针对不断增强的局部声重放需求，本项目围绕非线性多波束的局部声重放开展研究。项目以对声散射声机理、失真产生机理和阵列设计理论的深入研究为基础，通过理论、实验研究相结合的方式，重点探索并解决：1、基于非线性多波束的多频局部声重放；2、局部声重放的预处理方法研究；3、换能器阵列的优化设计研究，通过滤波器设计和优化处理，实现高效率，高质量的多频局部声重放的目标，从而保护隐私、避免干扰其他用户的目的。.本项目首次考虑了基于非线性多波束条件下的多频局部声重放，提出的信号处理算法具有高效率、高质量的优点，可有效实现在指定区域内的语音或音乐播放。本项目的开展将填补这些方面的空白，为非线性多波束应用于局部声重放中解决相应的技术障碍，推动局部声重放研究向实用化等更深层次发展。

Local sound reproduction system can simultaneously create two different kinds of zones- the bright zone, a target region where a desired sound field is reproduced, and the dark zone, a region where the sound pressure level needs to be attenuated. The system can be applied in the situation where multiple independent sound regions should be generated such as in automotive environment, or where the focusing sound should be reproduced such as in exhibition area. In recent years, the development of this system has been a hot topic in the research area of the sound field control. To the increasing needs in the local sound reproduction, the method using the nonlinear interactions among multiple beams will be investigated in this project..The mechanism of scattering sound by sound, its distortion, and the theory of the array design will be studied comprehensively. By combining the theoretical and experimental study, the problem of how to reproduce multiple tones, how to reduce the distortions and how to optimize the transducer array will be emphatically considered and analyzed. The final goal of this project is to establish a local sound including multiple tones with higher efficiency and lower distortion..Compared to the previous research, the novel local sound reproduction proposed by this project is much effective for generating multiple tones in the specified region with lower distortion. The work of this project is helpful for design and application of the local sound reproduction using the nonlinear interactions among multiple beams.