TY - JOUR
T1 - Cochlear implant filterbank design and optimization
T2 - A simulation study
AU - Cosentino, Stefano
AU - Falk, Tiago H.
AU - McAlpine, David
AU - Marquardt, Torsten
PY - 2014/2
Y1 - 2014/2
N2 - Cochlear implants (CIs) are devices capable of restoring hearing function in profoundly-deaf patients to an acceptable degree of performance. An essential processing step in any cochlear implant is frequency analysis, which is usually performed via banks of filters. Here, we simulate and test the suitability of different filters and filterbank architectures for CIs with respect to their performance in speech intelligibility. Four different filters were implemented in an established model of CI hearing, the tone-excited vocoder, namely: GTF (Gammatone Filter), DAPGF (Differentiated All-Pole GTF), OZGF (One-Zero GTF) and BUTF (Butterworth). Three filterbank parameters, the filter order (N), the filter quality factor (Q) and the number of channels (Ch), and their combinations were tested using objective and subjective metrics. Simulation results show that all filters tested are suitable for CI implementation, but that the choice of and parameter values is crucial. For most conditions, optimal (N, Q) combinations were within few units away from the combination (2, 4).
AB - Cochlear implants (CIs) are devices capable of restoring hearing function in profoundly-deaf patients to an acceptable degree of performance. An essential processing step in any cochlear implant is frequency analysis, which is usually performed via banks of filters. Here, we simulate and test the suitability of different filters and filterbank architectures for CIs with respect to their performance in speech intelligibility. Four different filters were implemented in an established model of CI hearing, the tone-excited vocoder, namely: GTF (Gammatone Filter), DAPGF (Differentiated All-Pole GTF), OZGF (One-Zero GTF) and BUTF (Butterworth). Three filterbank parameters, the filter order (N), the filter quality factor (Q) and the number of channels (Ch), and their combinations were tested using objective and subjective metrics. Simulation results show that all filters tested are suitable for CI implementation, but that the choice of and parameter values is crucial. For most conditions, optimal (N, Q) combinations were within few units away from the combination (2, 4).
UR - http://www.scopus.com/inward/record.url?scp=84897937537&partnerID=8YFLogxK
U2 - 10.1109/TASLP.2013.2290502
DO - 10.1109/TASLP.2013.2290502
M3 - Article
AN - SCOPUS:84897937537
SN - 1558-7916
VL - 22
SP - 347
EP - 353
JO - IEEE Transactions on Audio, Speech and Language Processing
JF - IEEE Transactions on Audio, Speech and Language Processing
IS - 2
ER -