Researchers from the University of Chicago launched a pilot bracelet, which with the help of 24 speaker generated noise in the ultrasonic frequency range to suppress most microphones, regardless of their orientation.
This gadget uses a non-linear distortion built-in amplifier for “leaking” ultrasonic noise in the audio range, thereby eliminating the possibility of recording the conversation.
Such an unusual bracelet design is not a fad. It not only generates omnidirectional interference, but also allows you to eliminate blind spots (when the transducers suppress each other) when moving the wrist. As a result, the bracelet is even more efficient than a dedicated fixed attenuators, and can even suppress the hidden microphones.
Ultrasound is imperceptible to others, except, perhaps, young people and dogs, but for all nearby microphones will detect only the high frequency noise instead of other sounds.
This gadget can be useful for owners of smart devices like smart speakers, calls and the like almost always included microphone. According to statistics, one in five American adults owns a smart speaker, but the Network has appeared record conversations, “listening” and recorded with smart devices.