Application of Digital Signal Processor for the Nucleus 22 Channel Cochlear Implant System

Abstract

Nucleus 22 channel cochlear implant system extracts features with an analog electric circuit. We replaced analog with digital processing and devised an acoustic simulator to evaluate the system. Our system consists of three parts, a DSP (Digital Signal Processor) board, a BCG (Burst Code Generator) and an acoustic simulator. The DSP board is not only a replacement of the analog circuit with a digital signal processor TMS32010, but provides also many other possibilities of advanced processing algorithms. The BCG was realized a fully compatible interface with the conventional implant system, so the implanted receiver-electrode units can be arbitrarily controlled from the DSP. The acoustic simulator represents the psychological effects for the subject wearing the implant system which excites the characteristic frequency resonator by the stimulus pulse for each channel. The design of our system is described in this paper.