Wang Xianghui, Benesty Jacob, Cohen Israel, Chen Jingdong
Center of Intelligent Acoustics and Immersive Communications and School of Marine Science and Technology, Northwestern Polytechnical University, 127 Youyi West Road, Xi'an 710072, China.
Institut National de la Recherche Scientifique, Centre Énergie Matériaux Télécommunications, University of Quebec, 800 de la Gauchetiere Ouest, Montreal, Quebec H5A 1K6, Canada.
J Acoust Soc Am. 2018 Dec;144(6):3450. doi: 10.1121/1.5082548.
Microphone arrays are typically used in room acoustic environments to acquire high fidelity audio and speech signals while suppressing noise, interference, and reverberation. In many application scenarios, interference and reverberation may mainly come from a certain region, and it is therefore necessary to develop beamformers that can preserve signals of interest while minimizing the power of signals coming from the region where interference and reverberation dominate. For this purpose, this paper first reexamines the so-called front-to-back ratio and the classical supercardioid beamformer. To deal with the white noise amplification problem and the limited directivity factor associated with the supercardioid beamformer, a set of reduced-rank beamformers are deduced by using the well-known joint diagonalization technique, which can make compromises between the front-to-back ratio and the amount of white noise amplification or the directivity factor. Then, the definition of the front-to-back ratio is extended to a generalized version, from which another set of reduced-rank beamformers and their regularized versions are developed. Simulations are conducted to illustrate the properties and advantages of the proposed beamformers.
麦克风阵列通常用于室内声学环境中，以获取高保真音频和语音信号，同时抑制噪声、干扰和混响。在许多应用场景中，干扰和混响可能主要来自某个区域，因此有必要开发能够在最小化来自干扰和混响主导区域的信号功率的同时保留感兴趣信号的波束形成器。为此，本文首先重新审视了所谓的前后比和经典超心形波束形成器。为了解决与超心形波束形成器相关的白噪声放大问题和有限的方向性因子，利用著名的联合对角化技术推导出一组降秩波束形成器，该技术可以在前后比与白噪声放大量或方向性因子之间做出折衷。然后，将前后比的定义扩展到广义版本，由此开发出另一组降秩波束形成器及其正则化版本。通过仿真来说明所提出波束形成器的特性和优点。
