HOW DOES MAX WORK?
THE LATEST EVOLUTION OF WI-FI
Max is Wi-Fi over the 802.11ax standard, with technical advancements that make it the fastest and the most versatile Wi-Fi yet. While each successive generation of Wi-Fi has been faster, Max’s improvements are not just about raw speed.
We demand a lot from Wi-Fi at home: where a family of four is expected to have an average of 50 connected devices by 2022. And we expect Wi-Fi to work hard in packed environments, like this year’s Super Bowl where fans generated an astounding 11.8 Terabytes of data posting videos, updating statuses and streaming live from the stadium. But a lot of connected devices means some serious strain on Wi-Fi routers, leading to a bottleneck of traffic. What follows are slowdowns, buffering, and less efficient networks. Max’s improvements are focused on supporting a large number of devices, operating close together, even when using large amounts of data. Below are a few of those features in detail.
The last generation of Wi-Fi introduced peak gigabit speeds by adding the ability for devices to send traffic along wider channels—80 MHz—of spectrum. Now, Max devices can achieve faster speeds than ever before, with average speeds of up to 6x faster than the last generation of Wi-Fi.
Max is capable of using up to 160 MHz wide channels—double the bandwidth—as well as faster modulations schemes such as 1024 QAM, outperforming today’s best-in-class Wi-Fi devices.
Max also uses the available spectrum much more efficiently to deliver higher average speeds to many more devices. By using Uplink and Downlink OFDMA technology, more data can flow simultaneously, stacked like a double-decker bus.
Max also has protocol changes that pack signals closer together—longer OFDM symbols—with reduced overhead compared to current Wi-Fi devices.
Orthogonal Frequency Division Multiple Access (OFDMA)
OFDMA forms the backbone of Max and makes the sixth generation of Wi-Fi more efficient, more reliable, and more versatile than previous generations. This innovation allows Max to support many devices at the same time, and to avoid the interference that causes congested Wi-Fi today.
A major factor limiting current Wi-Fi is collisions: when multiple devices transmit at the same time and interfere with each other. With OFDMA, each channel of spectrum is separated into dozens, or even hundreds, of smaller subchannels, each with a slightly different frequency. By then turning these signals through right-angles, they can be stacked closer together. Rather than waiting in line for their turn to transmit across the whole frequency band, multiple devices will be able to share each channel simultaneously. And OFDMA adds flexibility to how spectrum is used, only allocating parts of the spectrum to each wireless device proportional to its needs. This is the Wi-Fi upgrade—with vastly increased capacity—that will effortlessly power the Internet of Things while simultaneously downloading data, streaming 4K video and voice
OFDMA allows routers to dynamically adjust signal strength in an effort to improve reception for devices further away from the router. Max is essential for consumers wanting to future-proof their connected homes. Smart thermostats, doorbells, refrigerators, lightbulbs, and other devices transmit relatively small packets of data to the cloud to receive instructions or report on performance. Using OFDMA, Max efficiently combines these small packets across multiple users, and delivers gains of up to 6X in uplink, or upload, performance. Max transitions Wi-Fi from a postman, delivering mail to one house at a time to an email server, handling many messages to many users, simultaneously.
Range, coverage & robustness
Max is upgraded with multiple features to improve the range, robustness, and reliability of Wi-Fi connections.
In many scenarios, routers transmit with higher power than the devices they are communicating with--meaning the “downlink” traffic can collide with the “uplink.” OFDMA helps uplink traffic navigate busy intersections by focusing uplink traffic in a smaller slice of the spectrum. This keeps the traffic traveling in both directions from colliding and results in Wi-Fi networks capable of traveling up to 400 percent further, extending the range and the signal's reliability. So Max networks will cover more ground outdoors and have fewer dead spots indoors in larger homes, offices or venues.
For outdoor devices requiring a smaller amount of data, the standard allows data to be sent across a smaller sliver of spectrum with extra protections as the data moves longer distances; Max can improve outdoor Wi-Fi coverage for these devices by 50 percent.
Target Wake Time (TWT) for Max power efficiency
Max implements TWT, which allows the Wi-Fi radio in battery-powered devices such as phones to go to sleep when not exchanging data. This lowers power consumption and saves device battery. With TWT, Max-capable routers and mobile devices can negotiate the sleep cycle according to the data traffic, so that they only wake up when it is their turn to communicate, allowing them to preserve the battery.
Also with TWT, devices can be programmed to wake up at the same time to take advantage of OFDMA so that they can communicate at the same time. The result is a well-synchronized data flow that allows all devices to connect simultaneously and based on their needs. This improves the user experience as video, voice, data, and IoT traffic is proportioned and prioritized effectively.
Spatial Reuse - The good neighbor
Max introduces a scheme to reduce interference and use the spectrum even more efficiently by letting routers and different networks operating on the same channel to intelligently decide when they can transmit at the same time. Using this spatial reuse technique, each router and device on the same network transmits data with a unique identifier. Wi-Fi listens for interference before sending data, and will back off if it senses data in the band. With Max, when a router or a device listens first before transmitting data, they are more aggressive if they hear data from a different color, since that data is going to a different router further away.
The standard plans for two different operating modes—one optimized for dense managed networks such as stadiums and enterprises where the siting of routers is carefully planned; the other optimized for scenarios like a busy city block where routers and devices are less uniformly distributed. This allows denser deployment of Access Points to deliver increased Wi-Fi capacity to more users, while keeping interference between different networks under control.