Sidelobe suppression in loudspeaker line array via sparse optimization

Yuxin  Liu; Hui  Ren; Zhen  Li; Qian Zhou

doi:10.59400/sv3785

Sidelobe suppression in loudspeaker line array via sparse optimization

Yuxin Liu
School of Information and Communication Engineering, Communication University of China, Beijing 100024, China
Hui Ren
School of Information and Communication Engineering, Communication University of China, Beijing 100024, China
Zhen Li
School of Information and Communication Engineering, Communication University of China, Beijing 100024, China
Qian Zhou
School of Information and Communication Engineering, Communication University of China, Beijing 100024, China

Article ID: 3785

DOI: https://doi.org/10.59400/sv3785

Keywords: loudspeaker line array; sparse array; sidelobe suppression; optimization algorithm; beam steering

Abstract

Loudspeaker line arrays, widely deployed in venues such as theaters, stadiums, cinemas, and conference halls, are used to achieve uniform sound field coverage and directional control. Due to the spatial sampling effect of the loudspeaker-line-array discrete structure on an ideal continuous line source, periodic sidelobes inevitably appear in the sound radiation directivity pattern, whose pressure level increases with frequency. To mitigate this problem, a sidelobe suppression approach based on sparse array optimization is proposed. To reduce peak side lobe sound pressure levels, particle swarm optimization (PSO) and constrained genetic algorithms (GA) are employed to achieve random sparse optimization of array element positions and sparse optimization of structural symmetry in loudspeaker line array, respectively. Furthermore, due to the increased side lobe sound pressure level after beam steering, a beam steering algorithm combining sparse constraints with an improved Cosh criterion was proposed to achieve effective side lobe suppression following beam steering. This algorithm maintains the sidelobe suppression effect while achieving digital beam steering, allowing the main beam to be directed to a specific direction without requiring mechanical movement. The simulation results indicate that, by sparsifying loudspeaker units, the proposed method effectively suppresses the sidelobe sound pressure levels, with acceptable performance degradation in main-beam gain. In addition, flexible digital beam steering is archived with the sparsely optimized loudspeaker arrays in a low sidelobe level.

Published

2026-02-04

How to Cite

Liu, Y., Ren, H., Li, Z., & Zhou, Q. (2026). Sidelobe suppression in loudspeaker line array via sparse optimization. Sound & Vibration, 60(1). https://doi.org/10.59400/sv3785

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Issue

Vol. 60 No. 1 (2026)

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Article

This work is licensed under a Creative Commons Attribution 4.0 International License.

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