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A single sensor based active reflection control system using FxLMS algorithm

FxLMS를 이용한 단일 센서기반 능동 반향음 제어 시스템

  • 김재필 (연세대학교 멀티미디어 신호처리 연구실) ;
  • 지유나 (연세대학교 멀티미디어 신호처리 연구실) ;
  • 박영철 (연세대학교 멀티미디어 신호처리 연구실) ;
  • 서영수 (국방과학연구소)
  • Received : 2016.11.14
  • Accepted : 2017.01.25
  • Published : 2017.01.31

Abstract

This paper presents an active acoustic-reflection control algorithm based on a single sensor. The proposed algorithm operates in a system comprising a single sensor located nearby the reflective surface and a control transducer mounted on the reflective surface. First, the incident and reflected acoustic signals are separated from the sensor signal, and a control signal is generated using the separated signals. For the signal separation, the proposed algorithm requires the response of the reflection path which is estimated from the acoustic response between an external sound source and the sensor. Finally, the control filter is adjusted using the FxLMS (Filtered-x Least Mean Square) algorithm. To verify the effectiveness of the proposed algorithm, it was implemented in real time using a DSP (Digital Signal Processing) board, and the experimental results obtained in one-dimensional air-acoustic environment show that the reflections of the 1 kHz burst can be reduced by 11.6 dB.

본 논문에서는 FxLMS(Filtered-x Least Mean Square) 알고리즘을 이용한 단일 센서 기반의 능동 반향음 제어 알고리즘을 제안한다. 제안 알고리즘은 먼저 단일 센서 입력 신호로부터 입사음과 반향음을 분리하고, 분리된 신호들을 사용하여 반향음과 반대 위상을 갖는 제어 신호를 생성한다. 제어 신호는 센서 위치에서 반향음과 중첩되어 반향음의 음압을 감소시킨다. 적절한 신호 분리를 위해 반향 음향 경로와 제어 음향 경로가 필요하며 이는 swept sine 신호를 이용해 측정한 음향 응답으로부터 사전에 구할 수 있다. 효용성을 검증하기 위해 DSP(Digital Signal Processing) 보드를 사용하여 제안된 알고리즘을 실시간으로 구현하였으며, 공기 중 음향 덕트 환경에서 1 kHz 버스트 신호에 대해 반향음이 11.6 dB 감소함을 확인 하였다.

Keywords

References

  1. S. M. Kuo and D. R. Morgan, "Active noise control: a tutorial review," Proc. of the IEEE, 87, 943-973 (1999).
  2. B. Widrow, J. R. Glover, J. M. McCool, J. Kaunitz, C. S. Williams, R. H. Hearn, J. R. Zeidler, J. E. Dong, and R. C. Goodlin, "Adaptive noise cancelling: Principles and applications," Proc. of the IEEE, 63, 1692-1716 (1975)
  3. J. C. Burgess, "Active adaptive sound control in a duct: A computer simulation," J. Acoust. Soc. Am. 70, 715-726 (1981). https://doi.org/10.1121/1.386908
  4. P. R. Enderle and G. R. Batta, "Stability of active noise control systems in ducts," in Proc. Noise-Con, 1, 167-172 (1990).
  5. D. Guicking and K. Karcher, "Active impedance control for one-dimensional sound," J. Vib. Acoust. 106, 393-936 (1984). https://doi.org/10.1115/1.3269207
  6. M. Furstoss, D. Thenail, and M. Galland, "Surface impedance control for sound absorption: Direct and Hybrid Passive / Active Strategies," J. Sound. Vib. 203, 219-236 (1997). https://doi.org/10.1006/jsvi.1996.0905
  7. H. Zhu, R. Rajamani, and K. A. Stelson, "Active control of acoustic reflection, absorption, and transmission using thin panel speakers," J. Acoust. Soc. Am. 113, 852-870 (2003). https://doi.org/10.1121/1.1534834
  8. T. R. Howarth, V. K. Varadan, X. Bao, and V. V. Varadan, "Piezocomposite coating for active underwater sound reduction," J. Acoust. Soc. Am. 91, 823-831 (1992). https://doi.org/10.1121/1.402542
  9. C. Jung. "Active noise control techniques" (in Korean), J. Acoust. Soc. Kr. 11, 70-75 (1992).
  10. A. Farina, "Simultaneous measurement of impulse response and distortion with a swept-sine technique," AES 108th Convention, paper no.1-23 (2000).
  11. J. Kim, Y. Ji, and Y. Park, "Improved separation method of reflective path that appliable in single sensor based system," 2016 LOTC, 81-82 (2016).
  12. Marshall, "The production of acoustic impulse in the air," Meas. sci. Tecnol. 1, 413-418 (1990). https://doi.org/10.1088/0957-0233/1/5/007