<s>
An	O
organ-pipe	B-Algorithm
scanner	I-Algorithm
is	O
a	O
system	O
used	O
in	O
some	O
radar	B-Application
systems	I-Application
to	O
provide	O
scanning	O
in	O
azimuth	O
or	O
elevation	O
without	O
moving	O
the	O
antenna	O
.	O
</s>
<s>
The	O
system	O
was	O
found	O
in	O
a	O
number	O
of	O
1950s	O
and	O
60	O
's	O
era	O
radars	B-Application
,	O
notably	O
the	O
US	O
's	O
AN/FPS	B-Architecture
-50	I-Architecture
radar	B-Application
used	O
in	O
the	O
BMEWS	B-Architecture
network	O
,	O
and	O
the	O
High	O
Speed	O
Aerial	O
of	O
the	O
UK	O
's	O
RX12874	O
Passive	O
Detection	O
System	O
.	O
</s>
<s>
A	O
similar	O
concept	O
is	O
the	O
Foster	B-Algorithm
scanner	I-Algorithm
,	O
which	O
is	O
typically	O
found	O
on	O
lower-power	O
systems	O
like	O
counter-battery	O
radars	B-Application
.	O
</s>
