Rooman Sapienza-yliopiston tutkijat ovat kehittäneet WhoFi-järjestelmän, joka kykenee tunnistamaan ihmiset ilman kameraa pelkästään Wi-Fi-signaalien avulla. Ratkaisu hyödyntää langattomien reitittimien tuottamaa Channel State Information (CSI) -dataa, joka sisältää yksilöllisiä piirteitä ihmisen kehon rakenteesta, liikkeistä ja jopa sisäisestä koostumuksesta.

Käytännössä Wi-Fi-signaalin kulku vääristyy eri tavoin riippuen siitä, kuka sen tiellä liikkuu – ja tämä vääristymä toimii henkilön ainutlaatuisena “radio­biometrisena allekirjoituksena”.

Wi-Fi security usually means keeping virtual intruders off your network, but a new system claims to be able to use Wi-Fi networks to detect physical intruders. Gamgee’s Wi-Fi Home Alarm System can learn to recognize people and pets who belong there and alert you to strangers – or perhaps even when an elderly person takes a fall

What is Wi-Fi Sensing?

Wi-Fi Sensing technology harnesses Wi-Fi signals to sense activities and interpret movement. The technology applies AI capabilities to make sense of Wi-Fi signals, called “channel state information (CSI),” to perform the sensing. Some sensing capabilities include basic motion detection, motion localization, presence detection, speed/velocity measurement, breathing detection, sleep monitoring, and daily activity monitoring.

How does Wi-Fi Sensing work?

Wi-Fi Sensing uses the Wi-Fi signals that exist in a home or building. Much like a pool of water waves, when a person or object crosses the pool of radio waves of a wireless device or other Wi-Fi-enabled IoT devices, Wi-Fi Sensing technology can sense the disruption and use the information to determine the size, speed, and location of the disruption.

The 802.11bf Wi-Fi standard provides a set of back-and-forth signaling protocols to set up Wi-Fi stations that, if done right, can be used to establish a Wi-Fi Sensing network. It turns out that every time a data packet is sent over the air via Wi-Fi, the Wi-Fi devices compute CSI of the wireless channel to overcome interference from the environment so as to decode the data packet properly.

While the CSI is designed primarily for data communication, in recent years we discovered that to overcome the interference due to the surrounding object movements and changes, the CSI actually captures a huge amount of information of the environment. So, in a nutshell, we perform Wi-Fi sensing by “decoding” the information hidden in the CSI. Companies like Origin apply AI on the CSI to achieve a vast array of sensing tasks.