ARRIS SURFboard G54: 1st DOCSIS 3.1 Cable Gateway to Feature Wi-Fi 7

ARRIS SURFboard G54: 1st DOCSIS 3.1 Cable Gateway to Feature Wi-Fi 7

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Below are the major improvements the new Wi-Fi 7 standard will bring when fully certified.

1. The all-new 320MHz channel width

The first is the new and much wider channel width, up to 320MHz or double that of Wi-Fi 6/6E.

This new channel width is generally available on the 6GHz band, with up to three 320MHz channels. However, Wi-Fi 7 can combine portions of the 6GHz and 5GHz bands to create this new bandwidth — more in the Multi-Link Operation section below.

Details of Wi-Fi channels can be found here, but the new channel width generally means Wi-Fi 7 can double the base speed, from 1.2Gbps per stream (160MHz) to 2.4Gbps per stream (320MHz).

So, in theory, just from the width alone, a 4×4 broadcaster 6GHz Wi-Fi 7 can have up to 9.6 Gbps of bandwidth — or 10Gbps when rounded up. But there’s more to Wi-Fi 7’s bandwidth below.

Depending on the configuration, Wi-Fi 7 routers and access points will be available in different speed grades, including those offering bandwidths higher or lower than 10Gbps on the 6GHz band.

Wi-Fi 7 also supports double the partial streams, up to 16. As a result, technically, a 16-stream (16×16) Wi-Fi 7 6GHz band can deliver up to over 40Gbps of bandwidth, especially when considering the new QAM support below.

Again, you need a compatible client to use the new 320MHz channel width. Existing clients will connect using 160MHz at best. In reality, the 160MHz will likely be the realistic sweet-spot bandwidth of Wi-Fi 7, just like the 80MHz in the case of Wi-Fi 6.

2. The 4K-QAM

QAM, short for quadrature amplitude modulation, is a way to manipulate the radio wave to pack more information in the Hertz.

Wi-Fi 6 supports 1024-QAM, which itself is already impressive. However, Wi-Fi 7 will have four times that, or 4096-QAM. Greater QAM means better performance for the same channel width.

As a result, Wi-Fi 7 will have a much higher speed and efficiency than previous standards when working with supported clients.

Wi-F 7 vs Wi-Fi 6/6E: The realistic real-world speeds

With the support for the wider channel width and higher QAM, Wi-Fi 7 is set to be much faster than previous standards.

The table below summarizes what you can expect from Wi-Fi 7’s real-world organic performance compared to Wi-Fi 6E when working on the 6GHz.

Wi-Fi 6E Wi-Fi 7
Max Channel Bandwidth
(theoretical/top-tier equipment)
160MHz 320MHz
Channel Bandwidth
(widely implemented)
80MHz 160MHz
Number of Available Channels 7x 160MHz or 14x 80MHz channels 3x 320MHz or 6x 160MHz channels
Highest Modulation 1024-QAM 4096-QAM
Max Number
of Spatial Streams
(theoretical on paper / commercially implemented)
8 / 4 16 / 8 (estimate)
Max Bandwidth
Per Stream
(theoretical)
1202Mbps (at 160MHz)
600Mbps (at 80Hz)
2.9Gbps
(at 320MHz)
1.45 Gbps (at 160MHz)
Max Band Bandwidth
(theoretical on paper)
9.6Gbps
(8×8)
46.1Gbps
(16×16)
Commercial Max Band Bandwidth Per Band
(commercially implemented)
4804Mbps
(4×4)
23Gbps
(8×8)
Actual Available Max Real-word Negotiated Speeds(*) 2402Mbps
(via a 2×2 160MHz client )
1201Mbps
(via a 2×2 80MHzclient)
11.5Gbps
(via a 4×4 320MHz client)
5.8Gbps
(via a 2×2 320MHz client or a 4×4 160MHz client)
2.9Gbps
(via a single stream 320MHz client or a 2×2 160MHz client)
1.45Gbps
(via a single stream 160MHz client or a 2×2 80MHz client)
Wi-Fi 6 vs Wi-Fi 7: Theoretical data rates on the 6GHz band
(*) The real-world sustained speeds depend on the client and environment and generally are much lower than negotiated speeds. Wi-Fi 6/6E has had only 2×2 clients. Wi-Fi 7 will also use 2×2 clients initially, but it might have 4×4 and even single-stream (1×1) clients.

Multi-Link Operation, or MLO, is the most exciting and promising feature of Wi-Fi 7 that changes the norm of Wi-Fi: Up to Wi-Fi 6E, a Wi-Fi connection between two direct devices occurs in a single band, using a fixed channel at a time.

In a nutshell, MLO is Wi-Fi band aggregation. Like Link Aggregation (or bonding) in wired networking, MLO allows combining two Wi-Fi bands, mostly 5GHz and 6GHz, into a single Wi-Fi network (SSID) and connection. The bonded link delivers higher bandwidth and reliability.

MLO only works at its full potential with Wi-Fi 7 clients, and in this case, it can be a game-changer in a wireless mesh network. We can potentially count on having no signal drop or brief disconnection. And it’s also when seamless handoff (or roaming) can become truly seamless.

On top of that, on each band, a connection can also intelligently pick the best channel, or channel width, in real time. In other words, it can channel-hop, just like Bluetooth, though likely less frequently.

This new capability will help increase the efficiency of Wi-Fi 7’s range, allowing all its bands to deliver faster speed over longer distances than previous standards.

Here are the Wi-Fi setting pages of the One Plus 11 5G. Note how it has the new “Dual Wi-Fi acceleration.” Also, a Wi-Fi 7 broadcaster, such as TP-Link Deco BE85 used in the screenshot above, will have a separate MLO network in addition to the existing traditional network for backward compatibility.

In more ways than one, MLO is the best alternative to the existing so-called “Smart Connect” — using the same SSID (network name) and password for all the bands of a broadcaster — which doesn’t always work as smartly as expected.

But MLO is not all perfect — a few things to keep in mind:

  • MLO only works with Wi-Fi 7 clients. Older clients, such as Wi-Fi 6 or 6E, will still use a single band at a time when connecting to a MLO SSID.
  • MLO requires the WPA3 encryption method and generally won’t work with Wi-Fi 5 or older clients.
  • The reach of the combined link (of 5GHz and 6GHz) is as far as the range of the shorter band.

By default, the 6GHz band has just about 75% of the range of the 5GHz when the same broadcasting power is applied. That said, MLO can only be truly meaningful with the help of Wi-Fi 7’s next feature, Automated Frequency Coordination.

4. Automated Frequency Coordination

Automated Frequency Coordination (AFC) applies only to the 6GHz band, which is the fastest yet the shortest range compared to the 5GHz and 2.4GHz. It’s an optional feature — it’s not required for the general function of a Wi-Fi 7 broadcaster.

At any given time, there can be existing applications already using the spectrum. For example, fixed satellite services (FSS) or broadcast companies might have already had called dibs on certain parts of the 6GHz band. A new Wi-Fi broadcaster must not impact those existing services — a concept similar to DFS channels in Wi-Fi 6 and 5.

That’s when the AFC feature comes into play. The idea is that all new 6GHz broadcasters check with a registered database in real-time to confirm their operation will not negatively impact other registered members. Once that’s established, the broadcaster creates a dynamically exclusive environment in which it can operate without the constraint of regulations like the case of Wi-Fi 6E and older standards.

Specifically, the support for AFC means each Wi-Fi 7 broadcaster can use more power and better flexible antenna designs. How much more? That depends.

But it’s estimated that AFC can bring the broadcasting power up to 36 dBm (from the current 30 dBm max) or 4 watts (from 1 wat). It’s safe to say AFC will help the 6GHz band to have a comparable range to the 5GHz band — about 25% more.

Before you get all excited, this feature requires certification, and its availability is expected to vary from one region to another. It won’t be available in the US before late 2023, if not after. All hardware released before that is said to be capable of handling AFC, which can be turned on via firmware updates.

A crude AFC analogy

Automated Frequency Coordination (AFC) is like checking with the local authorities for permission to close off sections of city streets for a drag race block party.

When approved, the usual traffic and parking laws no longer apply to the area, and the organizers can determine how fast traffic can flow, etc.

Wi-Fi 7’s other improvements

On top of that, Wi-Fi 7 will also have other improvements, including support for Flexible Channel Utilization (FCU) and Multi-RU.

With FCU, Wi-Fi 7 handles interference more gracefully by slicing off the portion of a channel with interference, 20MHz at a time, and keeps the clean part usable, as opposed to the case of Wi-Fi 6/6E, when there’s interference, an entire channel can be taken out of commission. FCU is the behind-the-scene technology that increases the efficiency of Wi-Fi, similar to the case of MU-MIMO and OFDMA.

Similarly, with WiFi 6/6E, each device can only send or receive frames on an assigned resource unit (RU), which significantly limits the flexibility of the spectrum resource scheduling. WiFi 7 allows multiple RUs to be assigned to a single device and can combine RUs for increased transmission efficiency.



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