Headphones with Active Noise-cancelling (ANC) work by creating a sound wave, which is 180 degrees out of phase with the ambient sounds that are picked up by its microphones. This method is used by a majority of audio device manufacturers but this could soon change as researchers at the University of Illinois have come up with a new method that uses wireless signals to enable better quality ANC on headphones. Headphones pick up the outside noise via sound waves and produce out-of-phase waves to cancel out outside noises, however, the new research suggests using a microphone to capture the noise and using wireless technology to send it to an earphone so that it can quickly generate opposite soundwaves of better quality. You can read the thesis here.
Romit Roy Choudhury, a professor at University of Illinois told New Atlas, " (using the new technology) Our ear device gets the sound information in advance, and has much more time to produce a better anti-noise signal," As wireless signals travel way faster than sound waves, using a mic for picking up sounds seems like a good application. However, this might not be possible in all scenarios like when a person is walking in the street. The proposed method is said to be more suited for places like an office environment and an example could be cancelling out conversations that are taking place in a user’s vicinity.
Sheng Shen, the lead author of the study, says, "the moment the device hears the sound it is sent out wirelessly." ECE Assistant Professor Haitham Hassanieh, a co-author on the paper says, "This is bound to change the way we think of noise cancellation, where networks of IoT sensors coordinate to enable quieter and more comfortable environments." The research will be presented at the Association for Computing Machinery Special Interest Group on Data Communication (ACM SIGCOMM) Conference this month, which is taking place in Budapest, Hungary.