Continuous scan beamforming with CLEAN-SC for mapping of highly varying amplitude acoustic sources with significantly restricted sensor budgets

Continuous scan beamforming (CSBF) is a novel approach that employs virtual sensors to improve array performance without increasing the physical number of sensors. Previous CSBF demonstrations (at the Spring 2019 ASA meeting in Louisville, KY) showed the capability to perform high resolution mapping of acoustic sources and identify almost an 18 dB difference in source level, which was not possible using conventional beamforming with an equal sensor budget. The current work investigated the capability of CSBF combined with CLEAN-SC for conducting source localization with significantly reduced sensor budgets (on the order of ten sensors), in which conventional beamforming is practically impossible to obtain appreciable results. Results of a four-speaker noise test showed that CSBF can perform accurate identification of the locations and levels of the sources with such restricted sensor counts, and can provide an accurate input to CLEAN-SC for further enhancement of the source map.