球谐域类正则化宽带超指向性波束形成算法  

Robust broadband regularized superdirective beamforming in the spherical harmonic domain

作　　者：厉剑[1,2] 柯雨璇 彭任华 郑成诗 李晓东[1] LI Jian;KE Yuxuan;PENG Renhua;ZHENG Chengshi;LI Xiaodong(Key Laboratory of Noise and Vibration Research,Institute of Acoustics,Chinese A cademy of Sciences Beijing,100190;University of Chinese Academy of Sciences Beijing,100049)

机构地区：[1]中国科学院声学研究所噪声与振动重点实验室,北京100190 [2]中国科学院大学,北京100049

出　　处：《声学学报》2020年第2期145-160,共16页Acta Acustica

基　　金：国家自然科学基金项目(61571435,61801468)资助。

摘　　要：提出一种球谐域类正则化宽带超指向性波束形成算法,通过结合超指向性波束形成器与延迟求和波束形成器控制阵列白噪声增益和指向性因数,推导类正则化宽带超指向性波束形器的球谐域表达式。在此基础上设计新的可控指向性因数波束形成器,可在不显著放大低频白噪声的前提下实现设定的波束宽度。采用32元球阵的仿真结果表明,对于语音测试场景,类正则化波束形成器的最高PESQ得分相比于传统的超指向性波束形成器与延迟求和波束形成器分别提高了约0.5和0.4,平均词错率分别减少了约9.5%和8.1%。主观测试实验也表明类正则化波束形成器在方向性噪声和扩散场噪声环境下都可以获得更好的主观听觉感受。利用实验数据对算法性能进行测试,实验结果同样验证了该方法在实际声学环境中的有效性。A robust broadband regularized superdirective beamformer which combines the superdirective beamformer and the delay-and-sum beamformer in the spherical harmonic domain is proposed.First,the analytic closed-form expression of the regularized superdirective beamformer is derived by controlling the white noise gain and the directivity factor.Then a new beamformer with the desired DF is designed so as to obtain an adequate WNG with realtive high DF for low frequencies.Simulation results with a 32-channel spherical array show that compared to the superdirective beamformer and the delay-and-sum beamformer,the proposed beamfomer can improve the highest PESQ score by 0.5 and0.4 and reduce the average WER by 9.5% and 8.1% respectively.In the directional noise and diffuse noise environments,the proposed beamfomer also shows better performnace in subjective listeing tests.The experimental results confirm the validity of the proposed method in real acoustic environments.

关 键 词：波束形成器 指向性指数 白噪声增益 波束宽度 波束形成算法 正则化 

分 类 号：TN911.7[电子电信—通信与信息系统]