An evaluation of hearing-aid array processing

Among the array-processing techniques that have been proposed for hearing aids are classical delay-and-sum beamforming, superdirective arrays, and adaptive arrays. In order to directly compare the effectiveness of the different processing strategies, a 10-cm long linear array was built using five uniformly-spaced omnidirectional microphones. This array was used to acquire speech and noise signals for array placements in a representative room. The processing comparison indicates that a superdirective array is an effective processing strategy, and that the performance of adaptive arrays may not justify the additional system complexity.