Move over passcodes and fingerprint scanners as researchers have developed wireless biometric earbuds that can unlock your smartphone based on the unique geometry of your ear canals.
The researchers, led by computer scientist Zhanpeng Jin from the University of Buffalo in the US, built the prototype of the tool called EarEcho with a pair of earphones and a tiny microphone.
EarEcho's design was described in the journal Proceedings of the ACM on Interactive, Mobile, Wearable and Ubiquitous Technologies, and the device proved to be roughly 95 per cent effective.
They developed acoustic signal processing techniques to limit noise interference, and models to share information between EarEcho's components.
The device authenticates users based on the unique sound signature that is recorded by its earphone when a sound played into the ear propagates, gets reflected and absorbed by the ear canal.
"It doesn't matter what the sound is, everyone's ears are different and we can show that in the audio recording," said Jin.
He added that the uniqueness of each person's ear canal, capitalised by the device, can lead to a new way of confirming user identity, in a way similar to fingerprinting.
The user's smartphone receives the sound signature from EarEcho via Bluetooth, the study noted.
The new invention was tested in 20 subjects who listened to audio samples in different environments such as the street, in a shopping mall, etc, and with the participants in different positions.
The researchers said that using EarEcho could minimise the need for passcodes, fingerprints, facial recognition, and other biometrics.
According to Jin, the device's greatest potential is in continuously monitoring smartphone users since it is a passive system, unlike active methods such as submitting a fingerprint or using a voice command.
"Just by wearing the earphones, which many people already do, you wouldn't have to do anything to unlock your phone," Jin said.
