A time-domain nearfield beamformer with spherical harmonic decomposition

Fei Ma; Thushara D Abhayapala; Prasanga N Samarasinghe

doi:10.1121/10.0021068

A time-domain nearfield beamformer with spherical harmonic decomposition

J Acoust Soc Am. 2023 Sep 1;154(3):1850-1861. doi: 10.1121/10.0021068.

Authors

Fei Ma¹, Thushara D Abhayapala¹, Prasanga N Samarasinghe¹

Affiliation

¹ College of Engineering and Computer Science, The Australian National University, Canberra, Australian Capital Territory 0200, Australia.

PMID: 37747144
DOI: 10.1121/10.0021068

Abstract

This paper proposes a time-domain nearfield beamformer with spherical harmonic decomposition. The beamformer design is separated into two stages: sound field measurement and beamformer coefficient design. This makes it easier for the beamformer to be implemented by different array structures. The beamformer coefficients are further separated into several parts, making it easier to design a beamformer with different characteristics. The time-domain implementation minimizes the latency between the array input and the beamformer response, and the nearfield focusing improves the farfield noise suppression ability of the beamformer. The proposed beamformer could be useful for emerging acoustic applications such as virtual reality and drones, and for further development of more advanced real-time nearfield beamformers. Simulations and experiments examine the performance of the proposed beamformer.