How Wi-Fi Progress Helps 8K Distribution
To understand how the future of Wi-Fi might affect 8K distribution, I interviewed Quentin Feraboli, a deep-tech Wi-Fi expert from the French software developer and home gateway specialist SoftAtHome.
Wi-Fi matters for consumers and pros alike
In an ideal world, to optimize the network and lower energy consumption at home, devices used for streaming would use a wired network such as Ethernet. However, many users are unable or prepared to set up such networks in their homes. We don’t have reliable figures about how many TVs stream wirelessly instead of through wired networks, but we know wireless is a significant proportion.
For professional workflows, there are also situations where Wi-Fi is the most effective solution, especially now that versions of 8K RAW can be delivered flawlessly with 1 Gbps.
With OFDMA, Wi-Fi 6 already improves 8K transmissions within the home
Firstly, Quentin explained that Wi-Fi 6 had already introduced OFDMA (Orthogonal Frequency-Division Multiple Access), a step up from OFDM (Orthogonal Frequency-Division Multiplexing).
The previous technology was already there to improve wireless capacity. The new tech creates independent simultaneous data channels for different users. Wi-Fi 6 improves bandwidth by 40% for the same number of antennas with OFDM-enhanced modulation.
OFDMA, also used in 5G cellular networks, improves wireless network performance by independently modulating subcarriers within frequencies. The innovation here is to temporarily divide Wi-Fi channels into smaller units – each attributed to a specific end device – to address the growing number of users on any Wi-Fi access point. The older OFDM approach time multiplexes different devices over a single frequency. There is scope for optimizing further with an intelligent mix of OFDM and OFDMA, especially where resources can be an issue, as can be the case with 8K.
As we’ve often reported here, the first commercial 8K streams were in the 100 Mbps range, and we’re already seeing carrier-grade solutions as low as 50 Mbps.
So, in a geeky home with dozens of devices, before OFDMA, all the devices could clog up the Wi-Fi by asking to “talk” even if they didn’t need much bandwidth. Now just the device that requires a large bandwidth is allocated it.
The journey of individual packets gets optimized within the home LAN, with access points (typically the home gateway) being able to orchestrate traffic and give the right priorities (i.e., better bandwidth for 8K streaming and lower latency for gaming, or both with video conferencing, etc.).
There is, however, still a tradeoff between bandwidth and latency.
Wi-Fi Multimedia (WMM) is a great concept but not always easy to implement
WMM is a fifteen-year-old interoperability certification program sponsored by the Wi-Fi Alliance and based on IEEE 802.11e that maintains separate priority queues for audio, video, and voice over less time-critical uses. It mainly impacts latency. The traffic is prioritized as follows:
- The background traffic queue has the lowest priority, typically for downloading large files.
- Best Effort traffic comes next as a medium-priority queue used by most applications.
- The video queue has the second highest priority. Video-only apps use this queue.
- The top priority queue, with the lowest latency, is used for voice apps and some streaming media.
These priority queues show their age, as there are none for gaming or work-from-home. The difficulty is not in using WMM but in detecting the customer’s services and attributing the correct quality of service.
Lionel Grémeau, one of SoftAtHome’s product marketing directors, told me, “This queue system has allowed for better efficiency in Wi-Fi but implementing it effectively requires more intelligence. Because of encryption, identifying WhatsApp traffic as voice can, for example, be tricky. If nothing is done, it will be treated only with the best effort. Software solutions identifying the type of service or traffic using machine learning and fingerprinting techniques, such as SoftAtHome is proposing, are interesting. But this opens two cans of worms; privacy and net neutrality. It will be the choice of operators whether to deliver these offers with better Wi-Fi traffic management.”
On the professional workflow side
Earlier this year, IntoPIX released their lightweight TicoXS FIP solution, which allows content creators to transmit 8K files that behave like RAW files with some ultra-low-latency lossless compression. Such feeds can use older cabling supporting just 1Gbps and now Wi-Fi too.
What can we expect from Wi-Fi 7?
The future Wi-Fi standard will deliver bandwidth up to 320MHz per channel compared to the current 160MHz per channel. Perhaps most crucially, Wi-Fi 7 can use all three radio bands simultaneously (2.4GHz, 5GHz, and 6 GHz) for a single connection. This feature is called Multi-Link Operation (MLO). Wi-Fi 7 allows up to 46 Gbps links with 320 MHz and 16 antennas.
Solutions have been announced for a while now. A year ago, we wrote about Qualcomm’s latest chipset here, and MediaTek, for example, announced earlier this year that their Wi-Fi 7 Filogic platforms with 8K cited as a likely use case.
As soon as we have enough relevant data, we’ll update this article with the version of Wi-Fi used by 8K TVs in the market.
