基于最大平坦分数延迟的电子耳蜗信号采集

Maxflat-based fractional delay in signal acquisition for cochlear implants

麦克风阵列的方法逐渐应用于电子耳蜗前端语音增强中,其中,延迟波束形成技术由于其计算量低,适用于电子耳蜗双麦克风信号采集。延迟是波束形成方法里的一种重要参数,而在电子耳蜗小间距的应用场景中会存在分数延时的问题。结合电子耳蜗滤波器组中实际的频率分布特性,本文探讨了基于最大平坦准则设计的分数延时滤波器的特征,并分析了其参数变化特性,有助于构建具有实用价值的电子耳蜗前端延时波束形成算法。

Microphone array-based methods have been applied in the front-end speech enhancement for cochlear implants.In array-based methods,delay and beamforming technology,with its low computation complexity,is suitable for dual microphone signal acquisition of the cochlear implants.Delay is an important parameter in beamforming method,and the small intermicrophone in the cochlear implant results in the problem of fractional delay.By considering the actual frequency distribution feature of the filter bank in cochlear implants,we explored the characteristics of Maxflat-based fractional delay filter and analyzed the features of the parameter variations,which may help to construct practical front-end delay beamforming algorithms for cochlear implants.