Abstract: Cochlear implantation is a new technology to restore the hearing ability for deaf people. A new type of digital filter with better filtrating ability, that is an all phase DFT filter, was introduced to simulate cochlear implantation CIS speech processing and to synthesize the voice, using the simple model of electrode excitation cochlear implant. By doing this, the voice can be simulated for the person with a cochlear implant. Comparisons between this model and the traditional Butterworth filter were made. The results of the experiment show that the synthesized speech spectra by the all phase DFT digital filter is closer to the original speech spectra, and is much better than the results of the Butterworth filter.

Key words: the all phase DFT filter, continuous interleaved sampler (CIS) , cochlear implant