Wi-Fi 7 Solutions Gear Up for Next-gen System Designs
With Wi-Fi 7 on the horizon, silicon vendors have already started introducing solutions supporting the new Wi-Fi specifications.
With emerging video applications, including augmented reality (AR), virtual reality (VR), and online gaming, the throughput requirement of multimedia delivery will keep growing and reach far beyond the capabilities of the WLAN (Wireless Local Area Network) standard: Wi-Fi 6.
To meet these emerging demands, the IEEE 802.11 will release a new standard, IEEE 802.11be, also known as Wi-Fi 7. As of now, Wi-Fi 7 is in a draft stage, with the Wi-Fi Alliance reportedly releasing Draft 2.0 of the Wi-Fi 7 spec back in July.
In this article, we’ll examine the history of Wi-Fi, explain what’s in Wi-Fi 7, and look at developments from chip vendors aimed at Wi-Fi 7.
From CSMA to OFDMA
Since Wi-Fi was first released in 1997, the standards are constantly evolving, resulting in faster speeds and higher spectrum efficiency for users. Early Wi-Fi standards used carrier sense multiple access (CSMA) protocol in which a channel's traffic is checked before beginning the data transmission. Then came the orthogonal frequency division multiplexing (OFDM) protocol, in which data is enclosed on multiple carrier frequencies.
Shown here are the pre-Wi-Fi 7 versions of Wi-Fi.
Shown here are the pre-Wi-Fi 7 versions of Wi-Fi. Image used courtesy of Intel (Click image to enlarge)
Wi-Fi 5 accelerated the Wi-Fi standard by providing a gigabit data rate per second. It included a wider bandwidth of 100 MHz, more MIMO spatial streams, and high-density modulation of up to 256 QAM (Quadrature Amplitude Modulation). Its successor, Wi-Fi 6/6E, provided four times greater scalability by utilizing the OFDMA protocol.
OFDMA combines transmission packets and sends them to multiple endpoints simultaneously. It increases network throughput by three times. It also featured improved security and 75% lower latency, thanks to 1024 QAM high-density modulation.
W-Fi 6E adopted several new technologies. Wi-Fi 7 will use some of these technologies and new ones to make full use of the new 6 GHz spectrum. It combines several technologies such as automated frequency coordination, multiple link operation, and 4K QAM to increase wireless capabilities, reduce latency and make Wi-Fi more flexible and responsive to the users.
Automated Frequency Coordination (AFC)
As mentioned earlier, Wi-Fi 7 leverages some technologies that debuted in Wi-Fi 6E. AFC is one of these technologies. Wi-Fi 6E and Wi-Fi 7 tap into the 6 GHz regime. However, weather radar systems and radio astronomers also rely on this frequency band.
AFC makes it possible for WLAN to operate around incumbents by transmitting in bands that don't interfere with the other systems. It also increases the throughput of the system when no other systems nearby are using this spectrum.
Multiple resource units allocation.
Multiple resource units allocation. Image used courtesy of Intel (Click image to enlarge)
To achieve such frequency coordination, IEEE 802.11ax supported resource units (RU) assignment to the users by puncturing the operating channel. In Wi-Fi 6, each user is assigned to a specific RU for transmitting and receiving data frames, which limits the flexibility of the spectrum. Wi-Fi 7 solves this problem by allocating multiple RUs to each user, enhancing spectral efficiency.
Multi-Link Operations (MLO)
MLO takes advantage of the fact that Wi-Fi's existing 5 GHz band and new 6 GHz band are relatively closer. This feature will allow devices to connect to both channels simultaneously to send and receive data. The two channels can also be used in tandem, which means if a connection is slow, the data communication can take place in another.
MLO, along with the features operating at MAC (Media Access Control) and the physical layer of the network, will help bring Wi-Fi 7 latency to less than 10 ms.
The MLO has the potential for a significant throughput increase, but it also calls for more possible combinations of phase and amplitude corresponding to different binary data sequences. Therefore, Wi-Fi 7 uses 4096 QAM, a modulation scheme to transmit 12 bits per symbol. In other words, it can superimpose 4096 signals at once.
The Shift Towards Wi-Fi 7
At an Asia Pacific press conference in July, Intel recently announced its plan to commercialize Wi-Fi 7 in 2024 with double the frequency bandwidth of Wi-Fi 6, according to an article in Korean IT News. Intel reports the next-generation WLAN standard has 2.4 times faster processing speeds than 5.8 Gbps and supports a maximum speed of 36 Gbps when transforming data.
Intel says it predicts that Wi-Fi 7 will advance technologies, including gaming, AR, VR, and robotics. Several additional features for Wi-Fi 7 are under consideration for the final standard. In the Korean IT News article, vice president and general manager of Intel’s Wireless Solutions Group noted that there is more than a year left before the final release of 802.11be. With that in mind, “there is still a chance that we could improve the processing speed even further," he says. However, Qualcomm and MediaTek are already preparing to release Wi-Fi 7-based products.
MediaTek’s Complete Wi-Fi 7 Platform
In late May, MediaTek announced the Filogic 880 and Filogic 380 Wi-Fi 7 platforms for high bandwidth applications in the electronics segment. The Filogic 880 combines Wi-Fi 7 access point with an advanced host processor and network processing unit to support Wi-Fi, Ethernet, and packet processing performance.
MediaTek’s Filogic 880 and Filogic 380 Wi-Fi 7 devices target high bandwidth applications.
MediaTek’s Filogic 880 and Filogic 380 Wi-Fi 7 devices target high bandwidth applications. Image used courtesy of MediaTek
The Filogic 880 features a scalable architecture that supports up to pentaband 4x4 with a maximum speed of 36 Gbps. It also offers various interfaces and peripherals for flexibility in design.
Meanwhile, the Filogic 380 is a single-chip 6 nm Wi-Fi 7 and Bluetooth 5.3 solution for optimized connectivity. It supports Wi-Fi technologies, such as MLO, multiple RUs, and 4K QAM. Moreover, it features up to 5 Gbps data speed per channel and dual 2x2 radios for dual-based simultaneous operation.
Qualcomm’s Wi-Fi RF Front End Modules
In June this year, Qualcomm Technologies announced new RFFE (Radio Frequency Front End) modules targeting Wi-Fi and Bluetooth applications. The modules are designed for smartphones, automotive technologies, computers, wearables, the Internet of Things (IoT), and more. More information can be found in Qualcomm’s blog post about the front ends.
Qualcomm’s RF Front Ends (RFFEs) integrate power amplifiers (PA), low noise amplifiers (LNA), filters, and switches packaged in a module.
Qualcomm’s RF Front Ends (RFFEs) integrate power amplifiers (PA), low noise amplifiers (LNA), filters, and switches packaged in a module. Image used courtesy of Qualcomm
Qualcomm says its Wi-Fi RFFE modules consist of vital components like duplexers, diplexers, extractors, and acoustic filters to condition signals for optimal wireless transmission. The products complement Qualcomm ultraBAW, and ultraSAW filter technology, improving their RF performance to help OEMs easily develop power-efficient wireless solutions.
Wi-Fi 7 Poised for Success
If there’s any lesson to be learned from the history of Wi-Fi it’s that these protocols take time to move from spec development to technology development, and then finally to product development. With the stakes always high in this profitable market segment, engineering work on chips, routers, and other gear has to start rolling in parallel with specification work, and apparently that’s all going full steam with Wi-Fi 7.