PrivacyMic can capture information inside the home without recording conversations

Engineers at the University of Michigan have created a new device called PrivacyMic that could usher in an era of smart speakers that can capture information inside the home without recording speech. The challenge with smart speakers for many people today is that the microphones are constantly listening for their activation word, so they hear everything that goes on inside the home. PrivacyMic, on the other hand, can listen for the signal that would turn on the smart speaker without eavesdropping on conversations.

PrivacyMic picks up ultrasonic sound frequencies above the range of human hearing. Researchers say that many common household sounds, including dishwashers, computer monitors, and even the snap of your fingers, all generate sounds in the ultrasonic range with a frequency of 20 kilohertz or higher. Human ears are unable to hear the sounds, but the sounds can be heard by dogs, cats, and the PrivacyMic.

The device is designed to gather ultrasonic information around the user to identify when it's needed. In testing, researchers have demonstrated that PrivacyMic can identify household and office activities with more than 95 percent accuracy. University of Michigan associate professor of electrical engineering and computer science, Alanson Sample, says that there are many situations where you want home automation systems and smart speakers to understand what's happening in the home. However, we typically don't want them listening in on our conversations.

Sample says that the team is found you can have a system that understands what's going on with an absolute guarantee it doesn't record any audible information. PrivacyMic filters out audible information directly on the device, making it more secure than encryption and other security methods that seek to secure audio data recorded after the fact. With PrivacyMic, audible information doesn't exist. It's unclear when or if this technology will make it into the commercial market.