Wideband MVDR beamforming for acoustic vector sensor linear array

A wideband minimum variance distortionless response (MVDR) beamforming approach for an acoustic vector sensor linear array is presented, which is based on coherent signal subspace preprocessing, to solve the problem of direction of arrival (DOA) estimation for wideband coherent acoustic sources. The concept of wideband focusing is introduced into wideband processing for the acoustic vector sensor array, and the relationship between the wideband focusing matrices of the acoustic vector sensor array and the pressure sensor array is derived. Simulation results show that wideband MVDR beamforming of an acoustic vector sensor linear array outperforms that of a pressure sensor when dealing with wideband coherent sources, in the following aspects: realising unambiguous direction finding in the whole space, i.e. no left/right ambiguity problem; allowing the uniform interelement spacing to exceed the Nyquist half-wavelength upper limit; and having a better performance for DOA estimation when dealing with sources close to endfire.