Liu Zhenghong, Zhou Haocheng, Song Xiyu, Wang Mei, Weng Liuqing
School of Information and Communication, Guilin University of Electronic Technology, Guilin 541004, China.
Ministry of Education Key Laboratory of Cognitive Radio and Information Processing, Guilin 541004, China.
Sensors (Basel). 2023 Oct 12;23(20):8403. doi: 10.3390/s23208403.
Sidelobe suppression is a major challenge in wideband beamforming for acoustic research, especially in high noise and reverberation environments. In this paper, we propose a multi-objective NSGA-II wideband beamforming method based on a spherical harmonic domain for spherical microphone arrays topology. The method takes white noise gain, directional index and maximum sidelobe level as the optimization objectives of broadband beamforming, adopts the NSGA-II optimization strategy with constraints to estimate the Pareto optimal solution, and provides three-dimensional broadband beamforming capability. Our method provides superior sidelobe suppression across different spherical harmonic orders compared to commonly used multi-constrained single-objective optimal beamforming methods. We also validate the effectiveness of our proposed method in a conference room setting. The proposed method achieves a white noise gain of 8.28 dB and a maximum sidelobe level of -23.42 dB at low frequency, while at high frequency it yields comparable directivity index results to both DolphChebyshev and SOCP methods, but outperforms them in terms of white noise gain and maximum sidelobe level, measuring 16.14 dB and -25.18 dB, respectively.
旁瓣抑制是声学研究中宽带波束形成的一项重大挑战，尤其是在高噪声和混响环境中。在本文中，我们针对球形麦克风阵列拓扑结构提出了一种基于球谐域的多目标NSGA-II宽带波束形成方法。该方法将白噪声增益、指向性指数和最大旁瓣电平作为宽带波束形成的优化目标，采用带约束的NSGA-II优化策略来估计帕累托最优解，并提供三维宽带波束形成能力。与常用的多约束单目标最优波束形成方法相比，我们的方法在不同球谐阶数下都能提供卓越的旁瓣抑制效果。我们还在会议室环境中验证了所提方法的有效性。所提方法在低频时实现了8.28 dB的白噪声增益和-23.42 dB的最大旁瓣电平，而在高频时，其指向性指数结果与DolphChebyshev方法和二阶锥规划（SOCP）方法相当，但在白噪声增益和最大旁瓣电平方面表现更优，分别为16.14 dB和-25.18 dB。
