可听声

声波定向传播扬声器是一种新型的扬声器，它利用超声波与空气的非线性相互作用产生高指向性的自解调可听声，可以实现可听声波的定向传播。

Directional loudspeaker , being a new type of loudspeaker , can generate high directional audible sound , which depends on the self-demodulation of non-linear interaction between the ultrasound and air .

低层大气中可听声超额衰减的测量

The measured excess attenuation of audible sound in lower atmosphere

声频定向系统是一种新概念扬声器，能够将可听声投射到某一指定区域内。

Audio directional system is a new kind of loudspeaker , which can project the audible sounds onto a given region .

参量声源是一种根据声参量阵原理，利用声波在空气中的非线性传播效应以产生高指向性可听声的新型声源。

According to the parametric acoustic array theory , the parametric loudspeaker can generate highly directional audible sound using the nonlinear effects of air .

声频定向扬声器与传统扬声器相比有本质的不同，其主要是利用超声波信号在空气中的非线性作用产生可听声差频信号，其得到的差频信号具有良好的指向性。

The principal of audio directional speaker is fundamentally different from that of the traditional ones . The directional audible signal generated by audio directional loudspeaker is achieved by the nonlinear interaction of ultrasonic signal in the air .

摘要次声是不可听声，综合国内外的研究，介绍了次声对动物心血管系统、神经系统、听觉、视觉等的影响，及其在医疗器械中的应用，分析了次声的阈值问题。

This article summarizes the investigation on infrasound at home and abroad and introduces such issues about infrasound as the effects of infrasound on cardio-vascular system , nervous system , audition and vision , its application to medical device as well as its safe-threshold .

提出了一种利用空气中超声波非线性传播效应制作的、可产生高指向性可听声的新型声束扬声器。

A novel audio beam loudspeaker which based on nonlinear propagation effects of ultrasonic in the air to generate audible sound with high directivity is presented .