Signal processing algorithms for an open-platform DSP hearing aid
Brent Edwards, John L. Melanson, Nikolai Bisgaard · The Journal of the Acoustical Society of America · 1999
The development of DSP chips that meet the small-size and low-power constraints of hearing aids has increased the signal processing capabilities of such devices tremendously. Processing schemes that would be difficult, if not impossible, to implement on an analog chip can easily be implemented digitally. These signal processing algorithms for hearing aids can be classified into one of three categories: those intended to restore impaired hearing to normal, those designed to improve speech intelligibility in noisy situations, and those that improve the functionality of the device. The signal processing algorithms for an open-platform, or software-based, DSP hearing aid will be discussed, with an emphasis on features that are unique to this device. These include FFT-based multiband compression, active feedback cancellation, and digitally processed multi-microphone directionality. The perceptual benefits associated with each algorithm will be provided.