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Wi-Fi 6

From Wikipedia, the free encyclopedia
(Redirected fromWi-Fi 6E)
Wireless networking standard
Wi-Fi 6
Icon used by theWi-Fi Alliance for Wi-Fi 6
Introduced1 September 2020; 5 years ago (2020-09-01)
Compatible hardwarePersonal computers,gaming consoles,smart devices,televisions,printers,security cameras
Wi-Fi generations
Gen.[1]IEEE
standard		Adopt.Link rate
(Mbit/s)		RF (GHz)
2.456
—802.1119971–2Yes
—802.11b19991–11Yes
—802.11a6–54Yes
—802.11g2003Yes
Wi-Fi 4802.11n20096.5–600YesYes
Wi-Fi 5802.11ac20136.5–6,933[a]Yes
Wi-Fi 6802.11ax20210.4–9,608YesYes
Wi-Fi 6EYesYesYes
Wi-Fi 7802.11be20240.4–23,059YesYesYes
Wi-Fi 8[2][3]802.11bnTBAYesYesYes

IEEE 802.11ax-2021[4] or802.11ax, is anIEEE standard from theWi-Fi Alliance, for wireless networks (WLANs). The standard is marketed asWi-Fi 6.[5] It operates in the 2.4 GHz and 5 GHz bands,[6] with an extended version,Wi-Fi 6E, that adds the6 GHz band.[7] It is an upgrade from Wi-Fi 5 (IEEE 802.11ac), with improvements for better performance in crowded places. Wi-Fi 6 covers frequencies inlicense-exempt ISM bands, including the commonly used 2.4 GHz and 5 GHz, as well as the broader 6 GHz band (for WiFi 6E).[8]

This standard aims to boostthroughput[b] in crowded places like offices and malls. Though the nominal data rate is only 37%[9] higher than that of 802.11ac, the throughput increases by at least four times,[10] making it more efficient and reducing latency by 75%.[11] The quintupling of overall throughput is made possible by higherspectral efficiency.

802.11ax Wi-Fi has a main feature calledOFDMA, similar to howcellular common-carrier networks work.[9] This brings better spectrum use, improved power control to avoid interference, and enhancements like 1024‑QAM,MIMO andMU-MIMO for faster speeds. There are also reliability improvements such as lower power consumption and security protocols likeTarget Wake Time andWPA3.

The 802.11ax standard was approved on September 1, 2020, with Draft 8 getting 95% approval. Subsequently, on February 1, 2021, the standard received official endorsement from the IEEE Standards Board.[12]

Rate set

[edit]
Modulation and coding schemes
MCS
index
[i]		Modulation
type		Coding
rate		Data rate (Mbit/s)[ii]
Channel width (MHz)
204080160
Guard Interval (μs)
1.60.81.60.81.60.81.60.8
0BPSK1/288.61617.23436.06872
1QPSK1/21617.23334.46872.1136144
2QPSK3/42425.84951.6102108.1204216
316-QAM1/23334.46568.8136144.1272288
416-QAM3/44951.698103.2204216.2408432
564-QAM2/36568.8130137.6272288.2544576
664-QAM3/47377.4146154.9306324.4613649
764-QAM5/68186.0163172.1340360.3681721
8256-QAM3/498103.2195206.5408432.4817865
9256-QAM5/6108114.7217229.4453480.4907961
101024-QAM3/4122129.0244258.1510540.410211081
111024-QAM5/6135143.4271286.8567600.511341201

Notes

  1. ^MCS 9 is not applicable to all combinations of channel width and spatial stream count.
  2. ^Per spatial stream.

OFDMA

[edit]

In 802.11ac (802.11's previous amendment),multi-user MIMO was introduced, which is aspatial multiplexing technique. MU-MIMO allows the access point to form beams towards eachclient, while transmitting information simultaneously. By doing so, the interference between clients is reduced, and the overall throughput is increased, since multiple clients can receive data simultaneously.

With 802.11ax, a similar multiplexing is introduced in thefrequency-division multiplexing:OFDMA. With OFDMA, multiple clients are assigned to differentResource Units in the available spectrum. By doing so, an 80 MHz channel can be split into multiple Resource Units, so that multiple clients receive different types of data over the same spectrum, simultaneously.

To supportOFDMA, 802.11ax needs four times as many subcarriers as 802.11ac. Specifically, for 20, 40, 80, and 160 MHz channels, the 802.11ac standard has, respectively, 64, 128, 256 and 512 subcarriers while the 802.11ax standard has 256, 512, 1024, and 2048 subcarriers. Since the available bandwidths have not changed and the number of subcarriers increases by a factor of four, thesubcarrier spacing is reduced by the same factor. This introduces OFDM symbols that are four times longer: in 802.11ac, an OFDM symbol takes 3.2 microseconds to transmit. In 802.11ax, it takes 12.8 microseconds (both withoutguard intervals).

Technical improvements

[edit]

The 802.11ax amendment brings several key improvements over802.11ac. While 802.11ac only uses the 5 GHz band, which is a bit over 700 MHzwide, 802.11ax also allows the use of the 2.4 GHz band of some earlier protocols, less than 100 MHz wide, and the larger 6 GHz band, about 1200 MHz wide.[13]Wi-Fi 6E adds toWi‑Fi 6 the use of the 6 GHz band and, thereby, channels that are160 MHz wide without the restrictions ofDynamic Frequency Selection that apply to all160 MHz channels in the5 GHz band.[14] The number and selection of channels available depends on the country a given Wi-Fi 6 network operates in.[15] To meet the goal of supporting dense 802.11 deployments, the following features have been approved.

Feature802.11ac802.11axComment
OFDMAnot availableCentrally controlled medium access with dynamic assign­ment of 26, 52, 106, 242(?), 484(?), or 996(?) tones per station. Each tone consists of a single subcarrier of 78.125 kHz bandwidth. Therefore, a singleOFDMA transmission is between 2.03125 MHz and ca. 80 MHz wide.OFDMA segregates the spectrum in time-frequencyresource units (RUs). A central coordinating entity (the AP in 802.11ax) assigns RUs for reception or transmission to associated stations. Through the central scheduling of the RUs, contention overhead can be avoided, which increases efficiency in scenarios of dense deployments.
Multi-user MIMO(MU-MIMO)Available inDownlink directionAvailable in Downlink andUplink directionWith downlink MU-MIMO an AP may transmit concurrently with multiple stations, and with uplink MU-MIMO an AP may simultaneously receive from multiple stations. WhereasOFDMA separates receivers to differentRUs, with MU-MIMO the devices are separated into different spatial streams. In 802.11ax, MU-MIMO and OFDMA can be used simultaneously. To enable uplink MU transmissions, the AP transmits a new control frame (Trigger) which contains scheduling information (RU allocations for stations, and the modulation and coding scheme (MCS) that shall be used for each station). Furthermore, a Trigger also provides synchronization for an uplink transmission, since the transmission startsSIFS after the end of a Trigger.
Trigger-based Random Accessnot availableAllows performing UL OFDMA transmissions by stations which are not allocated RUs directlyIn a Trigger frame, the AP specifies scheduling information about subsequent UL MU transmission. However, several RUs can be assigned for random access. Stations which are not assigned RUs directly can perform transmissions within RUs assigned for random access. To reduce collision probability (i.e. situation when two or more stations select the sameRU for transmission), the 802.11ax amendment specifies a special OFDMA back-off procedure. Random access is favorable for transmitting buffer status reports when the AP has no information about pending UL traffic at a station.
Spatial frequency reusenot availableColoring enables devices to differentiate transmissions in their own network from trans­missions in neighboring net­works. Adaptive power and sensitivity thresholds allow dynamically adjusting transmit power and signal detection threshold to increase spatial reuse.Without spatial reuse capabilities devices refuse transmitting concurrently with transmissions in neighboring networks. With basic service set coloring (BSS coloring), a wireless transmission is marked at its very beginning, helping surrounding devices to decide if a simultaneous use of the wireless medium is permissible. A station is allowed to consider the wireless medium idle and start a new transmission even if the detected signal level from a neighboring network exceeds the legacy signal detection threshold, provided that the transmit power for the new transmission is appropriately decreased.
NAVSingle NAVDual NAVsIn dense deployment scenarios, theNAV value set by a frame from one network may be easily reset by a frame from another network, which leads to misbehavior and collisions. To avoid this, each 802.11ax station will maintain two separate NAVs: One NAV is modified by frames from a network the station is associated with, while the other NAV is modified by frames from overlapping networks.
Target Wake Time (TWT)not availableTWT reduces power consumption and medium access contention.TWT is a concept developed in802.11ah. It allows devices to wake up at times other than the periodic beacon transmission time. Furthermore, the AP may group devices with various TWT periods, thereby reducing the number of devices contending simultaneously for the wireless medium.
FragmentationStaticDynamicWith static fragmentation, all fragments of a data packet are of equal size, except for the last fragment. With dynamic fragmentation, a device may fill available RUs of other opportunities to transmit up to the available maximum duration. Thus, dynamic fragmentation helps reduce overhead.
Guard interval duration0.4 or 0.8 μs0.8, 1.6 or 3.2 μsExtended guard interval durations allow for better protection against signal delay spread as it occurs in outdoor environments.
Symbol duration3.2 μs12.8 μsSince the subcarrier spacing is reduced by a factor of four, the OFDM symbol duration is increased by a factor of four as well. Extended symbol durations allow for increased efficiency.[16]
Frequency bands5 GHz only2.4 and 5 GHz802.11ac falls back to 802.11n for the 2.4 GHz band.

Comparison

[edit]
802.11 network standards
Frequency
range,
or type		PHYProtocolRelease
date[17]		Freq­uency bandChannel widthStream
data rate[18]		Max.
MIMO streams		ModulationApprox. range
In­doorOut­door
(GHz)(MHz)(Mbit/s)
1–7 GHzDSSS[19],FHSS[A]802.11-1997June 19972.4221, 2—DSSS,FHSS[A]20 m (66 ft)100 m (330 ft)
HR/DSSS[19]802.11bSeptember 19992.4221, 2, 5.5, 11—CCK, DSSS35 m (115 ft)140 m (460 ft)
OFDM802.11aSeptember 199955, 10, 206, 9, 12, 18, 24, 36, 48, 54
(for 20 MHz bandwidth,
divide by 2 and 4 for 10 and 5 MHz)		—OFDM35 m (115 ft)120 m (390 ft)
802.11jNovember 20044.9, 5.0
[B][20]		??
802.11yNovember 20083.7[C]?5,000 m (16,000 ft)[C]
802.11pJuly 20105.9200 m1,000 m (3,300 ft)[21]
802.11bdDecember 20225.9, 60500 m1,000 m (3,300 ft)
ERP-OFDM[22]802.11gJune 20032.438 m (125 ft)140 m (460 ft)
HT-OFDM[23]802.11n
(Wi-Fi 4)		October 20092.4, 520Up to 288.8[D]4MIMO-OFDM
(64-QAM)		70 m (230 ft)250 m (820 ft)[24]
40Up to 600[D]
VHT-OFDM[23]802.11ac
(Wi-Fi 5)		December 2013520Up to 693[D]8DL
MU-MIMOOFDM
(256-QAM)		35 m (115 ft)[25]?
40Up to 1,600[D]
80Up to 3,467[D]
160Up to 6,933[D]
HE-OFDMA802.11ax
(Wi-Fi 6,
Wi-Fi 6E)		May 20212.4, 5, 620Up to 1,147[E]8UL/DL
MU-MIMOOFDMA
(1024-QAM)		30 m (98 ft)120 m (390 ft)[F]
40Up to 2,294[E]
80Up to 5,500[E]
80+80Up to 11,000[E]
EHT-OFDMA802.11be
(Wi-Fi 7)		Sep 20242.4, 5, 680Up to 5,764[E]8UL/DL
MU-MIMOOFDMA
(4096-QAM)		30 m (98 ft)120 m (390 ft)[F]
160
(80+80)		Up to 11,500[E]
240
(160+80)		Up to 14,282[E]
320
(160+160)		Up to 23,059[E]
UHR802.11bn
(Wi-Fi 8)		May 2028
(est.)		2.4, 5, 6320Up to
23,059
8Multi-link
MU-MIMOOFDM
(4096-QAM)		??
WUR[G]802.11baOctober 20212.4, 54, 200.0625, 0.25
(62.5 kbit/s, 250 kbit/s)		—OOK (multi-carrier OOK)??
mmWave
(WiGig)		DMG[26]802.11adDecember 2012602,160
(2.16 GHz)		Up to 8,085[27]
(8 Gbit/s)		—OFDM,[A] single carrier, low-power single carrier[A]3.3 m (11 ft)[28]?
802.11ajApril 201860[H]1,080[29]Up to 3,754
(3.75 Gbit/s)		—single carrier, low-power single carrier[A]??
CMMG802.11ajApril 201845[H]540,
1,080		Up to 15,015[30]
(15 Gbit/s)		4[31]OFDM, single carrier??
EDMG[32]802.11ayJuly 202160Up to 8,640
(8.64 GHz)		Up to 303,336[33]
(303 Gbit/s)		8OFDM, single carrier10 m (33 ft)100 m (328 ft)
Sub 1 GHz (IoT)TVHT[34]802.11afFebruary 20140.054–
0.79		6, 7, 8Up to 568.9[35]4MIMO-OFDM??
S1G[34]802.11ahMay 20170.7, 0.8,
0.9		1–16Up to 8.67[36]
(@2 MHz)		4??
Light
(Li-Fi)		LC
(VLC/OWC)		802.11bbNovember 2023800–1000 nm20Up to 9.6 Gbit/s—O-OFDM??
IR[A]
(IrDA)		802.11-1997June 1997850–900 nm?1, 2—PPM[A]??
802.11 Standard rollups
 802.11-2007 (802.11ma)March 20072.4, 5Up to 54DSSS,OFDM
802.11-2012 (802.11mb)March 20122.4, 5Up to 150[D]DSSS,OFDM
802.11-2016 (802.11mc)December 20162.4, 5, 60Up to 866.7 or 6,757[D]DSSS,OFDM
802.11-2020 (802.11md)December 20202.4, 5, 60Up to 866.7 or 6,757[D]DSSS,OFDM
802.11-2024 (802.11me)September 20242.4, 5, 6, 60Up to 9,608 or 303,336DSSS,OFDM
  1. ^abcdefgThis is obsolete, and support for this might be subject to removal in a future revision of the standard
  2. ^For Japanese regulation.
  3. ^abIEEE 802.11y-2008 extended operation of 802.11a to the licensed 3.7 GHz band. Increased power limits allow a range up to 5,000 m. As of 2009[update], it is only being licensed in the United States by theFCC.
  4. ^abcdefghiBased on shortguard interval; standard guard interval is ~10% slower. Rates vary widely based on distance, obstructions, and interference.
  5. ^abcdefghFor single-user cases only, based on defaultguard interval which is 0.8 microseconds. Since multi-user viaOFDMA has become available for 802.11ax, these may decrease. Also, these theoretical values depend on the link distance, whether the link is line-of-sight or not, interferences and themulti-path components in the environment.
  6. ^abThe defaultguard interval is 0.8 microseconds. However, 802.11ax extended the maximum availableguard interval to 3.2 microseconds, in order to support Outdoor communications, where the maximum possible propagation delay is larger compared to Indoor environments.
  7. ^Wake-up Radio (WUR) Operation.
  8. ^abFor Chinese regulation.

Notes

[edit]
  1. ^802.11ac only specifies operation in the 5 GHz band. Operation in the 2.4 GHz band is specified by 802.11n.
  2. ^Throughput-per-area, as defined byIEEE, is the ratio of the total network throughput to the network area.[9]

References

[edit]
  1. ^"The Evolution of Wi-Fi Technology and Standards".IEEE. 2023-05-16. Retrieved2025-08-07.
  2. ^Karamyshev, Anton; Levitsky, Ilya; Bankov, Dmitry; Khorov, Evgeny (2025-10-06)."A Tutorial on Wi-Fi 8: The Journey to Ultra High Reliability".Problems of Information Transmission.61 (2).doi:10.1134/S003294602502005X. Retrieved2025-11-07.
  3. ^Giordano, Lorenzo; Geraci, Giovanni; Carrascosa, Marc; Bellalta, Boris (November 21, 2023). "What Will Wi-Fi 8 Be? A Primer on IEEE 802.11bn Ultra High Reliability".IEEE Communications Magazine.62 (8): 126.arXiv:2303.10442.Bibcode:2024IComM..62h.126G.doi:10.1109/MCOM.001.2300728.
  4. ^"IEEE 802.11ax-2021".IEEE Standards Association. Archived fromthe original on 2022-05-22. Retrieved2025-09-17.
  5. ^"Wi-Fi® (MAC/PHY)".Wi-Fi Alliance. Retrieved2025-09-17.
  6. ^"Generational Wi-Fi User Guide"(PDF).Wi-Fi Alliance. October 2018. Retrieved22 March 2021.
  7. ^"Wi-Fi 6E expands Wi-Fi into 6 GHz"(PDF).Wi-Fi Alliance. January 2021. Retrieved22 March 2021.
  8. ^"FCC Opens 6 GHz Band to Wi-Fi and Other Unlicensed Uses".www.fcc.gov. 24 April 2020. Retrieved23 March 2021.
  9. ^abcKhorov, Evgeny; Kiryanov, Anton; Lyakhov, Andrey; Bianchi, Giuseppe (2019)."A Tutorial on IEEE 802.11ax High Efficiency WLANs".IEEE Communications Surveys & Tutorials.21 (1):197–216.doi:10.1109/COMST.2018.2871099.
  10. ^Aboul-Magd, Osama (17 March 2014)."802.11 HEW SG Proposed PAR"(DOCX).IEEE.Archived from the original on 7 April 2014. Retrieved22 March 2021.
  11. ^Goodwins, Rupert (3 October 2018)."Next-generation 802.11ax wi-fi: Dense, fast, delayed".ZDNet. Retrieved23 March 2021.
  12. ^"IEEE 802.11, The Working Group Setting the Standards for Wireless LANs".www.ieee802.org. Retrieved2022-01-07.
  13. ^Aboul-Magd, Osama (2014-01-24)."P802.11ax"(PDF). IEEE-SA.Archived(PDF) from the original on 2014-10-10. Retrieved2017-01-14.2 page PDF download
  14. ^"Wi-Fi CERTIFIED 6 | Wi-Fi Alliance".
  15. ^"Wi-Fi 6E and 6 GHz Update"(PDF).www.wi-fi.org. 2021-03-11.
  16. ^Porat, Ron; Fischer, Matthew; Venkateswaran, Sriram; et al. (2015-01-12)."Payload Symbol Size for 11ax". IEEE P802.11. Retrieved2017-01-14.
  17. ^"Official IEEE 802.11 working group project timelines". January 26, 2017. Retrieved2017-02-12.
  18. ^"Wi-Fi CERTIFIED n: Longer-Range, Faster-Throughput, Multimedia-Grade Wi-Fi Networks"(PDF).Wi-Fi Alliance. September 2009.
  19. ^abBanerji, Sourangsu; Chowdhury, Rahul Singha (2013). "On IEEE 802.11: Wireless LAN Technology".arXiv:1307.2661 [cs.NI].
  20. ^"The complete family of wireless LAN standards: 802.11 a, b, g, j, n"(PDF).
  21. ^The Physical Layer of the IEEE 802.11p WAVE Communication Standard: The Specifications and Challenges(PDF). World Congress on Engineering and Computer Science. 2014.
  22. ^IEEE Standard for Information Technology- Telecommunications and Information Exchange Between Systems- Local and Metropolitan Area Networks- Specific Requirements Part II: Wireless LAN Medium Access Control (MAC) and Physical Layer (PHY) Specifications.doi:10.1109/ieeestd.2003.94282.ISBN 0-7381-3701-4.
  23. ^ab"Wi-Fi Capacity Analysis for 802.11ac and 802.11n: Theory & Practice"(PDF).
  24. ^Belanger, Phil; Biba, Ken (2007-05-31)."802.11n Delivers Better Range".Wi-Fi Planet. Archived fromthe original on 2008-11-24.
  25. ^"IEEE 802.11ac: What Does it Mean for Test?"(PDF).LitePoint. October 2013. Archived fromthe original(PDF) on 2014-08-16.
  26. ^"IEEE Standard for Information Technology".IEEE STD 802.11aj-2018. April 2018.doi:10.1109/IEEESTD.2018.8345727.ISBN 978-1-5044-4633-4.
  27. ^"802.11ad – WLAN at 60 GHz: A Technology Introduction"(PDF). Rohde & Schwarz GmbH. November 21, 2013. p. 14.
  28. ^"Connect802 – 802.11ac Discussion".www.connect802.com.
  29. ^"Understanding IEEE 802.11ad Physical Layer and Measurement Challenges"(PDF).
  30. ^"802.11aj Press Release".
  31. ^Hong, Wei; He, Shiwen; Wang, Haiming; Yang, Guangqi; Huang, Yongming; Chen, Jixing; Zhou, Jianyi; Zhu, Xiaowei; Zhang, Nianzhu; Zhai, Jianfeng; Yang, Luxi; Jiang, Zhihao; Yu, Chao (2018)."An Overview of China Millimeter-Wave Multiple Gigabit Wireless Local Area Network System".IEICE Transactions on Communications. E101.B (2):262–276.Bibcode:2018IEITC.101..262H.doi:10.1587/transcom.2017ISI0004.
  32. ^"IEEE 802.11ay: 1st real standard for Broadband Wireless Access (BWA) via mmWave – Technology Blog".techblog.comsoc.org.
  33. ^"P802.11 Wireless LANs". IEEE. pp. 2, 3. Archived fromthe original on 2017-12-06. RetrievedDec 6, 2017.
  34. ^ab"802.11 Alternate PHYs A whitepaper by Ayman Mukaddam"(PDF).
  35. ^"TGaf PHY proposal". IEEE P802.11. 2012-07-10. Retrieved2013-12-29.
  36. ^Sun, Weiping; Choi, Munhwan; Choi, Sunghyun (July 2013)."IEEE 802.11ah: A Long Range 802.11 WLAN at Sub 1 GHz"(PDF).Journal of ICT Standardization.1 (1):83–108.doi:10.13052/jicts2245-800X.115.

External links

[edit]
Current
802 series
802
802.1
802.3
(Ethernet)
802.11
(Wi-Fi)
802.15
Proposed
Superseded
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