Binaural Directivity Pattern Measurements of the KEMAR Head Model with Two Twin Hearing Aid Microphones

양이 각각 두 개의 보청기 마이크로폰을 장착한 KEMAR 머리 모델의 양이 방향성 측정

  • Jarng, Soon-Suck (Dept. of Information Communication Eng., Chosun University) ;
  • Kwon, You-Jung (Dept. of Information Communication Eng., Chosun University) ;
  • Lee, Je-Hyeong (Dept. of Information Communication Eng., Chosun University)
  • Published : 2006.03.31

Abstract

Two twin microphones may produce particular patterns of binaural directivity by time delays between the twin microphones. The boundary element method (BEM) was used for the simulation of the sound pressure field around the KEMAR head model in order to quantify the acoustic head effect. The sound pressure onto the microphone was calculated by the BEM to an incident sound pressure. Then a planar directivity pattern was formed by four sound pressure signals from four microphones. The optimal binaural directivity pattern may be achieved by adjusting time delays at each frequency while maintaining the forward beam pattern is relatively bigger than the backward beam pattern. The simulation results were verified by the experimental measurement.

Keywords

References

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