<s>
The	O
Unlicensed	B-Algorithm
National	I-Algorithm
Information	I-Algorithm
Infrastructure	I-Algorithm
(	O
U-NII	B-Algorithm
)	O
radio	B-Algorithm
band	I-Algorithm
,	O
as	O
defined	O
by	O
the	O
United	O
States	O
Federal	O
Communications	O
Commission	O
,	O
is	O
part	O
of	O
the	O
radio	O
frequency	O
spectrum	O
used	O
by	O
WLAN	B-Architecture
devices	O
and	O
by	O
many	O
wireless	B-General_Concept
ISPs	I-General_Concept
.	O
</s>
<s>
As	O
of	O
March	O
2021	O
,	O
U-NII	B-Algorithm
consists	O
of	O
eight	O
ranges	O
.	O
</s>
<s>
U-NII	B-Algorithm
1	O
through	O
4	O
are	O
for	O
5	O
GHz	O
WLAN	B-Architecture
(	O
802.11a	O
and	O
newer	O
)	O
,	O
and	O
5	O
through	O
8	O
are	O
for	O
6	O
GHz	O
WLAN	B-Architecture
(	O
802.11ax	O
)	O
use	O
.	O
</s>
<s>
U-NII	B-Algorithm
2	O
is	O
further	O
divided	O
into	O
three	O
subsections	O
.	O
</s>
<s>
+	O
U-NII	B-Algorithm
bands	I-Algorithm
and	O
FCC	O
regs	O
Name	O
Aliases	O
Freq	O
.	O
</s>
<s>
Wireless	B-General_Concept
ISPs	I-General_Concept
generally	O
use	O
5.725	O
–	O
5.825GHz	O
.	O
</s>
<s>
U-NII	B-Algorithm
power	O
limits	O
are	O
defined	O
by	O
the	O
United	O
States	O
CFR	O
Title	O
47	O
(	O
Telecommunication	O
)	O
,	O
Part	O
15	O
-	O
Radio	O
Frequency	O
Devices	O
,	O
Subpart	O
E	O
-	O
Unlicensed	B-Algorithm
National	I-Algorithm
Information	I-Algorithm
Infrastructure	I-Algorithm
Devices	O
,	O
Paragraph	O
15.407	O
-	O
General	O
technical	O
requirements	O
.	O
</s>
<s>
The	O
defunct	O
European	O
HiperLAN	O
standard	O
operates	O
in	O
same	O
frequency	O
band	O
as	O
the	O
U-NII	B-Algorithm
.	O
</s>
<s>
U-NII	B-Algorithm
Low	O
(	O
U-NII-1	O
)	O
:	O
5.150	O
–	O
5.250GHz	O
.	O
</s>
<s>
U-NII	B-Algorithm
Mid	O
(	O
U-NII-2A	O
)	O
:	O
5.250	O
–	O
5.350GHz	O
.	O
</s>
<s>
Both	O
outdoor	O
and	O
indoor	O
use	O
,	O
subject	O
to	O
Dynamic	B-Protocol
Frequency	I-Protocol
Selection	I-Protocol
(	O
DFS	O
,	O
or	O
radar	B-Application
avoidance	O
)	O
.	O
</s>
<s>
U-NII-2B	O
:	O
5.350	O
–	O
5.470GHz	O
.	O
</s>
<s>
U-NII	B-Algorithm
Worldwide	O
(	O
U-NII-2C	O
/	O
U-NII-2e	O
)	O
:	O
5.470	O
–	O
5.725GHz	O
.	O
</s>
<s>
Both	O
outdoor	O
and	O
indoor	O
use	O
,	O
subject	O
to	O
Dynamic	B-Protocol
Frequency	I-Protocol
Selection	I-Protocol
(	O
DFS	O
,	O
or	O
radar	B-Application
avoidance	O
)	O
.	O
</s>
<s>
This	O
spectrum	O
was	O
added	O
by	O
the	O
FCC	O
in	O
2003	O
to	O
"	O
align	O
the	O
frequency	O
bands	O
used	O
by	O
U-NII	B-Algorithm
devices	O
in	O
the	O
United	O
States	O
with	O
bands	O
in	O
other	O
parts	O
of	O
the	O
world	O
"	O
.	O
</s>
<s>
U-NII	B-Algorithm
Upper	O
(	O
U-NII-3	O
)	O
:	O
5.725	O
–	O
5.850GHz	O
.	O
</s>
<s>
Sometimes	O
referred	O
to	O
as	O
U-NII	B-Algorithm
/	O
ISM	O
due	O
to	O
overlap	O
with	O
the	O
ISM	B-Algorithm
band	I-Algorithm
.	O
</s>
<s>
DSRC/ITS	O
(	O
U-NII-4	O
)	O
:	O
5.850	O
–	O
5.925GHz	O
.	O
</s>
<s>
At	O
present	O
U-NII-4	O
spectrum	O
is	O
being	O
considered	O
by	O
the	O
FCC	O
for	O
unlicensed	O
use	O
.	O
</s>
<s>
U-NII-4	O
is	O
presently	O
only	O
usable	O
for	O
Dedicated	O
Short	O
Range	O
Communications	O
Service	O
(	O
DSRC	O
)	O
and	O
licensed	O
amateur	O
radio	O
operators	O
.	O
</s>
<s>
In	O
2007	O
,	O
the	O
FCC	O
began	O
requiring	O
that	O
devices	O
operating	O
in	O
channels	O
52	O
,	O
56	O
,	O
60	O
and	O
64	O
must	O
have	O
Dynamic	B-Protocol
Frequency	I-Protocol
Selection	I-Protocol
(	O
DFS	O
)	O
capabilities	O
.	O
</s>
<s>
This	O
is	O
to	O
avoid	O
communicating	O
in	O
the	O
same	O
frequency	O
range	O
as	O
some	O
radar	B-Application
.	O
</s>
<s>
In	O
2014	O
,	O
the	O
FCC	O
issued	O
new	O
rules	O
for	O
all	O
devices	O
due	O
to	O
interference	O
with	O
government	O
weather	O
radar	B-Application
systems	I-Application
.	O
</s>
