Subband signal processing for hearing aids

In this paper a hearing aid concept working in subbands is presented. Consideration is given to the compensator for recruitment of loudness and the acoustic feedback cancellation. In addition, a step-size control for fast tracking and a constant error level with non-stationary input signals is presented. The feedback canceler is adapted to the feedback path in the transform domain using a power-normalized least mean square (LMS) algorithm. The transformation into subbands is based on the modulated lapped transform (MLT). Together with the feedback canceler the proposed hearing-loss compensating forward filter is computationally very efficient.