电子耳蜗的小波过零刺激方案及其DSP实现

Presentation and DSP Implementation of Wavelet Zero-cross Stimulation Strategy for Cochlear Implants

目的:介绍小波过零刺激(Wavelet Zero-cross Stimulation,WZS)算法,并利用该算法设计实现人工电子耳蜗系统。方法:基于DSP芯片,采用ICETEK-VC5416语音开发板模拟小波过零刺激语音编码策略,同时进行人工电子耳蜗系统的硬件设计,并将计算机模拟的结果和CIS方案对比。结果:经过小波过零刺激算法处理的8个通道的语音信号进行合成,然后经扬声器播出,可听见较清晰的声音。结论:对小波过零刺激方案于语音信号小波变换域的过零点处合成刺激脉冲,其保留了语音信号的时域相关性和相干性,能够反映人的耳蜗对语音信号的时间编码特性。

Objective To introduce the wavelet zero-cross stimulation algorithm and based on which to design and implement the cochlear implants. Mothods Through DSP and ICETEK-VC5416, the WZS speech coding strategy was simulated, and also the presented WZS strategy was compared to CIS strategy by hardware implementation and computer simulation. Results The processed audio signals, output from eight channels, were synthesized and played through loudhailer and could be heard with high fidelity. Conelusion The wavelet zero-cross stimulation（WZS） strategy, which generates stimulating pulsatile series at zero-cross points in the domain of wavelet transform, can keep the temporal correlation and coherence of speech remained in stimulating pulsatile series and reflects the characteristic of temporal coding for cochlea.[Chinese Medical Equipment Journal,2008,29 （11 ） ： 1-4]