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Published on: August 21, 2018
Wave field synthesis of a virtual source located in proximity to a loudspeaker array
Jung-Min Lee1, Jung-Woo Choi, Yang-Hann Kim
1Center for Noise and Vibration Control, Department of Mechanical Engineering, Korea Advanced Institute of Science and Technology, 291 Daehak-ro, Yuseong-gu, Daejeon 305-701, Korea. jungminlee@kaist.ac.kr
The Journal of the Acoustical Society of America
|August 24, 2013
Summary
This study introduces a new method for wave field synthesis, reducing virtual source reproduction errors near loudspeaker arrays. The technique improves accuracy for generating sound fields by combining near-field and far-field approaches.
Area of Science:
- Acoustics
- Signal Processing
- Computational Electromagnetics
Background:
- Wave field synthesis (WFS) typically uses far-field approximations for virtual sources.
- Placing virtual sources near loudspeaker arrays introduces significant reproduction errors with standard WFS.
Purpose of the Study:
- To develop a method for generating virtual sources close to continuous line loudspeaker arrays.
- To minimize reproduction errors in near-field wave field synthesis.
Main Methods:
- Derived a driving function by reducing a surface integral (Rayleigh integral) to a line integral using near-field assumptions.
- Combined the near-field solution with the far-field WFS formula using a weighting function.
- Introduced a weighting function to balance near- and far-field contributions.
Main Results:
- The proposed method successfully generates virtual sources close to and behind loudspeaker arrays.
- Simulations demonstrate a reduction in reproduction error to below -18 dB.
- The method is effective regardless of the virtual source's position relative to the array.
Conclusions:
- The novel approach effectively overcomes the limitations of far-field approximations in WFS.
- Accurate virtual source generation is achievable even in close proximity to loudspeaker arrays.
- This method enhances the flexibility and precision of wave field synthesis applications.
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