Feb 20, 2020 15:00:00

A `` bracelet-type eavesdropper '' that prevents everyday conversations from being eavesdropped by smart speakers is developed

It has been reported frequently that smart speakers equipped with voice recognition assistants were ``

recording people's conversations ' ', but we want to avoid listening to private conversations even though it is to improve the accuracy of voice assistants Thing. In order to prevent eavesdropping by such electronic devices and hidden microphones, a research team at the University of Chicago has developed a 'Eavesdropping Jammer that can be worn on the wrist like a bracelet'.

Wearable Microphone Jamming
http://sandlab.cs.uchicago.edu/jammer/

'Consumers are nervous about the fact that interactive devices may always listen, record and store sensitive personal information by default,' the research team said. He says that in the age of voice-based smart devices, it is important to build tools that protect users from potential privacy violations and misuse by microphones. The research team has developed a device that uses 'ultrasonic waves inaudible to the human ear' to prevent eavesdropping by microphones.

You can see how the bracelet type eavesdropper actually works by looking at the following movie.

Wearable Microphone Jamming-YouTube

Men and women pointed at the camera are having a conversation about some research.

When a man asks a question, the woman says, 'This is confidential' ...

I pressed the switch of the machine I put in my left hand.

Then, suddenly, I heard a sound flowing from the news video when the typhoon 'Zar' hit directly, and I could not hear the conversation between the two people.

A bracelet-type eavesdropper put on the left hand is using ultrasound to block the microphone.

The eavesdropper jams not only the microphone of the camera, but also all electronic devices equipped with a microphone, such as smart speakers on a nearby desk, a smartphone in a male breast pocket, and a mounted smart speaker. I am doing.

The bracelet type eavesdropper has a number of speakers facing outward, and it is transmitting ultrasonic waves for interference over a wide range.

The eavesdropper has a built-in controller, signal generator, lithium battery, voltage regulator and amplifier.

What the eavesdropper is transmitting is ultrasonic waves of 24kHz to 26kHz ...

It cannot be heard by human ears.

However, commercially available microphones leak this white noise into the audible range due to the nonlinear characteristics inherent to the hardware. As a result, conversations recorded by the microphone are erased by white noise, which can prevent eavesdropping.

An eavesdropper with loudspeakers facing in multiple directions can block hidden eavesdroppers even in a fixed state, but ...

By moving the eavesdropper, you can reduce the blind spot where the microphone passes through the ultrasound.

Therefore, by attaching the eavesdropper to the bracelet and attaching it to the wrist, the effect of the eavesdropper can be enhanced in conjunction with the body language.