<s>
ASR-9	B-Algorithm
is	O
an	O
airport	O
surveillance	O
radar	O
system	O
admitted	O
into	O
the	O
National	O
Airspace	O
System	O
(	O
NAS	O
)	O
,	O
to	O
be	O
utilized	O
by	O
the	O
Federal	O
Aviation	O
Administration	O
to	O
monitor	O
civilian	O
and	O
commercial	O
air	O
traffic	O
within	O
the	O
United	O
States	O
.	O
</s>
<s>
Developed	O
by	O
Westinghouse	O
,	O
ASR-9	B-Algorithm
was	O
the	O
first	O
radar	O
system	O
to	O
display	O
air	O
traffic	O
,	O
and	O
weather	O
conditions	O
simultaneously	O
.	O
</s>
<s>
The	O
ASR-9	B-Algorithm
is	O
mainly	O
intended	O
to	O
monitor	O
and	O
track	O
aircraft	O
below	O
25,000	O
ft	O
and	O
within	O
forty	O
to	O
sixty	O
nautical	O
miles	O
from	O
the	O
airport	O
of	O
operation	O
.	O
</s>
<s>
The	O
ASR	O
radar	O
systems	O
were	O
widely	O
used	O
where	O
an	O
advanced	O
radar	O
system	O
was	O
needed	O
,	O
consisting	O
of	O
135	O
different	O
ASR-9	B-Algorithm
operating	O
locations	O
around	O
the	O
U.S.	O
</s>
<s>
The	O
FAA	O
is	O
currently	O
working	O
to	O
upgrade	O
the	O
remaining	O
ASR-9	B-Algorithm
radar	O
sites	O
to	O
a	O
modernized	O
digital	O
version	O
known	O
as	O
the	O
ASR-11	B-Algorithm
.	O
</s>
<s>
At	O
the	O
time	O
of	O
the	O
ASR-9	B-Algorithm
installment	O
,	O
the	O
system	O
was	O
a	O
significant	O
improvement	O
over	O
the	O
S-band	B-Algorithm
ASR	O
radars	O
being	O
used	O
by	O
airports	O
.	O
</s>
<s>
The	O
ASR-9	B-Algorithm
utilized	O
a	O
dual	O
beam	O
antenna	O
,	O
a	O
dual	O
channel	O
antenna	O
,	O
a	O
linear-wide	O
range	O
receiver	O
and	O
new	O
digital	O
processing	O
equipment	O
.	O
</s>
<s>
The	O
processor	O
installed	O
on	O
the	O
ASR-9	B-Algorithm
was	O
far	O
more	O
advanced	O
than	O
processors	O
that	O
had	O
been	O
used	O
on	O
previous	O
models	O
.	O
</s>
<s>
Combining	O
all	O
of	O
the	O
upgraded	O
components	O
,	O
the	O
ASR-9	B-Algorithm
provided	O
a	O
significantly	O
improved	O
ability	O
to	O
detect	O
aircraft	O
in	O
the	O
presence	O
of	O
ground	O
clutter	O
,	O
or	O
weather	O
clutter	O
such	O
as	O
torrential	O
rains	O
.	O
</s>
<s>
The	O
new	O
and	O
improved	O
processor	O
on	O
the	O
ASR-9	B-Algorithm
also	O
enhances	O
the	O
ability	O
to	O
detect	O
hazardous	O
weather	O
conditions	O
that	O
could	O
affect	O
flight	O
,	O
landing	O
and	O
take	O
off	O
of	O
various	O
aircraft	O
.	O
</s>
<s>
A	O
new	O
solid	O
state	O
design	O
and	O
Remote	O
Maintenance	O
Monitoring	O
significantly	O
improved	O
the	O
overall	O
availabilities	O
of	O
the	O
ASR-9	B-Algorithm
,	O
as	O
well	O
as	O
lowering	O
the	O
monthly	O
operation	O
costs	O
.	O
</s>
<s>
When	O
Westinghouse	O
first	O
started	O
development	O
of	O
the	O
ASR-9	B-Algorithm
,	O
it	O
was	O
primarily	O
to	O
upgrade	O
the	O
aging	O
ASR-4	O
,	O
-5	O
and	O
-6	O
radar	O
equipment	O
at	O
locations	O
that	O
did	O
not	O
receive	O
the	O
previous	O
version	O
,	O
the	O
ASR-8	O
.	O
</s>
<s>
The	O
ASR-9	B-Algorithm
monitoring	O
system	O
was	O
formally	O
designated	O
by	O
the	O
FAA	O
to	O
be	O
used	O
as	O
a	O
Primary	O
Radar	O
replacement	O
,	O
as	O
well	O
as	O
a	O
live	O
weather	O
condition	O
monitor	O
utilized	O
from	O
the	O
Air	O
Traffic	O
Control	O
tower	O
.	O
</s>
<s>
ASR-9	B-Algorithm
was	O
the	O
first	O
Radar	O
System	O
to	O
enable	O
the	O
detection	O
of	O
a	O
moving	O
target	O
with	O
circular	O
polarization	O
,	O
therefore	O
significantly	O
enhancing	O
the	O
ability	O
to	O
locate	O
aircraft	O
in	O
various	O
weather	O
conditions	O
.	O
</s>
<s>
The	O
Federal	O
Aviation	O
Administration	O
has	O
chosen	O
different	O
35	O
sites	O
around	O
the	O
United	O
States	O
to	O
receive	O
a	O
Weather	O
Systems	O
Processor	O
(	O
WSP	O
)	O
upgrade	O
to	O
be	O
added	O
to	O
the	O
existing	O
ASR-9	B-Algorithm
'	O
s	O
.	O
</s>
<s>
The	O
Weather	O
Systems	O
Processor	O
also	O
improved	O
the	O
ASR-9	B-Algorithm
'	O
s	O
accuracy	O
of	O
precipitation	O
reflectivity	O
measurements	O
taken	O
by	O
eliminating	O
the	O
amount	O
of	O
ground	O
clutter	O
picked	O
up	O
by	O
the	O
radar	O
sweeps	O
.	O
</s>
<s>
The	O
WSP	O
provided	O
a	O
velocity	O
imagery	O
,	O
as	O
well	O
as	O
full	O
resolution	O
reflectivity	O
that	O
extends	O
all	O
the	O
way	O
to	O
the	O
end	O
of	O
the	O
ASR-9	B-Algorithm
'	O
s	O
monitor	O
range	O
of	O
sixty	O
nautical	O
miles	O
.	O
</s>
<s>
Launching	O
the	O
upgrade	O
program	O
for	O
the	O
ASR-9	B-Algorithm
'	O
s	O
radar	O
processor	O
will	O
ultimately	O
enhance	O
the	O
amount	O
of	O
weather	O
data	O
the	O
computer	O
can	O
process	O
,	O
leading	O
to	O
an	O
even	O
greater	O
weather	O
surveillance	O
range	O
of	O
up	O
to	O
one	O
hundred	O
twenty	O
nautical	O
miles	O
.	O
</s>
<s>
The	O
antenna	O
used	O
on	O
the	O
ASR-9	B-Algorithm
was	O
a	O
state	O
of	O
the	O
art	O
horned	O
shaped	O
reflector	O
that	O
forms	O
two	O
cosecant-squared	B-Algorithm
beams	O
to	O
allow	O
high	O
elevation	O
gain	O
,	O
as	O
well	O
as	O
coverage	O
up	O
to	O
forty-two	O
degrees	O
in	O
elevation	O
coverage	O
.	O
</s>
<s>
The	O
two	O
beams	O
that	O
pulse	O
from	O
the	O
ASR-9	B-Algorithm
are	O
nearly	O
identical	O
;	O
however	O
,	O
a	O
minimal	O
displacement	O
in	O
height	O
between	O
the	O
two	O
beams	O
causes	O
a	O
coverage	O
change	O
of	O
approximately	O
four	O
degrees	O
elevation	O
.	O
</s>
<s>
The	O
upper	O
beam	O
on	O
the	O
ASR-9	B-Algorithm
is	O
used	O
primarily	O
for	O
short	O
range	O
reception	O
,	O
while	O
the	O
lower	O
beam	O
was	O
mainly	O
used	O
for	O
transmitting	O
as	O
well	O
as	O
long	O
range	O
reception	O
.	O
</s>
<s>
A	O
combination	O
of	O
beam	O
displacement	O
,	O
as	O
well	O
as	O
a	O
sharp	O
underside	O
cut	O
off	O
,	O
gave	O
the	O
ASR-9	B-Algorithm
a	O
technological	O
advantage	O
when	O
compared	O
to	O
previously	O
installed	O
ASR	O
systems	O
;	O
the	O
radar	O
systems	O
before	O
the	O
ASR-9	B-Algorithm
had	O
not	O
been	O
able	O
to	O
reject	O
ground	O
clutter	O
when	O
transmitting	O
with	O
the	O
upper	O
beam	O
.	O
</s>
<s>
Building	O
-	O
Each	O
ASR-9	B-Algorithm
site	O
of	O
installation	O
received	O
a	O
prefabricated	O
metal	O
building	O
with	O
a	O
dedicated	O
generator	O
engine	O
room	O
.	O
</s>
<s>
Engine	O
Generator	O
-	O
The	O
equipment	O
used	O
on	O
the	O
ASR-9	B-Algorithm
is	O
50kW	O
generator	O
engine	O
,	O
as	O
well	O
as	O
the	O
associated	O
equipment	O
to	O
provide	O
emergency	O
electricity	O
in	O
the	O
case	O
of	O
a	O
power	O
outage	O
.	O
</s>
