介质扰动对声波的调制效应-参量接收阵及其他

Modulation of sound by medium disturbance-parametric acoustic receiving array and others

文章从Lighthill方程出发,对介质扰动产生声传播非线性效应的国内、外研究情况进行了综述性介绍,重点介绍声波在被声场中同时存在的另一声波所扰动的介质中传播而产生的所谓“声散射声”现象,特别是由此而衍生的参量接收阵的理论、试验以及应用情况。绝大多数关于参量接收阵的理论和实验研究,都是着眼于其在小的径向(垂直于声传播方向)孔径条件下实现低频窄波束接收的特性,但这篇文章主要关注利用参量接收阵实现低频高增益接收的理论和试验研究;除重点介绍了国内、外的试验情况外,还特别关注将参量接收阵进行工程应用时面临的关键技术难点以及可能的解决思路。此外,文章还针对另一种介质扰动对声传播的调制效应,即“流散射声”,以及国外与此有关的工程应用、特别是苏联进行的号称超远程探潜应用进行了介绍和分析。

When the non-uniformity caused by medium disturbance must be considered,the wave equation is nonlinear.A general introduction to the effects of medium disturbance on wave propagation based on Lighthill wave equation is given in this paper.The emphases are on the phenomenon of‘scattering of sound by sound’,which is the problem about a sound wave in propagation modulated by the medium disturbance caused by another coexist sound wave,and especially on the theoretical and experimental researches of parametric acoustic receiving array,which is based on the concept derived from‘scattering of sound by sound’.Historically,most of the researches on parametric acoustic receiving array are about its characteristic of narrow beam-width,but the emphasis in this paper is about using parametric acoustic receiving array to achieve extremely high array gain for the detection of low frequency signals.The experiments of our own and others are introduced,and the key technical difficulties applying parametric receiving array in practical projects and the possible solution methods are analyzed.In addition,the effect of a sound wave in propagation modulated by ultra-low frequency wave flow and its applications in foreign countries are also introduced,especially about the experiment conducted by a Soviet-Union team,in which this effect was used for the so-called super-long-distance submarine detection.