Abandon 2.4GHz! The new Wi-Fi standard 802.11ax is coming

In our daily router reviews or shopping guides, we always mention that a router supports IEEE 802.11ac. In fact, this is a must-see option when choosing a wireless router. It determines whether a router meets the current wireless standards and is one of the important indicators for practical applications.

From the initial advent of 802.11a, and after 802.11g, 802.11n, and 802.11ac, a new wireless standard will bring about a leap forward, that is 802.11ax.

A brief analysis of the next generation wireless standard 802.11a

Before we get into the topic, we first need to understand what Wi-Fi standards are. In fact, Wi-Fi standards are formulated by the Institute of Electrical and Electronics Engineers (IEEE), and hardware based on these standards is certified and trademarked by the International Wi-Fi Alliance (Wi-Fi Alliance, WFA for short).

Seeing this, you may ask what IEEE and WFA are? IEEE is an international association of electronic technology and information science engineers. It is currently the world's largest non-profit professional technical society, with more than 400,000 members in more than 160 countries. IEEE is committed to the development and research of electrical, electronic, computer engineering and science-related fields, and has formulated more than 900 industry standards in the fields of space, computers, telecommunications, biomedicine, power and consumer electronics. IEEE is a non-profit organization, and its activities are mainly funded by membership fees. Its headquarters is in New York City, USA.

WFA was founded in 1999. Its predecessor was WECA, which promoted the 11b standard. In 2000, it officially changed its name and began to carry out Wi-Fi product certification work worldwide (the trademark in the business circle is very familiar to everyone: Wi-Fi CERTIFIED). In 2013, it merged with the Wireless Gigabit Alliance (WiGig). Currently, the alliance has more than 200 member units, of which 42% are from the Asia-Pacific region, and there are 5 members in China. The headquarters is located in Austin, Texas, USA.

How did 802.11ax come about?

In fact, the easiest way to understand 802.11ax is to regard it as an enhanced version of 802.11ac. Like 802.11ac, it works in the 5GHz frequency band.

The difference is that 802.11ax uses MU-MIMO technology, which divides the signal into four different "signal channels" in multiple dimensions such as time domain, frequency domain, and spatial domain. Each "signal channel" can communicate with a device independently. If you find it abstract, you can think of it as a highway divided into four different lanes, which increases efficiency exponentially.

Of course, in addition to inheriting the MU-MIMO technology, another important innovation of 802.11ax is the introduction of OFDMA (Orthogonal Frequency Division Multiple Access), which can encode data on multiple subcarriers, that is, load more data into the same spatial area. This is the core technology of the next generation of high-speed wireless communication networks.

In addition, the reason why 802.11ax has attracted so much attention is that it significantly improves the throughput while effectively improving the power utilization of mobile devices. It is not just a theoretical value, but users can also achieve the effect of improving throughput in actual environments with interference sources, such as densely populated places, indoors and outdoors.

New technologies bring new challenges

While 802.11ax adopts new technologies, it also greatly increases the complexity of the design and faces new testing challenges. For example, a new test item for multiple user (MU) transmission has been added. It should be noted that MU transmission is one of the most important new features of 802.11ax, which enhances effective operation by providing transmission accuracy and STA synchronization. Therefore, various new test requirements supporting MU transmission have been released.

In addition, there are many design challenges to overcome. For example, the goal of 802.11ax is to establish indoor and outdoor channel models to improve the throughput of each station when operating indoors and outdoors. Compared with indoor channels, outdoor channels often have larger delay spread and channel time variation. Therefore, the industry selected 3GPP ITU-R Urban Micro (UMi) and Urban Macro (UMa) channel models as the benchmark for 802.11ax outdoor space channel models. Of course, appropriate improvements are needed to adapt to the new specifications.

It is undeniable that whenever a new technology emerges, it will face unprecedented new challenges, and of course corresponding solutions will also emerge. In order to obtain a faster and more stable Wi-Fi network, the 802.11ax standard is expected to improve the end-user experience, especially to achieve the goal of dense deployment. The future is here, let us wait and see.

As a winner of Toutiao's Qingyun Plan and Baijiahao's Bai+ Plan, the 2019 Baidu Digital Author of the Year, the Baijiahao's Most Popular Author in the Technology Field, the 2019 Sogou Technology and Culture Author, and the 2021 Baijiahao Quarterly Influential Creator, he has won many awards, including the 2013 Sohu Best Industry Media Person, the 2015 China New Media Entrepreneurship Competition Beijing Third Place, the 2015 Guangmang Experience Award, the 2015 China New Media Entrepreneurship Competition Finals Third Place, and the 2018 Baidu Dynamic Annual Powerful Celebrity.