American engineers created a bracelet to protect the owner from wiretapping

A group of engineers from the University of Chicago have developed a prototype bracelet that prevents voice assistants from listening to conversations and recognizing speech.

The solid white bracelet is equipped with 23 ultrasonic transmitters, and a microprocessor, a signal generator, and a battery are installed inside. You can activate the device using the switch on the housing. During the operation of the device, the transmitters emit ultrasound with a frequency of 24 to 26 kilohertz, which are distributed throughout the room.

When this sound hits a working microphone, it is converted to sound, overcoming the ultrasonic frequency filter, which is usually equipped with microphones from smartphones, smart speakers and other gadgets. Thus, a working bracelet creates a loud noise for microphones, which does not allow you to pick up and recognize speech.

The engineers tested the bracelet by comparing the results of voice recognition from a smartphone and an IBM service with the bracelet on and off. Tests have shown that with the bracelet turned off, the probability of word-for-word error is around 30% and when it is on, it increases to 97%. To demonstrate the capabilities of the device, the scientists made a short video.

It is not the first development of this type. Last January, Danish engineers Björn Karmann and Tore Knudsen created a special 3D printed nozzle for smart speakers, which is a kind of socket for the built-in microphone. Externally, a device called Alias looks like a frozen foam hat, and its essence is that the column does not exactly hear the owner in standby mode.

Source: Websites