What Broadcom’s latest Wi-Fi 7 chips tell us about the IoT

This story was originally published on June 23, 2023 in my weekly IoT newsletter. You can sign up here.

Broadcom’s claim to fame before it became a chip and software conglomerate was that it was able to integrate multiple radios on a single chip. This integration led to energy and cost savings and propelled the adoption of multi-radio technologies into more devices. After all, if a hardware designer could easily put Wi-Fi and Bluetooth in their device, why not add both?

Broadcom’s newest generation of Wi-Fi 7 chips embraces its past by integrating three radio options for both enterprise and consumer use cases. And those use cases are all about the IoT. So with Broadcom now delivering the future of the connected home, warehouse, car, and store with these chips, what does that future look like?

Of the three new Wi-Fi 7 chips launched this week, I care about two. The first is the BCM47722, which is designed for enterprise access points. These are the devices you see on the ceilings of offices, stores, and hotels that provide Wi-Fi access. This chip combines the latest version of Wi-Fi that supports the older 2.4 GHz and 5 GHz bands as well as the newer 6 GHz band. It also adds more capacity, doubling the channel size over which the chip can send data.

But for the IoT, the excitement is in the integrations. Broadcom has integrated two additional radios capable of supporting Bluetooth and the 802.15.4 protocol, which both Thread and Zigbee use. That means it could be used to support Matter as well. As Mike Powell, director of product marketing, wireless communications and connectivity at Broadcom, noted, Bluetooth has been in use in the enterprise for years, but new use cases for Bluetooth and 15.4 radios led Broadcom to add the new functionality.

On the Bluetooth side, the rise of electronic shelf labels means that the density of Bluetooth devices in places like retail stores will increase exponentially, while adoption of Zigbee lighting or Matter functionality in offices or hotels will drive demand for those radios. According to Powell, the new chips can support thousands of Bluetooth devices, which is great for both asset tracking and electronic shelf labels.

Additionally, with Wi-Fi 7, the standard gets something called multi-link operation (MLO), which will help deal with latency caused by congestion and interference. MLO enables the Wi-Fi device to monitor the quality of two different channels and hop back and forth between them as needed. It’s akin to weaving in between lanes of traffic so you can keep plowing ahead. With all of the devices — and more crowded airwaves (the 2.4 GHz band is home to Wi-Fi, BLE and 802.15.4) — tweaks like MLO will help keep data packets moving.

The second chip I care about is the BCM4390, which combines all three radios (Wi-Fi, BLE, and 802.15.4) and is designed for handsets and tablets. That’s right, this silicon will bring Zigbee and Thread to phones and tablets.

Adding Zigbee or Thread to a handset may not make much sense because phones move in and out of a home or office based on the person carrying it. They won’t make great hub devices for managing lights or a good Thread border router sitting stable at home controlling other devices, but you might want them on a handset to provision a new smart home product.

But using this chip in a tablet makes more sense. I’d love a home tablet that could act as a mobile smart home controller and display, and with the Zigbee/Thread radio it could become a lynchpin in a Matter-enabled home.

The bigger value is associated with the economies of scale that widespread adoption of such a chip could provide. If this chip gets added into phones it becomes cheaper to produce and buy. With this chip we could see an iPad that acts as a Matter controller or a Pixel tablet that plays a dual role as a tablet and smart home display. Gabriel Desjardins, director of product marketing, wireless communications and connectivity at Broadcom, told me he expects the handset-focused chips to hit end devices in 2025.

Finally, both chips are going to support the latest Bluetooth 5.4 standard along with a potential Bluetooth security feature called Bluetooth Channel Sounding. The draft version of the Channel Sounding proposal makes Bluetooth better at fine-grained location tracking, which means Bluetooth devices could wait until they are close to a device before sharing data. The Channel Sounding is part of the draft of the 5.4 Bluetooth specification expected some time in the first half of 2024.

Fine-grained location is essential when it comes to using BLE for replacing car key fobs with a smartphone, and even for better asset tracking. Today some BLE transmissions can be scanned by anyone located nearby, who can then steal the data. Such attacks could allow criminals to steal cars using Bluetooth fobs. With asset tracking, better location simply means that instead of getting within a few feet of a missing object, you can get within inches.

Ultrawideband radios are currently doing a good job of fine-grained location tracking, but Broadcom and the Bluetooth SIG are betting on more options being better. They’re probably right.

Right now, the IoT has many different radios and options available for different use cases. With these chips, Broadcom is confirming that many of them, such as connected building systems and asset tracking, have become standardized, while also anticipating the success of Matter and with it, the ability to use our phones as car keys.