Question

Write a few sentences stating the problem that you intend to address or solve. The problem must be clear and well founded/backed by reference/s. Something mechanical engineering related or electrical

Answer 1

(Electrical engineering- signals and system + communication systems)

I want to solve the problem of background noise in mobile phones. When we talk during a phone call, the background noise(due to say loudspeakers playing in the background, or traffic on road) makes it difficult for person on the other side of the phone to hear me. The existing noise cancellation technology in smartphone comprises of two microphones(one in front and one at the back of the phone). The front microphone (which is nearer to our mouth) gets higher percentage of our voice, while the microphone at the back gets less of our voice and contains the more general noise. The signals from these two sources are subtracted, so the noises get cancelled. But this method is not at all accurate. Since the two microphones are separated at a distance from each other, both receive signals at different times(as the signals reach both microphones at different times). Hence noise is never really cancelled. There should be a way to spot the talker' mouth and take input only from that direction, and suppress signals coming from any other source.

Reference-> E. Mabande, F. Kuech, A. Niederleitner and A. Lombard, "Towards robust close-talking microphone arrays for noise reduction in mobile phones," 2016 IEEE International Conference on Acoustics, Speech and Signal Processing (ICASSP), Shanghai, 2016, pp. 3181-3185.