Researchers at Penn State have developed an AI‑powered system that uses millimetre‑wave radar to capture a phone’s speaker vibrations from up to 10 feet away, translating them into transcripts with roughly 60 % accuracy. The method, combined with OpenAI’s Whisper, could allow criminals or spies to eavesdrop without bugging your phone.
Think your phone calls are safe if nobody’s holding a microphone? Think again. A jaw‑dropping research project reveals that AI can reconstruct private conversations by reading the minuscule vibrations of your phone’s speaker from across the room. It’s like something out of a spy movie – except it works with $10 radar hardware and open‑source software.
How the attack works
According to India Today’s report on the Penn State research:
Millimetre‑wave radar: A low‑power radar sensor beams signals at your phone’s earpiece. As sound waves from a call vibrate the speaker, the radar detects the subtle movements of the phone surface.
AI signal processing: A custom machine‑learning model cleans and amplifies the radar reflections, isolating the vibration pattern corresponding to the speaker’s audio.
Speech recognition: The processed signal is fed into OpenAI’s Whisper, which outputs text transcripts. In tests, the system achieved around 60 % word accuracy at distances up to 3 metres.
This setup can function through walls and doesn’t require physical contact with the target phone. Researchers warn that miniaturised versions could easily be concealed in furniture or lamps.
Engagement signals
Reddit: A post describing the hack on r/technology hit 500+ upvotes in half a day, with commenters likening it to “laser microphone 2.0.”
Twitter/X: Cybersecurity researchers shared the article, garnering 1,200 retweets. Many expressed shock that off‑the‑shelf sensors combined with Whisper could achieve such results.
YouTube: Several tech channels produced explainer videos with a combined 100 k views, warning viewers to be cautious about phone calls in public spaces.
Implications for security and privacy
Consumer devices vulnerable: Any smartphone speaker could be targeted because the system relies on external radar and not on hacking the device itself.
Data exfiltration: Spy agencies or criminals could capture sensitive conversations (banking details, corporate secrets) without leaving digital traces.
Regulation lag: There are currently no laws regulating the use of millimetre‑wave sensors for acoustic spying. Privacy advocates are calling for legislation.
Countermeasures: Experts suggest using call encryption apps that mask sound or physically shielding phones with Faraday cages. Future phones might need acoustic dampening materials to block vibrational leakage.
What researchers say
Lead author Jiahao Guo told India Today that miniaturisation of radar sensors means “wireless bugging of phones may soon become practical”. The team emphasises that the technology is meant to expose vulnerabilities, not enable spying. They hope phone manufacturers will design hardware that reduces vibrational emissions.
What’s next
Expect privacy and security forums to debate regulations on radar‑based eavesdropping. Law enforcement might adopt similar tools to monitor suspects, raising civil liberties questions. Big tech companies could face pressure to redesign phone speakers to prevent such attacks.
FAQs
How far away can radar eavesdropping work?
The Penn State system worked up to 3 metres (about 10 feet) in lab tests.Does the attacker need access to my phone?
No. The method uses external radar to detect vibrations; no hacking of the device is required.What accuracy can be achieved?
The system achieved roughly 60 % word accuracy, which is enough to capture keywords and context.How can I protect myself?
Avoid sharing sensitive information aloud, use encrypted communication apps with noise‑masking features, and be aware of your surroundings.Is this legal?
Laws vary by jurisdiction. In many places, intercepting private communications without consent is illegal, but regulations specific to radar eavesdropping are unclear.
