一麥克風陣列迴音消除器及其ASIC設計

Abstract

在這篇論文中，我們提出一種新的迴音章消除器架構。這種迴音消除器使用麥克風陣列來擷取語音信號。由於麥克陣列的使用，我們可以用一個較短的適應性有限脈衝響應濾波器來模擬聲音通道。我們接著詳細說明所提出迴音消除器之動作方式。此外，我們提出一個新的方法來偵測雙邊通話的情況。這是藉由監測適應性濾波器加權係數向量的功率來達成。這個方法對於於雙邊通話的發生非常敏感，並且不會將房間響應的變化誤認為是雙邊通話。最後，我們從事所提出迴音消除器之ASIC設計。由於使用管線式以及硬體分享的技巧，我們的設計擁有很高的工作效率以及小的晶片面積。

In this thesis, a new structure for acoustic echo cancellation is presented. This echo canceller uses a microphone array to acquire speech signals. Due to the use of the microphone array, we can use a shorter adaptive FIR filter to identify the acoustic channel. We then describe the operations of the prooposed echo canceller in detail. Besides, a new approach to the detection of double - talk is proposed This is achieved by monitoring the power of the adaptive filter weight vector. Our method is very sensitive to the occurrence of double - talk and it can distinguish the room impulse response double - talk.Finally, we consider the ASIC design of the proposed echo canceller. Using the techniques of pipelining and hardware sharing, we are able to design the ASIC with a high working efficiency as well as a small chip area.