Broadcom launches Wi-Fi 7 wallet for access points and client devices

The past few years have seen a growing consumer focus on wireless networks. The industry has also been very busy, allowing Wi-Fi 6 (802.11ax) to operate in the 6 GHz band with Wi-Fi 6E. In parallel, the 802.11 working group began work on 802.11be with a focus on Extremely High Throughput (EHT). Wi-Fi 7 is set to become the consumer-facing moniker for 802.11be.

802.11be aims to achieve high throughput primarily through a combination of three aspects:

  • Support up to 16 spatial streams
  • Support for channels 320MHz wide (operating in the 2.4GHz, 5GHz, and 6GHz bands)
  • 4096-QAM (4K-QAM) support resulting in better use of available spectrum (faster modulation/encoding scheme).

In theory, these aspects allow up to about 46 Gbps of wireless throughput. 802.11be also aims to enable the use of Wi-Fi for real-time applications by including features for low-latency communications such as multi-link operation (MLO). This allows the client and the access point to communicate simultaneously over multiple channels that may even belong to different domains. Interference and coexistence with non-Wi-Fi users of the same spectrum is handled using Automatic Frequency Format (AFC).

A number of additional features targeting these two payment areas are under consideration for the final standard. However, many silicon vendors have already begun to provide silicon supports for aspects listed in the first draft 802.11be specification.

Mediatek was one of the first vendors to demonstrate 802.11be compliant silicon work earlier this year. Although Mediatek has indicated that the products will be marketed within the Filogic lineup, concrete technical details and part numbers have not been announced. At MWC 2022, Qualcomm provided details of the 802.11be client silicon targeting mobile devices. The FastConnect 7800 is expected to be available in H2 2022, and it integrates Bluetooth 5.3 support with key Wi-Fi 7 features.

Broadcom Corporation is announcing a comprehensive range of products targeting the diverse Wi-Fi 7 markets today.

The table below summarizes the main features of products targeting access points. All of these support 4K-QAM and Multi-Link.

Broadcom 802.11be (Wi-Fi) Access Point Radio Specifications
BCM67263 BCM6726 BCMN43740 BCMN43720
target market Residential Wi-Fi Hotspots Enterprise Wi-Fi Hotspots
operational band 6 GHz 2.4 GHz (or) 5 GHz (or) 6 GHz
stream number 4 2
the above. Channel View 320 MHz 160 MHz 320 MHz 160 MHz
PHY rate 11.5 Gbps 5.75 Gbps 11.5 Gbps 2.88 Gbps

AP products support AFC to ensure that the 6 GHz band is not affected (access points are authorized to receive regularly scheduled authorization from a central authority to prevent interference with users of the 6 GHz spectrum). Broadcom has applied to become an AFC operator and will provide AFC with its chips. This will use Open AFC code. Broadcom also believes that the vibrant Wi-Fi 7 system requires an AFC service that device makers can use independently of the chip vendor. Organizations such as the Wi-Fi Alliance and Wireless Broadband Alliance have stepped in to act as AFC operators, with Open AFC already gaining momentum in the field.

Linking them together in the Broadcom Wi-Fi 7 router’s reference design is the BCM4916 network processor. ARM v8-compatible quad-core SoC includes a dual-version Runner Packet processor (DI-XRDP), NBASE-T (up to 10Gb) Ethernet PHY for WAN or LAN, four onboard 1GbE PHYs, three USXGMII interfaces, multiple USB ports, And a 32-bit DDR3/DDR4 DRAM interface.

The quad-core CPU is a Broadcom custom design with 64KB level 1 cache and 1MB level 2 cache, delivering up to 24KB DMIPS power. Without knowing the exact clock speeds, it’s hard to compare with standard ARM Cortex cores. Based on the DMIPS number, this appears to fall between the Cortex-A53 and the A57, but it doesn’t include the ARM v8.2 features of the A55.

Broadcom customers can play with the radio configuration in the above design to create products at different price points. Triple band support becomes mandatory in Wi-Fi 7. The very high throughput enabled by this means that 10G support on the WAN/LAN side and NBASE-T support on the LAN interface will become the de facto standard for routers and access points in the coming years.

Broadcom also offers the BCM4398 – an integrated Wi-Fi 7 and Bluetooth 5 combined chip aimed at smartphones and other mobile applications. It supports two streams of Wi-Fi 7, channel width up to 320MHz, and a PHY rate of 6.05Gbps. On the client side, one of the major updates visible to the user is low latency. Broadcom claims that the BCM4398 can achieve sub-millisecond latencies for slightly crowded environments in the 6GHz band. The client’s multi-link triggering feature can keep the uplink and downlink latency between 5 and 10 milliseconds in situations where both the 5 and 6 GHz bands are heavily congested. This provides an imperative for AR/VR knowing that the worst latency will drop to a few milliseconds even during heavy crowds.

Broadcom is the first vendor to announce a full line of Wi-Fi 7 products, with sampling for major customers already in the pipeline. New products should give end consumers a taste of the values ​​that Wi-Fi 7 offers for different applications a few quarters from now.