多周期伪随机序列扩散体近场接收点的优化选择  

Optimization of Distance from Receiver to Multi-period Pseudorandom Diffusers in Near Field

作　　者：杨健斌[1] 沈勇[1] 

机构地区：[1]南京大学声学研究所近代声学重点实验室,江苏南京210093

出　　处：《电声技术》2006年第4期10-13,共4页Audio Engineering

基　　金：国家自然科学基金(10474046).

摘　　要：在远场条件下,伪随机序列扩散体具有良好的扩散特性。多周期的伪随机序列扩散体越来越多地应用在各种小型房间里,接收点到多周期伪随机序列扩散体的距离并不满足远场条件。根据基尔霍夫衍射理论,研究了扩散频率范围内接收点在近场时多周期伪随机序列扩散体的极性响应,并与平板进行了比较和分析,总结出表征扩散性能变化的过渡距离。实际使用时要适当选择接收点距离,使既能获得良好的扩散效果,又能保证一定的声压级。Under the condition of far field,pseudorandom diffusers have good diffusion characteristics. Multi-period pseudorandom diffusers are more and more used in small rooms, where the distance from receiver to diffusers is limited to be too small to satisfy the far field condition. In this paper,Kirchhoff＇s theory is used to study the polar response of diffusers when receiver is in near field within diffusion bandwidth. Compared with the response of panels,a concept of transition distance is introduced to show the variation of diffusion characteristic. In appllcation,the distance from receiver to diffusers should be carefully determined to gain good diffusion and enough sound level.

关 键 词：伪随机序列扩散体 极性响应 过渡距离 

分 类 号：O422[理学—声学]