Particle velocity gradient based acoustic mode beamforming for linear vector sensor arrays

In this paper, a new method for processing signals measured using a linear array of sensors capable of measuring both the acoustic pressure and the particle motion is described. The method relies on extracting the acoustic modes of the propagating wavefield using the spatial gradients of the field variables. Numerical simulations reveal that the proposed broadband beamformer achieves a directivity factor comparable to conventional beamformers with an aperture that is at least 80 percent shorter while providing all the advantages of particle velocity measuring sensors such as left-right discrimination.