Binaural Range Finding from Synthetic Aperture Computation as the Head is Turned
Binaural Range Finding from Synthetic Aperture Computation as the Head is Turned
复制标题
当头部转动时通过合成孔径计算寻找双耳范围
作者：
D. Tamsett
Tamsett(Robotics 2017，6(1)，3)中描述的双耳测向的解决方案是在收听声音的同时转动头部时执行的合成孔径计算(SAC)。文中放松了该文中的一个远程近似，并将该方法推广到SAC，作为距离的函数来估计声源的距离。在听轴和声源方向之间的瞬时角度λ(波长)将声源定位在围绕听轴对称的球体的一个小纬度圆(波长圆)上。随着头部的转动，在连续的瞬时波长圆周上的数据被积分到虚拟试听场中，从该虚拟试听场可以推断到声源的方向。作为范围的函数而生成的多组波长圆产生最佳范围，在该最佳范围处，圆相交以在虚拟三维听力场中的点处最佳聚焦，从而提供范围的估计。用模拟实验数据证明了概念的正确性。该方法使双耳机器人不仅能够通过足够准确地测量天线处的到达时间/电平差来估计方向，而且还能够估计到声源的范围。
A solution to binaural direction finding described in Tamsett (Robotics 2017, 6(1), 3) is a synthetic aperture computation (SAC) performed as the head is turned while listening to a sound. A far-range approximation in that paper is relaxed in this one and the method extended for SAC as a function of range for estimating range to an acoustic source. An instantaneous angle λ (lambda) between the auditory axis and direction to an acoustic source locates the source on a small circle of colatitude (lambda circle) of a sphere symmetric about the auditory axis. As the head is turned, data over successive instantaneous lambda circles are integrated in a virtual field of audition from which the direction to an acoustic source can be inferred. Multiple sets of lambda circles generated as a function of range yield an optimal range at which the circles intersect to best focus at a point in a virtual three-dimensional field of audition, providing an estimate of range. A proof of concept is demonstrated using simulated experimental data. The method enables a binaural robot to estimate not only direction but also range to an acoustic source from sufficiently accurate measurements of arrival time/level differences at the antennae.