802.11ax – the one they call Wi-Fi 6
IEEE Std 802.11ax-2021 dropped as the most ambitious WLAN update since… well, probably ever. officially led by the 802.11ax Task Group – with Osama Aboul-Magd as Chair and a crew of serious protocol pros – this was all about **high efficiency**, not just high speed.
they called it **High-Efficiency WLAN (HEW)**, and it wasn’t just hype. the world had too many devices, too much noise, too many people streaming 4K and gaming over school Wi-Fi. 802.11ax fixed that.
it operates across **2.4 GHz**, **5 GHz**, and – with Wi-Fi 6E – also the glorious new **6 GHz** band. frequencies from 1 to 7.125 GHz? yeah, it’s flexible like that.
the real game-changer? **OFDMA (Orthogonal Frequency Division Multiple Access)**. now an AP could split a single channel into **Resource Units (RUs)** and talk to multiple devices at once – no more “one-at-a-time” delays. plus **MU-MIMO** on both **uplink and downlink**, which means symmetrical high-capacity flows.
802.11ax also brought in stuff like: - **1024-QAM** modulation (because more bits per symbol = more speed) - **Dual Carrier Modulation (DCM)** - **Target Wake Time (TWT)** for power-saving (especially good for IoT) - **Guard Interval choices** (0.8 / 1.6 / 3.2 µs) - **BSS Coloring** and **OBSS_PD** for smarter spatial reuse – APs in crowded places stop stepping on each other’s signals - **HE Action Frames**, **HE Capabilities**, **HE BSS Load** – the control side got a full overhaul too
even the old **CSMA/CA** channel access mechanism got a face-lift, with features like **Punctured Preambles** for tighter timing and cleaner sharing.
802.11ax updated the base IEEE Std 802.11-2020 and will likely be folded into the next full standard release. it’s the current mainstream – **you’re probably using it right now** if your router or laptop is from the last few years.
802.11ax turned Wi-Fi into a high-efficiency beast. faster? sure. but also smarter, more predictable, and built to thrive in signal chaos. it’s the Wi-Fi dense environments didn’t know they needed, until now.