Comparison of CLEAN-SC for 2D and 3D scanning surfaces

We present experimental data comparing the accuracy obtained for 2D and 3D scanning surfaces using CLEAN-SC deconvolution of beamformed acoustic maps. A spherical array is used to obtain recordings from a dense point cloud of sound source locations. Beamforming and CLEAN-SC acoustic maps are generated using traditional 2D scanning surfaces and 3D scanning surfaces corresponding to the surface geometry of an object being acoustically imaged. Results for the 3D method show improved accuracy of measured positions and magnitudes of sound sources under a range of circumstances. The most benefit, in regard to position error, is for frequencies above 5kHz and sound sources located less than a metre from the array. In these circumstances, the three-dimensionality is more dominant.