數位信號處理晶片應用於聲源訊號雜訊消除之研究

The Research of Digital Signal Processing Chip Set Applied on Acoustic Signal De-noising

滕有揚(You-Yang Teng)

指導教授 ： 杜筑奎

中原大學/工學院/資訊工程研究所/碩士(2004年)

https://doi.org/10.6840/cycu200400155

摘要

各種聲源訊號在傳播過程中，由於受到環境之影響，與各種噪音之滲入，在接收後必須作適確的訊號處理，才能將經過長距離傳送而能量衰減，且被環境干擾的訊息分辨出來。本研究對聲源訊號作雜訊消減之系統設計，以小波轉換作雜訊消減之處理。此方法可分為三個步驟：(1)聲源訊號作小波轉換(2)對小波訊號進行縮移(3)利用反小波轉換重建調整過的信號。而在第二步驟中，將使用不同臨界值選取法，並比較不同方法所得之辨識結果。

本系統平台建構於TI TMS320C6711 DSK，目的在利用其快速的數位信號處理速度，減少聲源訊號的訓練和辨識時間。

關鍵字

聲源訊號 ； 小波轉換 ； TMS320C6711 DSK ； 雜訊消除

並列摘要

In the process of transmitting various acoustic signals , because of being affected by the environment and all kinds of noises that permeate through the propagation channel, it is necessary to have an appropriate signal processing procedure to identify the signals which energy is already decreased by long distance transmission and environment interruption. This research is based in a wavelet-based method by choosing threshold value for de-noising. The procedure is divided into three stages: (1) Wavelet transform of the acoustic signals (2) Thresholding of wavelet signals (3) Inverse wavelet transform to reconstruct modified signals. The most important part is second stage, which uses different threshold-selecting rule to compare the performace for the recognition of the acoustic signals.

The developed system is based on TI TMS320C6711 DSK. Since it reveal high performace for digital signal processing,it can reduce the training and recognizing time for the acoustic signal recognization .

並列關鍵字

Acoustic signal ； de-noising ； wavetlet thansform ； TMS320C6711 DSK

參考文獻

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