應用主動式珈瑪啁啾濾波器組技術於DSP晶片模擬聽障者之耳蝸聽覺機制

Application of Active Gammachirp Filter Banks to Simulate the Auditory Cochlea Mechanism of Hearing Impaired People on the DSP Chip

陳佳賢(Jia-Xian Chen)

指導教授 ： 柯文俊

國立臺灣大學/工學院/工程科學及海洋工程學研究所/碩士(2009年)

https://doi.org/10.6342/NTU.2009.00091

摘要

全球的聽障人士所占的人數已不在少數，大家也漸漸重視起這個議題。早前有聽障人協會及聽障相關的基金會等等來幫助聽障人士，而今有聽障奧運，可見得關於聽障這個議題的重要性。對於聽障人士而言，因為平常沒辦法聽到完整的語音訊號，故常造成學習與溝通上的困難，使我們對聽障人士常會產生誤解。由此可知，若我們想使聽力正常的人能透過某種工具聽到或感受到聽障人士可能聽到的語音，必定更加能去體會到聽障人士由於聽力損失所造成生活與學習上的不便，理解聽障人士其實跟一般人士沒什麼不一樣。也可以因此減少誤解，協助改善其因聽力損失所造成的問題。

由於耳蝸為聽覺系統最重要的部份，故本文的目標為利用數位濾波器組技術來設計耳蝸濾波器組，配合德州儀器所產的浮點式數位訊號處理入門者套件TMS320C6713 DSK(DSP Starter Kit)應用於模擬聽障人士可能聽見的語音。我們會先透過一些期刊或論文來熟悉耳蝸的特性，再利用符合耳蝸特性之珈瑪調濾波器組及主動式珈瑪啁啾濾波器組來模擬各種不同聽障程度損失的耳蝸聽覺機制，最後再利用軟體Matlab及硬體DSP晶片互相配合去驗證及實現聽障者之聽覺，達到能即時(real-time)且方便的目的，使聽力正常的人士能一樣的感受到聽障者的感覺，也能比較明確的知道聽障人士的真正需求為何。

關鍵字

耳蝸 ； 珈瑪調濾波器組 ； 主動式珈瑪啁啾濾波器組 ； 數位訊號處理

並列摘要

It is not a few hearing-impaired people globally and everyone pays greater attention to the subject gradually. There were Chinese National Association of the Deaf and hearing-impaired foundations to help the hearing-impaired people in the earlier days, and now a days the Deaf Olympic shows that the importance of hearing-impaired subject. As regards to the hearing-impaired people, due to being unable to perceive the complete voice signals, they might encounter many difficulties in learning and communication and drive regular people to get misunderstood. Accordingly, supposed a regular people can feel or really hear the voices which hearing-impaired people actually receive through some special instruments or tools, they can really experience some inconvenient problems of learing in life to know the difference between a regular and a hearing-impaired people. Thus mistakes are reduced to get help on improving the problems resulting from hearing-impaired.

Because the cochlea is the most important one of auditory system, this thesis is to design cochlea auditory filter banks by using the principle of digital filter banks to apply on the simulation of the voices actually received by the hearing-impaired people combining with digital signal processor TMS320C6713 DSK produced by Ti. We can first understand the feature of the cochlea by surveying the papers published in some journals involved, then use the gammatone filter bank and active gammachirp filter bank to simulate the different degree of hearing-impaired hearing loss of cochlear mechanisms. Finally we use the Matlab and DSP processor to approve and implement the sense of hearing of hearing-impaired people in real-time and convenient situations. Therefore, the fact as talked can make those people of normal hearing feel the sense of hearing-impaired people and also understand much more what the hearing-impaired people really need.

並列關鍵字

Cochlea ； Gammatone filter bank ； Active Gammachirp filter bank ； Digital Signal Processor

參考文獻

analyzer,” Proceedings of the Royal Society of London.

membrane measurements and the travelling wave,”

Hearing Research, Vol.22 pp.147-153, 1986.

Potentialities and limitations of the reverse

correlation technique,” J. Acoust. Soc. Am., Vol.63