Sometime in 2024, the IEEE will unveil a new 802.11 standard that will bring new capabilities to everyone’s favorite wireless communication standard. But the upcoming 802.11bf standard isn’t for communication — it’s for sensing.
The newest version of Wi-Fi layers on the ability to sense people or objects by using math to calculate how they disturb the signals bouncing around a physical space, so our established Wi-Fi devices will become part of a network that will be used to figure out the location of humans and things contained within particular spaces. It will also be the first time we’ll have a version of Wi-Fi that goes beyond data transmission. In other words, it’s a pretty big deal.
A proto version of the technology is currently being used to detect motion in certain smart home applications, thanks to a company called Cognitive Systems. But standardization will make Wi-Fi sensing ubiquitous. So it’s worth learning a bit about what it can and can’t do, and how product companies might layer it into their devices.
The IEEE plans to take the concepts for Wi-Fi sensing from the proprietary system built by Cognitive (which has been licensed to Qualcomm and also Plume) and create a standard interface for how the chips calculate interference that determines where in space an object is.
Because the primary focus of Wi-Fi is sending packets of data, it’s important that Wi-Fi sensing doesn’t interfere with that job. To that end, Wi-Fi sensing will be leveraging the orthogonal frequency-division multiplexing (OFDM) waveforms used by communication technologies. So it will take a little extra math to calculate spatial interference.
And that means Wi-Fi sensing isn’t going to be super granular, nor will it be ideal for measuring velocity. (The next story looks at alternatives for handling velocity.) But we will be able to use Wi-Fi sensing for basic motion detection, such as tracking the flow of people in rooms. We’ll also be able to combine it with other sensors for even more interesting applications.
The proposed standard does look at using 60 GHz spectrum for fine-grained motion sensing, but that would require new gear. Today’s Wi-Fi devices rely on the airwaves at 2.4 GHz and 5 GHz.
According to Geordie Hagerman, EVP of Commercialization with Cognitive, Wi-Fi sensing offers 99.999% accuracy when it comes to motion detection and about 90% accuracy when it comes to figuring out where items are in a room. The plan is that once basic motion detection is standardized companies could fine-tune algorithms to label the types of motion a person might make. That means something like fall detection could become possible using Wi-Fi devices spread around a room. (Wi-Fi sensing currently uses software on Wi-Fi devices — three devices in a room provides good coverage — to paint a picture of the objects and people in a room.)
Right now, each device has to have Cognitive’s software on it, but 802.11bf will result in software that any device can run so it can become part of a network of Wi-Fi sensors. I’m excited about Wi-Fi sensing’s potential for the smart home, but it will also be useful for the enterprise and even retail environments.
That said, it’s still a ways off. The IEEE took up discussion of the standard and created a working group dedicated to it last fall, and the finalized specification isn’t expected for another three years. The nice thing is that companies are already playing with Wi-Fi sensing, so when the formal standard arrives we’ll already have a lot of ideas ready for how to use it.
In other words, get those product roadmaps ready!