Unlicensed National Information Infrastructure

The Unlicensed National Information Infrastructure (U-NII)^[1][2] radio band, as defined by the United States Federal Communications Commission, is part of the radio frequency spectrum used by WLAN devices and by many wireless ISPs.

As of March 2021, U-NII consists of eight ranges. U-NII 1 through 4 are for 5 GHz WLAN (802.11a and newer), and 5 through 8 are for 6 GHz WLAN (802.11ax) use. U-NII 2 is further divided into three subsections.

U-NII bands and FCC regs

Name	Aliases	Freq. Range (GHz)	Bandwidth (MHz)	Max Power (mW)	Max EIRP (mW)
U-NII-1	U-NII Low / U-NII Indoor	5.150–5.250	100	50	200
U-NII-2A	U-NII Mid	5.250–5.350	100	250	1,000
U-NII-2B		5.350–5.470	120	—	—
U-NII-2C	U-NII Worldwide / U-NII-2-Extended / U-NII-2e	5.470–5.725	255	250	1,000
U-NII-3	U-NII Upper	5.725-5.850	125	1,000	4,000
U-NII-4	DSRC/ITS	5.850–5.925	75	—	—
U-NII-5		5.925–6.425	500	—	—
U-NII-6		6.425–6.525	100	—	—
U-NII-7		6.525–6.875	350	—	—
U-NII-8		6.875–7.125	250	—	—

Wireless ISPs generally use 5.725–5.825 GHz.
In the USA licensed amateur radio operators are authorized 5.650–5.925 GHz by Part 97.303 of the FCC rules.

U-NII power limits are defined by the United States CFR Title 47 (Telecommunication), Part 15 - Radio Frequency Devices, Subpart E - Unlicensed National Information Infrastructure Devices, Paragraph 15.407 - General technical requirements.

Many other countries use similar bands for Wireless communication due to a shared IEEE standard. However, regulatory use in individual countries may differ.

The defunct European HiperLAN standard operates in same frequency band as the U-NII.

5 GHz (802.11a/h/j/n/ac/ax)

Except where noted, all information taken from Annex J of IEEE 802.11-2007 modified by amendments k, y and n. Because countries set their own regulations regarding specific uses and maximum power levels within these frequency ranges, it is recommended that local authorities are consulted as regulations may change at any time.

It operates over four ranges:

• U-NII Low (U-NII-1^[3]): 5.150–5.250 GHz. Originally limited to indoor use only. Regulations required use of an integrated antenna, with power limited to 50 mW.^[4] Rules changed in 2014 to permit outdoor operation, maximum fixed power 1 watt, maximum fixed EIRP 4 watts (+36 dBm) point-to-multipoint, 200 watts (+53 dBm) point-to-point. However, strict out-of-band emission rules limit practical point-to-point power to lower levels.
• U-NII Mid (U-NII-2A^[3]): 5.250–5.350 GHz. Both outdoor and indoor use, subject to Dynamic Frequency Selection (DFS, or radar avoidance). Regulations allow for a user-installable antenna.^[5] Power limited to 250 mW.^[4]
• U-NII-2B: 5.350–5.470 GHz. Currently 120 MHz of spectrum not allocated by the FCC for unlicensed use.
• U-NII Worldwide (U-NII-2C / U-NII-2e): 5.470–5.725 GHz. Both outdoor and indoor use, subject to Dynamic Frequency Selection (DFS, or radar avoidance).^[5] Power limited to 250 mW.^[4] This spectrum was added by the FCC in 2003 to "align the frequency bands used by U-NII devices in the United States with bands in other parts of the world".^[5] The FCC currently has an interim limitation on operations on channels which overlap the 5600–5650 MHz band.^[6]
• U-NII Upper (U-NII-3^[7]): 5.725–5.850 GHz. Sometimes referred to as U-NII / ISM due to overlap with the ISM band. Regulations allow for a user-installable antenna. Power limited to 1W in the United States^[4] and 25mW in European Union.^[8]
• DSRC/ITS (U-NII-4^[9]): 5.850–5.925 GHz. At present U-NII-4 spectrum is being considered by the FCC for unlicensed use. U-NII-4 is presently only usable for Dedicated Short Range Communications Service (DSRC) and licensed amateur radio operators.

In 2007, the FCC began requiring that devices operating in channels 52, 56, 60 and 64 must have Dynamic Frequency Selection (DFS) capabilities. This is to avoid communicating in the same frequency range as some radar. In 2014, the FCC issued new rules^[10] for all devices due to interference with government weather radar systems. Fines and equipment seizure were listed as punishment for non-compliance.

Band	Channel	Frequency (MHz)	United States	Europe	Japan		Singapore	China	Israel	Korea	Turkey	India		United Kingdom
			40/20 MHz[11]	40/20 MHz	40/20 MHz[12]	10 MHz	20 MHz	20 MHz	20 MHz[13]	20 MHz[14]	20 MHz	40/20 MHz	5/10 MHz[15]	80/40/20 MHz[16]
	183	4915	No	No	No	Yes	No	No	No	No	No	No	Yes	No
	184	4920	No	No	Yes	Yes	No	No	No	No	No	Yes	Yes	No
	185	4925	No	No	No	Yes	No	No	No	No	No	No	Yes	No
	187	4935	No	No	No	Yes	No	No	No	No	No	No	Yes	No
	188	4940	No	No	Yes	Yes	No	No	No	No	No	Yes	Yes	No
	189	4945	No	No	No	Yes	No	No	No	No	No	No	Yes	No
	192	4960	No	No	Yes	No	No	No	No	No	No	Yes	Yes	No
	196	4980	No	No	Yes	No	No	No	No	No	No	Yes	Yes	No
	7	5035	No	No	No	Yes	No	No	No	No	No	No	No	No
	8	5040	No	No	No	Yes	No	No	No	No	No	No	No	No
	9	5045	No	No	No	Yes	No	No	No	No	No	No	No	No
	11	5055	No	No	No	Yes	No	No	No	No	No	No	No	No
	12	5060	No	No	No	No	No	No	No	No	No	No	No	No
	16	5080	No	No	No	No	No	No	No	No	No	No	No	No
U-NII-1	34	5170	No	No	No	No	No	No	Yes	Yes	Yes	Yes	Yes	No
	36	5180	Yes	Yes	Yes	No	Yes	No	Yes	Yes	Yes	Yes	Yes	Yes
	38	5190	No	No	No	No	No	No	Yes	Yes	Yes	Yes	Yes	No
	40	5200	Yes	Yes	Yes	No	Yes	No	Yes	Yes	Yes	Yes	Yes	Yes
	42	5210	No	No	No	No	No	No	Yes	Yes	Yes	Yes	Yes	No
	44	5220	Yes	Yes	Yes	No	Yes	No	Yes	Yes	Yes	Yes	Yes	Yes
	46	5230	No	No	No	No	No	No	Yes	Yes	Yes	Yes	Yes	No
	48	5240	Yes	Yes	Yes	No	No	No	Yes	Yes	Yes	Yes	Yes	Yes
U-NII-2A	52	5260	Yes	Yes	Yes	No	No	No	Yes	No	No	No	No	Yes
	56	5280	Yes	Yes	Yes	No	No	No	Yes	Yes	Yes	Yes	Yes	Yes
	60	5300	Yes	Yes	Yes	No	No	No	Yes	Yes	Yes	Yes	Yes	Yes
	64	5320	Yes	Yes	Yes	No	No	No	Yes	Yes	Yes	Yes	Yes	Yes
U-NII-2B		5350–5470	No	Un­known										No
U-NII-2C	100	5500	Yes[17]	Yes	Yes	No	No	No	No	Yes	No	Yes	Yes	Yes
	104	5520	Yes[17]	Yes	Yes	No	No	No	No	Yes	No	Yes	Yes	Yes
	108	5540	Yes[17]	Yes	Yes	No	No	No	No	Yes	No	Yes	Yes	Yes
	112	5560	Yes[17]	Yes	Yes	No	No	No	No	Yes	No	Yes	Yes	Yes
	116	5580	Yes[17]	Yes	Yes	No	No	No	No	Yes	No	Yes	Yes	Yes
	120	5600	No[18]	Yes	Yes	No	No	No	No	Yes	No	Yes	Yes	Yes
	124	5620	No	Yes	Yes	No	No	No	No	Yes	No	Yes	Yes	Yes
	128	5640	No	Yes	Yes	No	No	No	No	Yes	No	Yes	Yes	Yes
	132	5660	Yes[17]	Yes	Yes	No	No	No	No	No	No	No	Yes	Yes
	136	5680	Yes[17]	Yes	Yes	No	No	No	No	No	No	Yes	Yes	Yes
	140	5700	Yes[17]	Yes	Yes	No	No	No	No	No	No	No	Yes	Yes
U-NII-3	149	5745	Yes	Yes[8]	No	No	Yes	Yes	No	Yes	Yes	Yes	Yes	Yes
	153	5765	Yes	Yes[8]	No	No	Yes	Yes	No	Yes	Yes	Yes	Yes	Yes
	157	5785	Yes	Yes[8]	No	No	Yes	Yes	No	Yes	Yes	Yes	Yes	Yes
	161	5805	Yes	Yes[8]	No	No	Yes	Yes	No	Yes	Yes	Yes	Yes	Yes
	165	5825	Yes	Yes[8]	No	No	Yes	Yes	No	Yes	Yes	Yes	Yes	Yes
U-NII-4[19]	169	5845	No	Un­known								No	Yes	No
	173	5865	No	Un­known								No	Yes	No
	177	5885	No	Un­known								No	Yes	No
	181	5905	No	Un­known								No	Yes	No
	185	5925 (proposed expansion)	No	Un­known								No	Yes	No
Band	Channel	Frequency (MHz)	40/20 MHz	40/20 MHz	40/20 MHz	10 MHz	20 MHz	20 MHz	20 MHz	20 MHz	20 MHz	40/20 MHz	5/10 MHz	80/40/20 MHz
			United States	Europe	Japan		Singapore	China	Israel	Korea	Turkey	India		United Kingdom

See also

• List of WLAN channels § 5 GHz (802.11a/h/j/n/ac/ax)
• Part 15 (FCC rules)
• ISM band
• 802.11

References

1. "15.07.2005, Heise: 5 GHz WLAN to be available all over Europe" www.heise.de Archived 2005-08-07 at the Wayback Machine
2. ""Cisco: Glossary" www.cisco.com".
3. ""Dynamic Frequency Selection for 5 GHz WLAN in the US and Canada" www.cisco.com".
4. "FCC 15.407 as of October 1, 2014 - hallikainen.com". www.hallikainen.com.
5. "FCC-03-287A1.doc" (PDF).
6. ""15E, Dynamic Frequency Selection, DFS, DFS Approval" fcc.gov".
7. "What's New With Unlicensed National Information Infrastructure (U-NII)" (PDF).
8. "Tableau national de répartition des bandes de fréquences" (PDF). EU/ANFR. January 10, 2019.
9. "Driving Wi-Fi Ahead: the Upper 5 GHz Band". 23 February 2015.
10. "5 GHz Unlicensed Spectrum (UNII)". 12 December 2015.
11. FCC 15.407 as of August 8, 2008 – hallikainen.com Archived July 24, 2011, at the Wayback Machine
12. "802.11-2007 Japan MIC Released the new 5 GHz band (W56)" (PDF). Bureau Veritas — ADT. Archived from the original (PDF) on 2007-07-10. Retrieved 2008-02-23.
13. Israel: צו הטלגרף האלחוטי (אי תחולת הפקודה) (מס' 2), התשס"ו – 2005 (PDF) (in Hebrew).
14. Korea Frequency Distribution Table 2008.12.31 (in Korean)
15. India frequency allocation table
16. Ofcom Decision to make Wireless Telegraphy Exemption Regulations 2017
17. "Publication Number: 443999 Rule Parts: 15E". FCC. October 5, 2009. Devices must be professionally installed when operating in the 5470 – 5725 MHz band
18. "Elimination of interference to Terminal Doppler Weather Radar" (PDF). FCC. July 27, 2010.
19. "(see page 9) Sharing the 5.9 GHz Band Between Unlicensed Devices and DSRC" (PDF).

External links

• In the USA, CFR Title 47 Part 15 (revised in 2005) describes the regulation of the U-NII bands.
• The FCC's U-NII regulations for 5 GHz wireless operation in the USA.
• RadioElectronics' article on Wi-Fi / WLAN Channels, Frequencies, Bands & Bandwidths
• Air802's article with tables of data on FCC Rules and Regulations which specifies frequencies and channels.
• Government of India NATIONAL FREQUENCY ALLOCATION PLAN-2011
• Government of India NATIONAL FREQUENCY ALLOCATE TABLE (Latest)