助聽器的目地在於幫助聽障者更容易接收聲音，基本原理就是將各頻率成分個別做不同的放大及設定，以增強聽者的語音辨別能力。但事實上許多患者不願戴助聽器或對助聽器不滿意最大的原因之一，就是覺得很吵，聽到了一些不該被放大的環境雜訊聲音。因此，若要避免使用者感到不舒適，可以有兩種方法，方法一是將助聽器的最後輸出功率調整在不舒適響度值之下，這樣就不會傷害剩餘的聽力;方法二則是設法去增強語音訊號的部分，也就是放大語音且抑制雜訊。本論文為了避免使用者在吵雜環境裡感到不舒適，利用聽覺遮蔽效應的概念來做語音增強，並且以等效矩形頻寬的分頻法及圓通化指數模型描述人耳聽覺上的特性，進而求取聽覺遮蔽門檻值，期望能夠依人耳聽力受損程度進行不同的增強演算。最後對於增強後的訊號，再以梳狀濾波器加強母音的諧波結構，使得原先被破壞掉的較高頻成分訊號能夠重新保留住，並且在噪音環境下對聽障者提供最大幫助。
　　實驗分為客觀評量和主觀評量兩部分，客觀評量評估SNR-改進、頻譜失真量測、Itakura-Saito距離評估。主觀評量評估訊號增強前後聽者的語音辨識能力，測驗者分為正常者及聽障者。實驗結果顯示，對於正常者改善效果不大，但對於聽障者辨識正確率則有一定程度成長。

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