Small-Space Microphone Array Fractional Delay Algorithm Based on FIR Filter for Cochlear Implant  

作　　者：陈又圣 宫琴 

机构地区：[1]Department of Biomedical Engineering,Tsinghua University

出　　处：《Tsinghua Science and Technology》2011年第1期90-94,共5页清华大学学报（自然科学版（英文版）

基　　金：Supported by the National Natural Science Foundation of China(Nos. 60871083 and 30800234);the Beijing Natural Science Foundation(No. 3082012);the Key Technologies R&D Program of Ministry of Science and Technology of the People’s Republic of China(No. 2008BAI50B08)

摘　　要：Directional speech enhancement of signals from microphone arrays is an effective way to improve speech recognition for cochlear implant users. The strict implant size limitation results in a short distance between microphones. The fractional delay problem due to the short distance between microphones is solved by a maximal flat （Maxflat） finite impulse response （FIR） filter, using the Maxflat error criteria at a low frequency containing most of the speech information and energy. The fractional Maxfiat FIR filter approximates the ideal digital fractional filter at the magnitude response, phase response, and phase delay characteristics, and is also very low order. The results demonstrate that the Maxflat FIR filter accurately and effectively solves the fractional digital delay and is very suitable for real-time speech processing in practical cochlear implant products.Directional speech enhancement of signals from microphone arrays is an effective way to improve speech recognition for cochlear implant users. The strict implant size limitation results in a short distance between microphones. The fractional delay problem due to the short distance between microphones is solved by a maximal flat （Maxflat） finite impulse response （FIR） filter, using the Maxflat error criteria at a low frequency containing most of the speech information and energy. The fractional Maxfiat FIR filter approximates the ideal digital fractional filter at the magnitude response, phase response, and phase delay characteristics, and is also very low order. The results demonstrate that the Maxflat FIR filter accurately and effectively solves the fractional digital delay and is very suitable for real-time speech processing in practical cochlear implant products.

关 键 词：microphone array fractional delay Maxflat FIR filter directional speech enhancement system 

分 类 号：TN64[电子电信—电路与系统]