Efficient Real-Time Acoustic Feedback Cancellation using Adaptive Noise Injection Algorithm

Acoustic feedback cancellation is a challenging problem in the design of sound reinforcement systems, hearing aids, etc. Acoustic feedback is inevitable when the acoustic signal path forms a loop between the microphone and loudspeaker. An efficient short duration noise injection algorithm is proposed in this paper to estimate the impulse response of the acoustic feedback path model. The algorithm does not require any prior information about the acoustic feedback path. It is capable of optimally estimate the acoustic feedback path for cancellation, and avoid the occurrence of any howling episode, in varying acoustic environments. Presented algorithm is efficiently implemented on smartphone device having close proximity of loudspeaker and microphone to emulate the feedback condition. The algorithm being platform-independent can also be implemented for any set-up or system. The experimental results of the proposed method shows satisfying results and its ability to track and cancel the acoustic feedback in changing characteristics of the acoustic path.