臺灣博碩士論文加值系統

本文研究重點主要在解決ANC(Active Noise Control)系統之中，在消除噪音時，所產生的「聲音回饋」(Acoustic Feedback)問題，其架構是採用M.T. Akhtar所發表的架構，並修改其自適應性演算法，使原本FXLMS(Filter-X LMS)演算法的Step size能調整至最佳數值，我們將此演算法稱為MVS FXLMS(Modified Variable Step-size FXLMS)使系統收斂速度得到進一步的改善，在濾波器階數較低的情況下，還能保有一定程度的改善效果，使得在硬體實現時能做為成本降低的參考。最後，我們以輸入實際噪音來做測試，實驗結果證明此架構能實際運用於真實噪音，並且證明本文MVS FXLMS演算法在此架構也能實際運用於真實噪音之中。

This thesis is focused on the investigation of the acoustic feedback problem that is aroused when an active noise control (ANC) system is trying to eliminate noise. The Filter-X LMS (FXLMS) structure proposed by M.T. Akhtar is modified in such a way that the step size can be adjusted to an optimal value. The improved algorithm, which is named the modified variable step-size FXLMS (MVS FXLMS), has been demonstrated to achieve faster convergence than FXLMS. Moreover, we have found that, even under lower levels of filter design, MVS FXLMS still exhibits some improvement. This feature helps greatly on reducing its hardware cost. Finally, we use a real noise sources to test the feasibility of the system. Simulation results show that the proposed MVS FXLMS algorithm works satisfactorily well.

中文摘要---------------------------------------------------------------------------------------i
英文摘要---------------------------------------------------------------------------------------ii
誌謝---------------------------------------------------------------------------------------------iii
目錄---------------------------------------------------------------------------------------------iv
表目錄------------------------------------------------------------------------------------------v
圖目錄------------------------------------------------------------------------------------------vi
第一章 緒論 ---------------------------------------------------------------------------------1
1.1 前言 ----------------------------------------------------------------------------1
1.2 簡單噪音相關參數解釋 ----------------------------------------------------2
1.3 噪音型態 ----------------------------------------------------------------------3
1.4 噪音來源 ----------------------------------------------------------------------4
1.5 噪音對人體的影響 ----------------------------------------------------------4
1.6 章節提要 ----------------------------------------------------------------------5
第二章 主動式噪音控制原理及架構 ---------------------------------------------------6
2.1 文獻回顧 ----------------------------------------------------------------------6
2.2 主動式噪音控制架構 -------------------------------------------------------7
2.2.1 回授控制架構 (feedback control structure) -----------------------7
2.2.2 前饋控制架構 (feedforward control structure) -------------------8
2.2.3 複合架構 (hybrid control structure) --------------------------------9
2.3 控制器 -------------------------------------------------------------------------9
2.4 聲場回饋 (Acoustic Feedback) --------------------------------------------14
第三章 論文相關研究 ---------------------------------------------------------------------16
3.1 適應性LMS演算法 --------------------------------------------------------16
3.2 適應性FXLMS演算法 ----------------------------------------------------21
3.3 Modified VS LMS演算法 ------------------------------------------------24
3.4 本文架構 ----------------------------------------------------------------------27
第四章 模擬分析 ---------------------------------------------------------------------------31
4.1 單頻噪音 ----------------------------------------------------------------------32
4.2 複頻噪音 ----------------------------------------------------------------------43
4.3 寬頻噪音 ----------------------------------------------------------------------47
4.4 真實噪音模擬 ----------------------------------------------------------------51
4.5 結論 ----------------------------------------------------------------------------60
第五章 結論與未來研究方向 ------------------------------------------------------------61
參考文獻 --------------------------------------------------------------------------------------62
簡歷 --------------------------------------------------------------------------------------------64

[1] P.A. Nelson and S.J. Elliot, 1992 ,”Active Control of Sound.”,Academic,New
York.
[2] P.Lueg ,1936, “Process of Silencing Sound Oscillator”,U.S. Patent No.2043416.
[3] H.F. Olson ,and, E.G. May, 1953 , “Electronic sound absorbers”,J.Acoust. Soc. Am.,25, 6 , pp.1130-1136.
[4] M.A. Swinbanks,1973, “The active control of sound propagation in long ducts”,J.Sound and Vibration,Vol. 27 ,pp. 441-436.
[5] Kido, K. ,1975 , “Reduction of Noise by Use of Additional Sound,” Proceedings of InterNoise , Sendai, pp.649-650.
[6] Burgess, J. C. , 1981, ”Active Adaptive Sound Control in a Duct: a Computer Simulation,” J. Acoust. Soc. Am., Vol.70, pp.715-726.
[7] Eriksson L. J. ,1991, “Development of the Filtered-U Algorithm for Active Noise Control,” J. Acou. Soc. Am. Jan , Vol89, No.1, pp.257-265.
[8] D.P. Das and G . Panda, 2004 , “Active mitigation of nonlinear noise processes using a novel filtered-s LMS algorithm,” IEEE Trans. Speech and Audio Processing , Vol.12, No.3.,May.
[9] 廖素勤，2002， “新生兒保溫箱主動式噪音控制之研究”，國立成功大學，
碩士論文。
[10]沈建宏，2002，“引擎排氣噪音之主動式消音器研究”，華梵大學，碩士論
文。
[11]盧士一，2006，“風管氣動噪音模擬與主動控制研究”，行政院勞工委員會勞工安全衛生研究所。
[12]林永常，2001，“火箭發射噪音之主動控制研究”，國立中央大學，碩士論
文。
[13] Kuo, S.M. Mitra, S. Woon-Seng Gan, 2006 ,“Active noise control system for
headphone applications”,Control Systems Technology. IEEE, March.
[14] 白明憲，1999， “聲學理論與應用-主動式噪音控制”，全華科技圖
書股份有限公司，台北市
[15] L.J Eriksson and M.C. Allie, 1989, “Use of random noise for on-line transducer
modeling in an adaptive active attenuation system” , J. Acoust. Soc.Amer., Vol.85, No.2, pp.797-802.
[16] Sen M. Kuo and Dipa Vijayan , 1997, “A Secondary Path Modeling Technique
for Active Noise Control Systems”,Speech and audio processing , IEEE
VOL. 5, NO. 4.,July.
[17] M . Zhang, H . Lan, and W. Ser, 2000, “An improved secondary path modeling
method for active noise control systems”, IEEE Signal Processing Letters,vol.
7,pp.73-75.
[18] M . Zhang, H . Lan, and W. Ser, 2002 ,“An active noise control systems using
online secondary path modeling with reduced auxiliary noise”,IEEE Signal Processing Letters, vol. 9,pp.16-18.,Jan.
[19] C. Bao, P. Sas, and H. Van Brussel, 1993, “Comparison of two online
identification algorithms for active noise control”, in Proc. Recent Advances in
Active Control of Sound Vibration,pp.38-51.
[20] Li Yan and Wang Xinan , 2007, “A Modified VS LMS Algorithm”,
12-14,ICACT .,Fed.
[21] K.Mayyas and T. Aboulnasr, 1995 ,“A Robust Variable Step Size LMS-Type
Algorithm: Analysis and Simulations”, IEEE.
[22] V. John Mathews and ZHenhua Xie, 1993 ,“A Stochastic Gradient Adaptive
Filter with Gradient Adaptive Step Size”, IEEE Tranaction on Signal Processing.
Vol. 41.No.6.June.
[23] Raymond H. Kwong and Edward W. Johnston, 1992, “A Variable Step Size LMS
Algorithm”, IEEE Tranaction on Signal Processing. Vol. 40. No. 7.July.
[24] Muhammad Tahir Akhtar,Masahide Abe,and Masayuki Kawamata, 2007, “On
Active Noise Control Systems with Online Acoustic Feedback Path
Modeling”,IEEE Transactions on Audio,Speech,and Language Processing, Vol.
15,No.2, Feb.
[25] S. M. Kuo, ,2002 ,“Active Noise Control Systems and Method for On-Line
Feedback path Modeling”, U.S. Patent 6,418,227, Jul.9.
[26] L. Tan and J. Jiang, 2001 ,“Adaptive Volterra Filters for Active Control of
Nonlinear Noise Processes” IEEE Trans. Signal Processing, vol. 49, pp.
1667–1676, Aug.