Ultrasonic jammers cover up the sound field projected around

Make sure there are no microphones in the room before the discussion, and it is no longer limited to spy movies. The great success of the connected property gives everyone the opportunity to worry about eavesdropping on private conversations. A Bloomberg survey has aroused legal attention and found that all spokespersons using Amazon Alexa virtual assistants inadvertently heard the voices of company employees.

If they were fitted with thick bracelets designed by researchers at the University of Chicago, this would not happen. It is covered by an ultrasonic speaker, and a sound wave field is projected around the wearer. People cannot hear it, but it disturbs the nearby microphone. According to reports, Amazon employees did not record the conversation, but heard white noise.

Today, there are some ultrasonic portable jammer that work on the same principle, but are only effective for the microphones that have been identified, because ultrasonic waves tend to move in one direction. The speakers on the wristband are subject to the same restrictions: for this reason, the researchers placed them everywhere so that they could transmit radio waves 360 degrees. For the same reason, they designed a scrambler that can be worn on the wrist. Since we often speak with our hands, ultrasound waves will spread more, thus maximizing its effectiveness. The researchers said: “Despite the interest in connected speakers, consumers have become more cautious when listening and recording personal conversations. Therefore, it is important to develop tools to prevent microphone abuse.”