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Next-generation Wireless LANs in the IEEE 802.11 Working Group

NTT Technical Review Vol. 19, No. 2, Feb. 2021 provided a fantastic summary of Standardization of Next-generation Wireless LANs in the IEEE 802.11 Working Group. Here is an extract from the article:

Institute of Electrical and Electronics Engineers (IEEE) 802.11 is a working group (WG) within the IEEE 802 LAN/MAN Standards Committee that helps develop standards related to local area networks (LANs) and metropolitan area networks (MANs). It is responsible for standardization of physical layer and medium access control (MAC) layer technologies of wireless LANs.

There are several types of subgroups within the IEEE 802.11 WG. A task group (TG) is a subgroup responsible for developing a technical standard or recommended practice. A study group is a preparatory group to create a TG to discuss use cases, technologies, and feasibilities. As a result of discussion, a study group creates documents called Project Authorization Request and Criteria for Standards Development. There are also a group to discuss a specific topic called a topic interest group (TIG), standing committees, and ad hoc groups. Table 1 lists the current subgroups in the 802.11 WG.

The latest wireless LAN products with the brand name “Wi-Fi 6” that can be found in home-electronics retail stores are based on the IEEE 802.11ax standard. Although this standard defines data-transmission speed up to 9.6 Gbit/s, the maximum speed supported by actual products varies from about 1 to 5 Gbit/s depending on the price. The standardization of the IEEE 802.11ax will be completed shortly. The Wi-Fi Alliance, which provides interoperability test services, has started certification of 802.11ax devices under the brand name Wi-Fi 6.

In the United States, the 6-GHz band (from 5.925 to 7.125 GHz) was allocated for unlicensed wireless communication systems, including wireless LANs, in the spring of 2020 (see Fig. 2). By this allocation of a large frequency band, it is anticipated that interference among wireless LAN devices will be reduced. Therefore, better throughput and latency performance can be expected, which enables the accommodation of new applications requiring more bandwidth such as augmented reality and virtual reality.

In the 6-GHz band, however, there are several incumbent wireless communication systems, and the wireless LAN system needs to satisfy specific requirements to coexist with those systems. In the United States, the 6-GHz band is divided into four segments, and the technical requirements are defined for each one. There are two categories of wireless LAN devices, Low Power Indoor (LPI) and Standard Power (SP). LPI devices are allowed to use any frequency segment of the 6-GHz band but are only allowed for indoor environments. SP devices, on the other hand, are allowed to emit higher power, but are allowed to operate in only specific frequency segments, and the use of automated frequency coordination (AFC) is mandated to protect existing wireless systems. There is another category called Very Low Power (VLP) under discussion. In Japan, discussion on the unlicensed use of the 6-GHz band has not begun; however, there is strong demand from industries, and it is very likely that discussion will begin shortly.

To achieve more than 30 Gbit/s for maximum throughput at the MAC service access point (SAP), the TGbe was created in May 2019. The IEEE 802.11be standard will be published in May 2024 in accordance with the results of the discussions in the TGbe. The IEEE 802.11be will succeed the 802.11ax as the mainstream wireless LAN standard. In addition to technical topics, the TGbe is currently discussing the framework of the draft standard called Specification Framework Document. The TGbe plans to continue this discussion until May 2021 and plans to release draft version 1.0. The following features are currently being discussed for the IEEE 802.11be standard:

  • Improvement in frequency-utilization efficiency and utilization of wider bandwidth
  • Multi-link transmission
  • Multi-AP coordination
  • Low-latency features
  • Other features

The Wi-Fi Alliance is an organization to promote the adoption of wireless LAN devices and services into various market segments. It provides interoperability test services for wireless LAN products based on the IEEE 802.11 standards. A wireless LAN device that passed the interoperability test of the Wi-Fi Alliance is allowed to use the Wi-Fi certified logo.

The Wi-Fi Alliance has started interoperability testing for 802.11ax products under the brand name Wi-Fi 6 based on the draft version of the IEEE 802.11ax standard. As mentioned previously, Wi-Fi 6 certified products are currently available on the market. There are two more interoperability test services for 802.11ax products under development. One is called “Wi-Fi 6E” to test features for operations in the 6-GHz band in addition to the current Wi-Fi 6 interoperability test. The Wi-Fi 6E certification program will be launched shortly. The other one is “Wi-Fi 6 R2,” which is based on the official standard of the IEEE 802.11ax.

You can read the complete article here. You can also download the PDF after registration.

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