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802.11ax and Medium Contention

As many of you might already know, a key efficiency enhancement for 802.11ax will be the use of OFDMA by Wi-Fi radios. Orthogonal frequency-division multiple access (OFDMA) is a multi-user version of the OFDM digital-modulation technology and is used in other wireless technologies such as LTE. OFDMA subdivides a channel into smaller frequency allocations, called […]

How Do 20 MHz-Only Clients Operate In 802.11ax?

Much of the 802.11ax draft amendment has been written with Internet of Things (IoT) devices in mind. The radio chipsets used for IoT devices generally need to be low-cost and consume very little power. Traditionally, Bluetooth and Zigbee chipsets have been cheaper to manufacture for IoT devices than Wi-Fi radio radios. However, 802.11ax lays the […]

What Does Multi-User (MU) Mean?

The term multi-user (MU) simply means that transmissions between an AP and multiple clients can occur at the same time dependent on the supported technology. However, the MU terminology can be very confusing when discussing 802.11ax. MU capabilities exist for both OFDMA and MU-MIMO. 802.11ax defines the use of two multi-user technologies, OFDMA and MU-MIMO. But please […]

802.11ax Frame Aggregation Enhancements

The primary goal of both 802.11n and 802.11ac was to provide high throughput and bigger data rates. However, frame aggregation is one key aspect of 802.11n/ac that did enhance airtime efficiency. Frame aggregation is a method of combining multiple frames into a single frame transmission. Fixed MAC layer overhead and medium contention overhead are reduced, […]

802.11ax Frequently Asked Questions

This article covers what the 802.11ax standard is and some common questions regarding this new standard and its accompanying features. Answers Compiled by: David Coleman, CWNE #4 Perry Correll, Aerohive’s IEEE and WiFi Alliance representative Gregor Vucajnk, CWNE #96 1. What is 802.11ax? 802.11ax is an IEEE draft amendment that defines modifications to the 802.11physical […]

Why Is OFDMA One Of The Most Important Features In 802.11ax?

Last week, I wrote about Target Wake Time (TWT), and how it was a key feature for IoT and mobile devices in 802.11ax. As exciting as that feature is, OFDMA is arguably the most important new feature correlated to 802.11ax. As a refresher, OFDMA stands for orthogonal frequency division multiple access. OFDMA is a multi-user version of […]

Does Wi-Fi Architecture Matter In 2018?

Last week, I looked at how to avoid RF interference in WLAN deployments. While this is something that affects everyone that uses Wi-Fi, the architecture your network uses is something that you can control (based on which vendor you choose). One of the primary differences between WLAN architectures is where and how the system is controlled. […]

How Will Target Wake Time Help Mobile Devices And IoT In 802.11ax?

As mentioned in a previous post, 802.11ax adds some exciting power saving enhancements and improved resource scheduling features including scheduled sleep and wake times, which is borrowed from 802.11ah. Let’s dive a little deeper. Target Wake Time (TWT) allows devices to negotiate when and how often they will wake up to send or receive data. […]

What Is BSS Coloring In 802.11ax?

Last week, we looked at the new features that 802.11ax brings to the 802.11 standard. Let’s take a closer look at BSS Coloring this week. BSS Coloring was a mechanism originally introduced in 802.11ah to assign a different “color” per BSS. Why? To increase capacity in dense environments, we need to increase frequency reuse between […]

What Does 802.11ax Change About The WLAN Standard?

Last time, we looked at the goals of the 802.11ax standard. Let’s break down some of the important changes 11ax introduces (in no particular order). First introduced in 802.11ac, MU-MIMO technology theoretically allows the simultaneous transmitting of multiple frames to different receivers at the same time on the same channel using multiple RF streams to provide […]