Evolution of the Technology
Wi-Fi began in 1997 with data speeds of 2 Mb/s in the 2.4 GHz and 5 GHz unlicensed bands. At this time, the IEEE 802.11 committee was developed to define standards for wireless local area networks (WLANs). Most devices utilized the 2.4 GHz band to minimize circuitry complexity and maximize WLAN reach.
As more users and devices utilized WLANs, Wi-Fi advances were needed. Initially, added features and distance coverage were necessary to support faster speeds and new modulation schemes (like orthogonal frequency-division multiplexing [OFDM]).
As more devices utilized the unlicensed band, throughput became slower. This lead to the need for improved efficiencies in transceiver-to-receiver communication (multiple-input multiple-output [MIMO]) and greater use of the 5 GHz band. The evolution is best seen in the design of wireless routers; the list of supported technologies started with IEEE 802.11a and 802.11b and now support IEEE 802.11g, 802.11n, 802.11ac and 802.11ax. The Wi-Fi Alliance’s naming convention utilizes Wi-Fi 4, Wi-Fi 5 and Wi-Fi 6 to identify equipment and devices compatible with these technologies.
Recently, in the United States, a new, unlicensed spectrum opened up in the 6 GHz band. This band is four times as large as those in the 2.4 and 5 GHz bands combined. The intention of this new band is to allow IEEE 802.11ax to thrive in an uncongested frequency band without having to be backward compatible with previous technologies. The standard that incorporates 6 GHz will be called “Wi-Fi 6E” (the “E” stands for “extended”).
New Wi-Fi standards will become instrumental as wireless connections and bandwidth requirements continue to grow. Today, the average user brings up to three devices with him wherever he goes: a smartphone, tablet and smartwatch, for example. These will all connect to a network the minute this person walks through a building’s doors (or even outside). These devices continuously download updates, receive emails and social media updates, and sync to cloud-based storage. As a result, according to Dell’Oro, wireless LAN active users are outpacing wired LAN users.
More devices are also connecting to enterprise networks as a result of Internet of Things (IoT), VoIP phones, IP surveillance cameras, lighting systems and building controls are all connecting to networks to transfer data, receive data and adjust performance in real time.
These increases in network users and wireless devices also call for more wireless access points (WAPs). (These devices connect to enterprise networks, too.)
Other Wi-Fi Technologies:
Along the way, other Wi-Fi technologies were added to serve WLAN needs and support applications with low data rates at far distances and high data rates at close distances.
In 2014, long-distance connectivity in the Sub-1 GHz band was added. Utilizing unused spectrum in the UHF television band is IEEE 802.11af (White-Fi), followed by IEEE 802.11ah (HaLow) in the unlicensed 915 MHz band. These two technologies provide WLAN connectivity with several-hundred megabits of throughput at distances of up to 1 km.
In 2016, short-haul, high-throughput connectivity was added in the 60 GHz range. IEEE 802.11ad (WiGig) offered a throughput of 6.7 Gb/s. Improvements to this technology were added in IEEE 802.11ay (Next-Generation or NG), offering up to more than 20 Gb/s of throughput and superseding 802.11ad technology.
The future of Wi-Fi will continue to advance the usage of WLANs in the 2.4 GHz and 5 GHz bands for extremely high throughput (EHT) around 25 Gb/s and play a role as a possible solution for in-building 5G off-loading. The technology contained in IEE 802.11ay, 802.11ad and 802.11ax meet ITU 2020 initiatives. The ITU initiatives are a set of requirements given to developers of radio access technologies that define 5G technologies.