O
ARTS	O
operating	O
at	O
the	O
busiest	O
facilities	O
(	O
New	O
York	O
,	O
Dallas	O
,	O
Atlanta	O
,	O
Southern	O
California	O
,	O
Chicago	O
,	O
Washington	O
D.C.	O
area	O
,	O
Denver	O
,	O
St.	O
Louis	O
,	O
Minneapolis	O
and	O
San	O
Francisco	O
area	O
)	O
within	O
the	O
US	O
.	O
</s>
<s>
On	O
the	O
display	O
side	O
,	O
the	O
round	O
radar	B-Application
is	O
being	O
replaced	O
by	O
computer-driven	O
cathode	B-Device
ray	I-Device
tubes	I-Device
,	O
which	O
now	O
are	O
being	O
replaced	O
by	O
modern	O
LCD	B-Device
flat	O
screens	O
in	O
en	O
route	O
systems	O
.	O
</s>
<s>
However	O
a	O
great	O
many	O
US	O
Air	B-Application
Traffic	I-Application
TRACON	O
facilities	O
and	O
Towers	O
still	O
use	O
the	O
older	O
cathode	B-Device
ray	I-Device
tube	I-Device
technology	O
.	O
</s>
<s>
Towers	O
are	O
slowly	O
replacing	O
old	O
DBrite	O
(	O
cathode	O
ray	O
type	O
remote	O
displays	O
)	O
with	O
an	O
LCD	B-Device
type	O
manufactured	O
by	O
Barco	O
.	O
</s>
