基于时间反转的复杂声场拾声传声器阵列性能研究

Time reversal microphone array systems for targeting sound sources in complex sound fields

探讨时间反转技术在复杂声场传声器阵列拾声中应用的可行性及其机理,给出其一般规律和性能。研究表明:在自由空间中,其拾声性能与频率,阵列形状和半径有关,频率越高,半径越大,拾声效果越好。在普通房间中,在语音频段内,圆弧阵列在预定目标点处的阵列增益性能要比离预定目标点约25 cm远处的位置处大5 dB以上。在普通房间和混响室中的实验验证了上述结论。

A microphone array system based on the time reversal technique for targeting sound sources in complex sound fields is investigated in this paper.The feasibility and mechanism of the microphone array system are studied and the performance and basic rules are given.It is found that in free sound field,its performance is relevant to frequency,the shape and radius of the array.The higher frequency and the larger radius of the array,the better the array performance will be.In a common room,the array gain of a circle array at a predefined focus point can be more than 5 dB larger than that at other places about 25 cm far from the predefined focus point in the speech frequency range.The experiment in a common room and a reverberant room verified the above conclusions.