The Journey to Wi-Fi 7

Qorvo at the Forefront of Wi-Fi FEM Technology

Steve Taranovich for Mouser Electronics

Introduction

Significant strides in efficiency and capacities have marked the transition from Wi-Fi® 5 to Wi-Fi 6. The advent of Wi-Fi 6E then ushered users into the new 6GHz spectrum, paving the way for marked improvements in efficiency, capacity, speed, and spectrum that form the foundation for Wi-Fi 7. Now on the horizon, the Wi-Fi 7 standard, built upon features outlined in the IEEE P802.11be draft amendment, promises to deliver speeds over four times faster than its predecessor, Wi-Fi 6 (802.11ax).

But what led to this leap in wireless speeds, setting the stage for the next generation of routers? To understand this, one must consider the evolution from Wi-Fi 6 and 6E, which provided maximum speeds of just under 10Gbps, significantly slower compared to the 46Gbps that Wi-Fi 7 promises. In this new era of connectivity, Wi-Fi 7 harnesses the power of the 2.4GHz, 5GHz, and 6GHz spectrum bands, earning it the name Extremely High Throughput (EHT) wireless.

An essential part of this story is the contribution of companies like Qorvo®, who are instrumental in bringing Wi-Fi 7 to life. Qorvo's leading-edge technologies, especially in front-end modules (FEMs), play a crucial role in shaping the new frontier of wireless communication that Wi-Fi 7 represents.

As we delve deeper into this exciting progression in wireless technology, let's focus on what lies ahead. With its groundbreaking features and transformative potential, it's clear that the era of Wi-Fi 7 is just around the corner.

Wi-Fi 7 Is on the Way

Wi-Fi 7 increases channel size, going from a bandwidth of 160MHz in Wi-Fi 6 and Wi-Fi 6E to 320MHz in the new standard. Twice the channel bandwidth doubles the throughput, with uplink speeds of greater than 5Gbps and about 2.4Gpbs expected in the downlink. Wi-Fi 7 also offers essential advances to build upon efficiency. Thanks to the new standard's ability to share channels and frequency bands, users will experience ultra-low deterministic latencies, increased reliability, and advanced security features.

Since the new Wi-Fi 7 protocol has double the channel width, devices like routers will now be capable of supporting many more users than Wi-Fi 6. Additionally, the reduced latency as compared to Wi-Fi 6 will allow Wi-Fi 7 to become the perfect option for gaming and videoconferencing. The increased channel size and throughput will also enable advanced augmented reality (AR) and virtual reality (VR) applications.

Wi-Fi 7 User Benefits

Wi-Fi 7 stands to offer users several advantages over previous versions, including improved privacy and security, greater capacity for more connected devices, and responsiveness on par with wired devices. Additional benefits include:

• Improved connectivity: With speeds greater than 5Gbps and consistent ultra-low latency, users can share files in seconds rather than minutes. Users' devices can also make and maintain the best Wi-Fi connections simultaneously.
• Lower latency and better response time: Wi-Fi 7 enhances these features by using enhanced orthogonal frequency-division multiple access (OFDMA) and smart device optimization.
• Increased capacity and spectrum efficiency: These improve performance in public places and dense environments.
• Multi-Link Operation (MLO): Wi-Fi 7 devices can simultaneously connect to two bands. This feature enables faster speeds through aggregation (i.e., both bands can be used concurrently to share redundant/unique data for improved reliability with ultra-low and precise latencies).
• Improved bandwidth: Wi-Fi 7 has bandwidth capability up to 320MHz (as opposed to 160MHz from Wi-Fi 6). Both bandwidths are supported.
• Backward compatibility: Wi-Fi 7 is backward compatible and will coexist with legacy devices in 2.4GHz, 5GHz, and 6GHz spectrum bands.
• MAC and PHY improvements: These improvements enable a maximum throughput of 30Gbps (up to 46Gbps), which increases system performance, expands use cases, and enables innovations in Wi-Fi.
• Higher throughput and data rate: Users will have up to 5.8Gbps using a 320MHz channel and 4096 quadrature amplitude modulation (QAM).

Benefits of QAM in Wi-Fi 7

One of the main enhancements in Wi-Fi 7 is 4K-QAM (4096-QAM). But what exactly is QAM?

QAM has been used throughout the Wi-Fi standards. It translates the digital packets into an analog signal that wirelessly transfers data. QAM combines two amplitude modulation (AM) signals into a single channel, helping to double the effective bandwidth. As such, spectral efficiency is improved via the incorporation of more data into each transmission.

4K-QAM (4096-QAM) is defined as a QAM using 4096 (212) constellation points arranged in a square, each symbol carrying 12 bits. Packing more data, 4K-QAM enables a 20 percent data rate increase in Wi-Fi 7 compared to 1024-QAM of Wi-Fi 6.

4K-QAM enables a higher data transmission rate with higher spectral efficiency. This is most important for consistently serving many clients and will ensure fast and reliable Wi-Fi coverage in high-density deployment applications.

Wi-Fi 7 Applications

The arrival of Wi-Fi 7 will enhance many existing Wi-Fi applications as well as create new ones that capitalize on the standard's additional benefits.

Smart Home
Increased throughput, lower latency, and MLO mean new data-centric applications in the smart home. For example, a VR gaming link needs a great deal of data at very low latency to operate. When you turn your head, you expect to see the video in your headset turning with you in real time. MLO adds capabilities to the Wi-Fi management system that utilizes different radios for a common client to simultaneously send and receive data across different frequency bands and channels.

Customer Premises Equipment
Wi-Fi 7 router technology is poised to bring home networking to the highest level with speeds as high as 46Gbps. Wi-Fi 7 routers have faster upload and download speeds.

MIMO
Multiple-input, multiple-output (MIMO) communications enable routers to transmit a signal using many carrier signals at different frequencies, allowing parallel data transfer as opposed to serial transmission. For example, a router with two 5GHz Wi-Fi antennas can support 2×2 multiple input multiple output (MIMO); three antennas support 3×3 MIMO, four antennas support 4×4 MIMO, and so on, all the way to 16×16 MIMO.

The larger the number of MIMOs, the larger the network throughput will be. n×n MIMO is like a highway in which n refers to the number of highway lanes. The lane throughput is n times the capacity of any single lane. For example, a single lane (antenna) rate of Wi-Fi 6 at 80MHz offers speeds of about 600Mbps. Therefore, 2×2 MIMO would offer close to 1200Mbps, 3×3 would offer 1800Mbps, etc.

MU-MIMO
In previous Wi-Fi versions, multiple devices used a router's network. They did not connect simultaneously, instead waiting their turn for transmission. Wi-Fi 7's multi-user MIMO (MU-MIMO) capability modifies this one-to-one transmission/reception to a one-to-multiple transmission/reception, thus enabling multiple devices to access the network without waiting.

MU-MIMO technology will significantly increase the throughput and reduce network congestion and delays if a network is full of devices. This helps enable each device with a high priority, thus allowing the entire network to provide stable and fast performance even if older, lower-speed devices connect.

Wi-Fi 7 significantly advances communications with 16×16 MU-MIMO. Here, the maximum number of data lanes is sixteen, double the prior generation’s spatial streams. So now it will enable communication with as many as sixteen devices on every stream; this is a key reason why the throughput rates of Wi-Fi 7 are considerably larger than those of Wi-Fi 6. In addition, 16×16 MU-MIMO will tremendously improve the data throughput of individual devices in addition to expanding Wi-Fi coverage.

Front-End Modules: Critical Wi-Fi Router Components

Wi-Fi FEMs are compact, integrated modules designed to manage and optimize the RF functions of a Wi-Fi system. Wi-Fi FEMs help design engineers streamline the design process, offering a combination of performance, size, and cost benefits by incorporating discrete components such as power amplifiers (PAs), switches, and low-noise amplifiers (LNAs) into a single package.

Qorvo QM45500 FEM
The Qorvo QM45500 is a 2.0mm × 2.0mm 5Ghz–7GHz Wi-Fi front-end module (FEM) designed for Wi-Fi 7 systems. This FEM includes an optimized PA, single-pole, three-throw (SP3T) antenna switch, and a bypassable LNA.
This FEM has a small form factor coupled with integrated matching, which will minimize the circuit board footprint. In addition, the QM45500 has multiple Wi-Fi transmit (TX) modes that optimize linearity and output power with a power dissipation that preserves power consumption. The FEM also achieves the highest level of linear power output with state-of-the-art throughput.

The receive path easily matches the chosen technology, maximizing receive sensitivity via an exceptional noise figure performance that remains consistent across many conditions. The FEM has onboard die-level filtering for second and third harmonics. There is also a 2.4GHz rejection capability for dual-band dual-concurrent (DBDC) operation. An integrated power coupler optimizes closed-loop power control and digital pre-distortion (DPD). The on-chip DPD provides an excellent method to linearize the PA and improve efficiency.

Qorvo QPF7250 iFEM
The Qorvo QPF7250 is a 2.4GHz Wi-Fi integrated front-end module (iFEM) optimized for Wi-Fi 7 and Wi-Fi 6 and 6E applications. The iFEM combines the advantages of active components with edgeBoost™ filter technology. The QPF7250 integrates a 2.4GHz PA with DC and RF power detectors, an FCC edgeBoost BAW filter, a transmit-receive switch, and a bypassable LNA in a single device (Figure 1).

 
Figure 1: Block diagram of the Qorvo QPF7250 Wi-Fi 7 edgeBoost iFEM. (Source: Qorvo)

Conclusion

The advent of Wi-Fi 7 represents an exciting milestone in the ongoing evolution of wireless technology. Many technical advances have led to the groundbreaking technology that enables Wi-Fi 7's significant improvements over Wi-Fi 6 and Wi-Fi 6E, including wider channels, higher QAM, and MLO.

However, the gradual introduction of Wi-Fi 7 will not render Wi-Fi 6 obsolete. The complementary technologies will coexist over the next few years, creating a diverse wireless ecosystem that caters to various user requirements and application scenarios.

At the heart of these developments, key players like Qorvo play an instrumental role in transforming Wi-Fi 7 from a concept into a reality. The contribution of their advanced FEM components, integrated with superior features like 16×16 MU-MIMO and edgeBoost filter technology, is set to drive the future of wireless communication and elevate user experiences.

As we move closer to the expected introduction of Wi-Fi 7 in 2024, we look forward to experiencing the transformative impact the technology will undoubtedly have on the way we connect, communicate, and interact with the world around us.