IEEE 802.11be throughput performance

Achieve extremely high throughput and more

To meet the goals of IEEE 802.11be, Wi-Fi 7 introduces several new features focused on:

• Expanding the available “highway” for data: The most direct way Wi-Fi 7 increases speed is by doubling the maximum channel bandwidth from 160 MHz (Wi-Fi 6) to 320 MHz.
• Managing multiple connections simultaneously: Multi-link operation (MLO) allows a multi-link device (MLD) to establish multiple simultaneous links across the 2.4 GHz, 5 GHz and 6 GHz bands.
• Ensuring ultra-reliable delivery for time-sensitive tasks: While standard target wake time (TWT) helps devices save power, restricted TWT (R-TWT) is designed specifically for latency-sensitive applications such as industrial IoT or virtual reality.

By combining 320 MHz channels with MLO and R-TWT, Wi-Fi 7 transitions from being just a “faster” version of Wi-Fi 6 to a standard capable of supporting industrial-grade automation and seamless immersive entertainment.

IEEE 802.11be physical layer

While the IEEE 802.11be PHY layer builds upon the foundation of Wi-Fi 6 (IEEE 802.11ax), it introduces important differentiators. These innovations focus on more flexible spectrum management, enhanced signaling and efficient resource allocation.

• Optimized tone plans and resource units (RU): Wi-Fi 7 maintains the orthogonal frequency division multiple access (OFDMA) introduced in Wi-Fi 6 but refines the tone plans to improve efficiency.
• Multiple resource units (MRU) per user: An important characteristic of Wi-Fi 7 is the ability to assign more than one resource unit to a single user.
• Preamble and subchannel puncturing: Wi-Fi 7 is designed to be a “good neighbor” in crowded unlicensed bands. Preamble puncturing allows a device to utilize a wide channel (like 160 or 320 MHz) even if a portion of that spectrum is occupied by another user.
• Advanced PPDU formats: Data is transmitted via physical layer protocol data units (PPDU), which include a preamble that aids the receiver in synchronization and demodulation. Wi-Fi 7 defines two primary formats: (1) EHT MU PPDU is used for transmissions to one or more users and includes the EHT-SIG field, which provides necessary RU/MRU allocation details. (2) EHT TB PPDU is used by stations to respond to an access point’s trigger frame. It features a longer training field (EHT-STF) to improve uplink reliability.
• The universal signal field (U-SIG): This is the most significant change to the Wi-Fi preamble. The U-SIG contains version-independent bits that allow a receiver to immediately identify the PHY version of a packet. This eliminates the complex algorithms used in legacy Wi-Fi, making it easier for different generations of devices to coexist.

PHY layer test requirements

To support the high speeds and low latency of Wi-Fi 7, IEEE 802.11be defines strict testing requirements for both transmitters and receivers. These tests ensure that devices can handle 320 MHz bandwidths, 4096QAM modulation and the complex synchronization required for multi-user operations.

• Transmitter tests focus on signal quality, spectral efficiency and ensuring that high-power transmissions do not interfere with other users in the unlicensed bands.
• Receiver tests verify that a device can accurately “hear” and decode data under various conditions.

In Wi-Fi 7, multiple stations (STAs) often transmit to an access point (AP) at the same time. For this to work, their signals must arrive at the AP perfectly synchronized in time, frequency and power. Trigger-based (TB) PPDU precorrection tests ensure proper precorrection of STA transmissions to meet this goal.

Smart testing for extremely high throughput

Rohde & Schwarz offers an extensive wireless test portfolio designed to support the Wi-Fi 7 ecosystem. Our solutions address the technical demands of IEEE 802.11be, covering the validation of wider bandwidths, complex modulation schemes and innovative features such as MLO. By offering specialized equipment for research labs, design validation, regulatory compliance and high-volume manufacturing, we ensure that next-generation devices can reliably deliver the high throughput and low latency promised by the new standard.