Improving channel selection of sound coding algorithms in cochlear implants
Hussnain Ali, Feng Hong, John H. L. Hansen, Emily A. Tobey · 2014
Spectral maxima sound coding algorithms, for example n-of-m strategies, used in commercial cochlear implant devices rely on selecting channels with the highest energy in each frequency band. This technique works well in quiet, but is inherently problematic in noisy conditions when noise dominates the target, and noise-dominant channels are mistakenly selected for stimulation. A new channel selection criterion is proposed to addresses this shortcoming which adaptively assigns weights to each time-frequency unit based on the formant location of speech and instantaneous signal to noise ratio. The performance of the proposed technique is evaluated acutely with three cochlear implant users in different noise scenarios. Results indicate that the proposed technique improves speech intelligibility and perception quality, particularly at low signal-to-noise ratio. Significance of the proposed technique lies in its ability to be integrated with the existing sound coding framework employed within commercial cochlear implant processors, making it easier to adapt for resource-limited and time critical devices.