Yon Sylvain, Tanter Mickaël, Fink Mathias
Laboratoire Ondes et Acoustique, Université Paris VII/ESPCI, CNRS UMR 7587, 10 rue Vauquelin, 75231 Paris Cedex 05, France.
J Acoust Soc Am. 2003 Dec;114(6 Pt 1):3044-52. doi: 10.1121/1.1628247.
The potential of time reversal processing for room acoustics has been extensively investigated in the companion of this paper [J. Acoust. Soc. Am. 113(3), 1533-1543 (2003)]. In particular, a simple implementation of a loudspeaker time reversal antenna able to take advantage of the multiple reflections in reverberating rooms demonstrates its potential for audible range acoustics while improving focusing both in space and time. However, loss of information (e.g., sound absorption in walls or nonequalized bandwidths of the loudspeakers) during a time reversal experiment degrades the quality of time reversal focusing. In this paper, a more sophisticated technique called spatio-temporal inverse filtering is investigated that achieves time and space deconvolution of the propagation operator between the loudspeakers antenna and a set of microphones embedded inside the insonified volume. Theoretical and experimental comparisons between time reversal and inverse filter focusing are presented. Finally, advantages and limitations of both focusing approaches are highlighted.
在本文的参考文献[《美国声学学会杂志》113(3)，1533 - 1543(2003)]中，已经对时间反转处理在室内声学中的潜力进行了广泛研究。特别地，一种能够利用混响室内多次反射的扬声器时间反转天线的简单实现方式，展示了其在可听声范围声学中的潜力，同时在空间和时间上都改善了聚焦效果。然而，在时间反转实验期间信息的丢失（例如，墙壁中的声音吸收或扬声器的未均衡带宽）会降低时间反转聚焦的质量。在本文中，研究了一种更复杂的技术，称为时空逆滤波，它实现了扬声器天线与嵌入被声照射体积内的一组麦克风之间传播算子的时间和空间反卷积。给出了时间反转聚焦和逆滤波器聚焦之间的理论和实验比较。最后，强调了两种聚焦方法的优点和局限性。
