Department of Electronic and Information Engineering, Hong Kong Polytechnic University, Hung Hom Kowloon KLN, Hong Kong.
J Acoust Soc Am. 2013 Apr;133(4):1987-95. doi: 10.1121/1.4792149.
An acoustic vector-sensor consists of three identical but orthogonally oriented acoustic particle-velocity sensors, plus a pressure sensor-all spatially collocated in a point-like geometry. At any point in space, this tri-axial acoustic vector-sensor can sample an acoustic wavefield as a 3 × 1 vector, instead of simply as a scalar of pressure. This vector, after proper self-normalization, would indicate the incident wave-field's propagation direction, and thus the incident emitter's azimuth-elevation direction-of-arrival. This "self-normalization" direction-of-arrival estimator is predicated on the spatial-collocation among the three particle-velocity sensors and the pressure-sensor. This collocation constriction is relaxed here by this presently proposed idea, to realize a spatially distributed acoustic vector-sensor, allowing its four component-sensors to be separately located. This proposed scheme not only retains the algorithmic advantages of the aforementioned "self-normalization" direction-of-arrival estimator, but also will significantly extend the spatial aperture to improve the direction-finding accuracy by orders of magnitude.
声学矢量传感器由三个相同但正交取向的声学质点速度传感器和一个压力传感器组成，所有传感器都位于一个点状的空间位置上。在空间中的任何一点，这个三轴声学矢量传感器可以对声场进行 3×1 向量采样，而不仅仅是对压力进行标量采样。这个向量经过适当的自归一化后，可以指示入射波场的传播方向，从而指示入射发射器的方位-俯仰到达方向。这种“自归一化”到达方向估计器基于三个质点速度传感器和压力传感器之间的空间共置。通过目前提出的这个想法，可以放宽这种空间共置的限制，实现空间分布式声学矢量传感器，允许其四个分量传感器分别位于不同位置。这个方案不仅保留了上述“自归一化”到达方向估计器的算法优势，而且还可以显著扩展空间孔径，提高测向精度，提高幅度可达几个数量级。
