Why You Should Care About IEEE 802.11ax

What is 802.11ax?

802.11ax, also known as high-efficiency wireless (HEW), is an amendment of the IEEE that defines the modifications to the previous version (802.11ac) and the improved high-efficiency operation in frequency bands between 1GHz and 6GHz.

Also known as Wi-Fi 6, 802.11ax is the most recent step in the journey of nonstop innovation. There are many improvements and features in 802.11ax, including greater flexibility, efficiency and scalability, which allow for higher speed and capacity.

The IEEE released 802.11ax publicly in 2019, and you can read the specifications on the IEEE website. For more details, the National Instruments’ 802.11ax white paper is also a great resource.

What are the benefits of 802.11ax?

Perhaps your question at this point is, “Why should I care about 802.11.ax?” To answer that question, let’s consider the chief benefits that 802.11ax brings to the table.

MIMO-OFDM

Multiple-input, multiple-output (MIMO) technology allows a wireless access point (AP) to work with up to four separate data streams simultaneously. 802.11ax brings MIMO with orthogonal frequency-division multiplexing (OFDM) to the table. What that means is 802.11ax routers can broadcast four MIMO spatial streams, giving you four times the maximum theoretical bandwidth per stream. [Learn how to determine the best internet speed for your business]

According to Jason Wingate, CEO at Emerald Ocean Ltd., OFDM “acts like a smart traffic controller, allowing multiple users to share the same channel by dividing it into smaller resource units.” Wingate added that MIMO “lets devices communicate simultaneously, along with BSS Coloring, which helps reduce interference when networks overlap.”

Mitchell Kahl, sales manager for the SMB dealer program at BCM One, said that OFDM is key to modern-day business phone systems.

“[OFDM] directly benefits businesses using VoIP solutions, as it ensures clearer voice transmission and reduced lag,” Kahl said. He also noted that his clients “have observed improved voice call quality when corporate networks migrated to Wi-Fi 6 infrastructure.” [Related article: What Is VoIP?]

Speed

The maximum throughput across multiple channels for 802.11ax is 9.6 Gbps. That’s fast, but there are always mitigating factors, such as which channel width on the 5GHz band the wireless AP uses. “802.11ax reaches [theoretical] speeds up to 9.6 Gbps, a significant increase versus 802.11ac, which can reach [theoretical] speeds up to 3.6 Gbps,” Wingate said.

Why does anybody need that much network speed? Well, imagine performing any of these actions with nearly zero lag:

• Streaming 4K (ultra high-definition) video
• Downloading full retail games to your console
• Meshing your smart household appliances with no latency

Given the cost of some high-end Wi-Fi hardware, it’s good news that 802.11ax is backward-compatible with the existing ― and in some cases older ― 802.11a/b/g/n/ac standards.

Reception

The Wi-Fi standards moved to the 5GHz band to reduce contention with 2.4GHz household appliances. 802.11ax operates on both the 5GHz and 2.4GHz bands, but the IEEE designed it specifically for high resiliency. The informal title of the 802.11ax specification is HEW.

The IEEE has architected 802.11ax to provide steady, resilient performance even in Wi-Fi-dense areas. For example, think of how many wireless local area networks (WLANs) compete on both the 2.4GHz and 5GHz bands in a typical high-rise apartment building. 

Range

802.11ax has a 230-foot indoor range and an 820-foot outdoor range. For comparison, 802.11ac ― the previous Wi-Fi standard ― had an approximate indoor range of 150 feet and an approximate outdoor range of 300 feet. [Learn what to look for in an internet service provider.]

What are its features, and what problems does 802.11ax solve?

802.11ax has introduced a wide range of new features, including a much-needed increase in the standard quality of service, which is an industry term for how Wi-Fi resources are used. Here are some of the new and improved features you’ll see with 802.11ax:

Target Wake Time (TWT)

The TWT enhancement helps to extend the battery life on smartphones and other mobile devices through better sleep and wake efficiency, which means maintaining the connections of Wi-Fi when smartphones and other mobile devices are inactive (the older version used a lot of battery life when not in use). 

“Target Wake Time schedules when devices should wake up to receive data, reducing energy consumption,” explained Wingate. [Read more about point-to-point wireless.]

Better Wi-Fi experience

802.11ax addresses the complexity of the frequency bands used in Wi-Fi. It improves capacity and allows individual devices to connect to Wi-Fi more quickly and easily. This is especially beneficial in areas with overlapping coverage, such as school settings, apartment buildings, airports and train stations. 802.11ax offers improved performance, especially in these areas of overlapping coverage.

Downlink and uplink OFDMA

OFDMA increases user data rates and reduces latency, especially on devices with short frames or low data rate requirements, such as Internet of Things devices. 802.11ax has multiuser capacity, meaning a transmission can be divided in the frequency domain with various groups of subcarriers with frames for different destinations.

Outdoor operation

Various features improve 802.11ax’s outdoor performance, but the most important is a new packet format where the most sensitive field is now repeated. Other features include modes that introduce redundancy to allow for error recovery and longer guard intervals.

The future of 802.11ax & introduction of 802.11be

IEEE 802.11ax, certified in 2020, has become the standard for WLAN technology, offering better performance, coverage and battery life than its predecessor. However, IEEE and Wi-Fi Alliance are already planning for the future IEEE 802.11be (Wi-Fi 7). 

“Looking ahead at how 802.11ax sets the stage for IEEE 802.11be, the next generation will build on 802.11ax’s foundations,” Wingate said. He added that 802.11be will promise “even wider channels (320 MHz for more data throughput), more sophisticated modulation (4K-QAM for even more data per transmission) and MLO (Multi-Link Operation — the ability to use multiple bands simultaneously).”

Kahl said that 802.11be will foster VoIP improvements. “[802.11be will be] critical for cloud-based communications, as it aligns with the shift towards higher bandwidth applications like video conferencing, which are becoming standard in remote and flexible work setups,” Kahl said.

The IEEE is close to ratifying 802.11be. As of October 2024, most of the boards that must approve the protocol have done so. Only 802 EC, RevCom and SASB must still give their approval, and all are expected to do so by December 2024. Thereafter, it may take several years for Wi-Fi 7 devices to become readily available.

How will 802.11be improve on 802.11ax?

Below is more information on the most significant improvements for Wi-Fi 7:

• MIMO enhancements: Wi-Fi 7 is expected to bring coordinated multiuser MIMO (CMU-MIMO), which will support 16 data streams on all three frequencies simultaneously.
• Multilink operation: Wi-Fi 7 aims to enhance multilink operation technology by increasing throughput, lowering latency and improving reliability, enabling devices to simultaneously transmit and receive across different bands and channels.
• AP coordination: The Wi-Fi 7 Working Group plans to improve AP coordination by introducing enhancements, such as OFDMA, spatial reuse, time-division multiple access, beamforming and joint processing to reduce collisions and improve overall network performance.
• 320 MHz transmissions: The maximum channel size will double from 160 MHz with Wi-Fi 6 to 320 MHz, which also doubles the throughput. Wi-Fi 7 also supports 160+160 MHz, 240+180 MHZ and 160+80 MHz channels.
• Higher modulation: Typically, wireless networks utilize quadrature amplitude modulation (QAM), and it is anticipated that Wi-Fi 7 will support 4096-QAM — increasing throughput by 20 percent. 
• Enhanced OFDMA: Wi-Fi 6 introduced OFDMA, and it will continue with Wi-Fi 7 with more flexibility and increased spectrum efficiency. 
• Low latency: The enhancements listed above will help decrease latency, which will become less variable and more predictable.

Connecting the dots

802.11ax, the current Wi-Fi standard, is excellent. That said, when 802.11be drops, even higher-quality Wi-Fi will be available. This new Wi-Fi protocol will empower each of the devices connected to your business network to function more efficiently. Yes, Wi-Fi is changing — and it’s all for the better.

Max Freedman contributed to the this article.