<s>
The	O
IEEE	O
K-band	B-Algorithm
is	O
a	O
portion	O
of	O
the	O
radio	B-Algorithm
spectrum	I-Algorithm
in	O
the	O
microwave	O
range	O
of	O
frequencies	O
from	O
18	O
to	O
27-Gigahertz	O
(	O
GHz	O
)	O
.	O
</s>
<s>
The	O
range	O
of	O
frequencies	O
in	O
the	O
center	O
of	O
the	O
K-band	B-Algorithm
between	O
18	O
-	O
and	O
26.5-GHz	O
is	O
absorbed	O
by	O
water	O
vapor	O
in	O
the	O
atmosphere	O
due	O
to	O
its	O
resonance	O
peak	O
at	O
22.24-GHz	O
,	O
.	O
</s>
<s>
For	O
this	O
reason	O
the	O
original	O
K-band	B-Algorithm
has	O
been	O
split	O
into	O
three	O
bands	O
,	O
Ka-band	O
,	O
K-band	B-Algorithm
,	O
and	O
Ku-band	B-Algorithm
as	O
detailed	O
below	O
.	O
</s>
<s>
Because	O
of	O
the	O
water	O
vapor	O
absorption	O
peak	O
in	O
the	O
center	O
of	O
the	O
band	O
,	O
the	O
IEEE	O
K-band	B-Algorithm
is	O
conventionally	O
divided	O
into	O
three	O
sub-bands	O
:	O
</s>
<s>
Ku-band	B-Algorithm
:	O
K-under	O
band	O
,	O
12	O
–	O
18-GHz	O
,	O
mainly	O
used	O
for	O
satellite	O
communications	O
,	O
direct-broadcast	O
satellite	O
television	O
,	O
terrestrial	O
microwave	O
communications	O
,	O
and	O
radar	B-Application
,	O
especially	O
police	O
traffic-speed	O
detectors	O
.	O
</s>
<s>
K-band	B-Algorithm
18	O
–	O
27-GHz	O
:	O
Due	O
to	O
the	O
22-GHz	O
water	O
vapor	O
absorption	O
line	O
this	O
band	O
has	O
high	O
atmospheric	O
attenuation	O
and	O
is	O
only	O
useful	O
for	O
short	O
range	O
applications	O
.	O
</s>
<s>
Ka-band	O
:	O
K-above	O
band	O
,	O
26.5	O
–	O
40-GHz	O
,	O
mainly	O
used	O
for	O
satellite	O
communications	O
,	O
radar	B-Application
and	O
experimental	O
communications	O
.	O
</s>
<s>
The	O
Radio	O
Regulations	O
of	O
the	O
International	O
Telecommunication	O
Union	O
(	O
ITU	O
)	O
allow	O
amateur	O
radio	O
and	O
amateur	O
satellite	O
operations	O
in	O
the	O
frequency	O
range	O
24.000-GHz	O
to	O
24.250-GHz	O
,	O
which	O
is	O
known	O
as	O
the	O
1.2-centimeter	B-Algorithm
band	I-Algorithm
.	O
</s>
<s>
It	O
is	O
also	O
referred	O
to	O
as	O
the	O
K-band	B-Algorithm
by	O
AMSAT	O
.	O
</s>
