超声调制的声频定向传输效率分析  

The Efficiency Analysis of Ultrasound-Modulated Audio Directional Transmission

作　　者：杜鹏[1] 汤惠[1] 曹光亮[1] 

机构地区：[1]电子科技大学电子科学技术研究院,四川成都611731

出　　处：《压电与声光》2015年第5期907-911,共5页Piezoelectrics & Acoustooptics

摘　　要：将音频信号调制到超声载波上发射出去,在空气的非线性作用下会发生自解调,可产生具有指向性的声音信号。在声频定向传输应用中,最大的问题是如何提高其转换效率。该文通过理论推导与计算,分析了影响超声调制的声频定向传输转换效率的相关参数。通过该文的分析计算可得,在外界环境不变的情况下,定向声频的声强及转换效率与发射超声波载波频率、发射超声波频率差、发射超声波源声强及发射声源面积等参数有关,因此,在设计声频定向传输系统时要综合考虑这些参数的影响。Modulated onto the ultrasonic carrier and transmitted,the audio signal will generate the self-modulation with the help of the air′s nonlinear effects and the good directivity can be obtained.In the applications of directional audio transmission,the biggest problem is how to improve the conversion efficiency.In this paper,we analyzed the parameters related to the efficiency of ultrasound-modulated audio directional transmission by a detailed theoretical derivation and calculation.Through the analysis and calculation,we know that with the external environment remaining unchanged,the intensity and efficiency of directional audio sound can be influenced greatly by the change of the carrier frequency and frequency difference of the emitted ultrasonic sound,the change of the intensity of emitted ultrasonic sound as well as the change of the emission source area.So in the design of audio directional transmission system we should take the impact of these parameters into consideration.

关 键 词：声散射理论 超声调制 声频定向 差频 效率 

分 类 号：TN912[电子电信—通信与信息系统]