广义逆波束形成是一种基于传声器阵列的高效声源识别技术。然而面对复杂声源,受限于较差的旁瓣抑制能力以及较低的动态显示范围,难以实现高精度的声源识别定位。为提高广义逆波束形成声源识别的动力学水平,结合函数波束形成,提出一种函数广义逆波束形成方法。从广义逆波束形成与矩阵函数分析出发,全面阐述函数广义逆波束形成基本理论,详细分析不同声源类型和测量误差等因素对其声源成像性能的影响,得到阶次数的最佳取值应用范围。通过数值仿真模型和试验算例进行声源成像仿真,结果表明,函数广义逆波束形成,在保证准确识别声源强度与声源方位的基础上,通过增加阶次数能成倍提高波束旁瓣抑制能力,从而保证其拥有更高的空间分辨率能更精准定位声源。
Generalized inverse beamforming is a kind of highly effective and widely used sound source identification technology based on the microphone array. However, the performance of traditional generalized inverse beamforming is still limited by its poor side-lobe suppression capability and low dynamic range when identifying complex sound sources. It is difficult to achieve high accuracy of sound source identification. To improve the dynamic level of the generalized inverse beamforming, a new identification method based on functional beamforming is presented, which is named functional generalized inverse beamforming. The basic theory of functional generalized inverse beamforming is introduced by discussing the conventional generalized inverse beamforming and matrix functions. The influences of the source type and measurement error on the performance of sound source maps have been investigated. The range of typical order is determined by the analysis results. The results of numerical simulations and experiments show that the proposed algorithm can ensure the accurate identification of sound source intensity and location, and it also remarkably suppresses beamforming sidelobes by increasing the value of order. Therefore, the proposed algorithm can lead to higher spatial resolution and more accurate sound source localization compared with the conventional generalized inverse beamforming.
[1] 李兵, 杨殿阁, 郑四发, 等. 基于遗传算法的动态优化波叠加噪声源识别方法[J]. 机械工程学报, 2010, 46(12)：99-105.
LI Bing, YANG Diange, ZHENG Sifa, et al. Sound source identification method with dynamic optimal wave superposition algorithm based on genetic algorithm[J]. Journal of Mechanical Engineering, 2010, 46(12)： 99-105.
[2] 李兵, 杨殿阁, 邵林, 等. 基于波束形成和双目视觉的行驶汽车噪声源识别[J]. 汽车工程, 2008, 30(10)：889-892.
LI Bing, YANG Diange, SHAO Lin, et al. Noise sources measurement and identification for moving automobiles [J]. Automotive Engineering, 2008, 30(10)：889-892.
[3] 郝鹏, 郑四发, 连小珉. 运动噪声源的时域传递路径模型及贡献率分析[J]. 机械工程学报, 2012, 48(8)：104-109.
HAO Peng, ZHENG Sifa, LIAN Xiaomin. Time-domain transfer path modal and contribution analysis of moving noise sources[J]. Journal of Mechanical Engineering, 2012, 48(8)：104-109.
[4] LEE C, LEE J H. Robust adaptive array beamforming under steering vector[J]. IEEE Transactions on Antennas and Propagation, 1997, 45(1)：168-175.
[5] HALD J. Combined NAH and beamforming using the same microphone array[J]. Sound and Vibration, 2004, 38(12)：18-25.
[6] BROOKS T F, HUMPHREYS W M. A deconvolution approach for the mapping of acoustic sources (DAMAS) determined from phased microphone arrays[J]. Journal of Sound and Vibration, 2006, 294(4-5)：856-879.
[7] FLEURY V, BULTÉ J. Extension of deconvolution algorithms for the mapping of moving acoustic sources[J]. J. Acoust. Soc. Am, 2011, 129(3)：1417-1428.
[8] GAUTHIER P A, CAMIER C, PASCO Y, et al. Beamforming regularization matrix and inverse problems applied to sound field measurement and extrapolation using microphone array[J]. Journal of Sound and Vibration, 2011, 330(24)：5852-5877.
[9] SUZUKI T. L1 generalized inverse beam-forming algorithm resolving coherent /incoherent, distributed and multipole sources[J]. Journal of Sound and Vibration, 2011, 330(24)：5835-5851.
[10] DOUGHERTY R P. Functional beamforming for aeroacoustic source distributions[C]// The 20th AIAA/CEAS Aeroacoustics Conference, Atlanta, GA, United States, June 16-20, 2014：1-18.
[11] CALVETTI D, MORIGI S, REICHEL L, et al. Tikhonov regularization and the L-curve for large discrete ill-posed problems[J]. Journal of Computational and Applied Mathematics, 2000, 123(1-2)：423-446.
[12] FLAVIO P, PAULO Z, GUNTHER S, et al. Acoustic source identification using a generalized weighted inverse beamforming technique[J]. Mechanical Systems and Signal Processing, 2012, 32(10)：349-358.
[13] WITKOWSKI A. A new proof of the monotonicity of power means [J]. Journal of Inequalities in Pure and Applied Mathematics, 2004, 5(1)：73-74.
