Anti-AI Eavesdropping White Noise Office HushSpace Deployed: Stopping Employee Conversations from Being Captured by Smart Speakers

HushSpace, released by the Fraunhofer Institute for Applied Information Technology, is an environmental privacy protection solution that uses white noise interference to keep AI smart speakers from capturing conversations in office areas. The system uses a set of micro speakers installed on the ceiling of the office area, emitting specially modulated white noise that is almost imperceptible to the human ear but can interfere with smart speaker microphone arrays.

The design principle of HushSpace leverages the difference in frequency sensitivity between the human ear and microphones. The human ear is insensitive to ultrasound above 15 kHz, but consumer-grade smart speaker microphones can effectively receive it. HushSpace emits carefully modulated ultrasonic white noise, causing severe interference with smart speaker voice recognition while having almost zero impact on normal conversation among office workers.

The pilot was conducted at two tech companies in Munich, Germany. HushSpace was deployed across 2,800 square meters of office space at the two companies. Three months of operating data show that the proportion of office conversations mistakenly woken up and uploaded to the cloud by smart speakers dropped from a baseline of 14 percent to 0.3 percent. Professor Christoph Busch, who heads the digital privacy department at the Fraunhofer Institute, said this kind of physical-layer privacy protection is more reliable than software-only solutions such as local processing. HushSpace will be offered to enterprises on a rental basis at 2.4 euros per square meter per month.