It appears that 2022 might be the year WiFi 7, or 802.11be as it’s also known, launches, despite the fact that the specification isn’t set to be ratified until 2024. Broadcom has just unveiled its first set of WiFi 7 radios, as well as accompanying SoC and it looks like the new hardware will bring a big jump in performance under the right circumstances. Broadcom’s first WiFi 7 SoC will be known as the BCM4916, which sports a quad core ARMv8 processor. It appears to be a custom Broadcom design that’s capable of delivering up to 24 DMIPS of performance, but beyond mentioning that it has 1 MB L2 cache and 64 kB L1 cache, Broadcom doesn’t go into any specifics.
The Arm based processor is backed up by what Broadcom calls a Dual Issue Runner Network Processor, or DI-XRDP, which is a packet processor that shuffles the data around between the wired and wireless network interfaces. There’s also a crypto coprocessor and Broadcom has added support for Arm TrustZone and Secure Boot, with the prior having support for a trusted execution environment. What stands out with regards to the BCM4916 compared to most current router SoCs is the wide arrange of high-speed connectivity options. For starters, it has no less than four PCIe interfaces of unspecified generation, as well as a native 10 Gbps network interface and as well as the option for two more. In addition to this, it has a further option for a 2.5 Gbps Ethernet interface, as well as a typical four port Gigabit switch built in. A pair of USB 3.2 ports are also part of the chip, but these are likely to be 5 Gbps ports. The SoC also has support for DDR3 and DDR4 memory.
As for the WiFi 7 chipsets, Broadcom announced five models, the BCM6726 and the BCM67263 for consumer products, the BCM43740 and BCM73720 for enterprise products and the BCM4398 for mobile devices. The BCM6726 is a tri-band radio that supports the 2.4, 5 and 6 GHz bands, whereas the BCM67263 only supports the 6 GHz band. However, the BCM67263 offers 320 MHz channel bandwidth, which is required to reach the claimed 40 Gbps plus bandwidth that WiFi 7 will top out at, but this would require 16 spatial streams. That said, in this case the highest PHY rate is 11.5 Gbps in a four stream configuration. The BCM6726 is limited to 160 MHz channels and as such has half the PHY rate at 5.75 Gbps on the supported bands.
The BCM43740 is something of a combination of the two, as it supports all three bands, as well as 320 Mbps channel bandwidth, whereas the BCM43720 is a two stream product for more affordable devices and as such is limited to a 2.88 Gbps PHY rate using a 160 MHz channel width. Finally the BCM4398 is also a two stream chip, but it supports 320 MHz channel bandwidth and is as such capable of a 6.05 Gbps PHY rate. All of the devices support what Broadcom calls MLO or multi-link operation, which allows for channel aggregation and rapid switching between channels if needed, which could lead to improved performance in high-density WiFi areas. All WiFi 7 radios will also support 4096-QAM modulation, which is four times higher than WiFi 6.
All the products mentioned above are said to be sampling to partners already and some of the companies mentioned in the press release are Asus, Netgear and TP-Link, as well as OEM/ODMs and network operator partners such as Arcadyan, Extreme Networks, Sagemcom, Sercomm and Technicolor. In other words, products should be expected from most players in the WiFi marketspace, potentially before the end of the year.
