A New Speech Coding for Improving the Quality of Cochlear Implant

Cochlear implant is a sort of equipment which is used to restore normal hearing to the profoundly deaf by electrical stimulation of the auditory nerve. And it is an imitation of normal hearing function. However ,the speech signal coding methods used in the cochlear implant at present consider only about the conversion from speech signal to electrical signal, without the function of human cochlear\´s temporal encoding pattern. So the effect of the cochlear implant is not very perfect. This paper combined the mechanism of hearing physiology, presented a new solution which generated stimulating pulsatile series by a "Amplitude-Time-Frequency" method. The coding method is converting the speech signal\´s amplitude into stimulating pulsatile series\´s amplitude^ time and frequency. We named it as "ATF coding method". ATF coding method can solve the problem that stimulating pulsatile series\´s dynamic configuration used in the auditory neural center. ATF can keep the temporal correlation and coherence of speech remained in stimulating pulsatile series.