Array gain of an eigenvalue beamformer in a continental slope waveguide

The acoustic environment of the continental shelf slope waveguide is more complex than those with flat bottoms. For a long receiving array in this area, the amplitude and phase of the received signals will be distortional, leading an attenuation in the spatial correlation of the sound field and a degradation in the array gain of beamformers. This paper shows the performances of three beamformers: the conventional beamformer (CBF), the minimum variance distortionless response beamformer (MVDR-BF) and the eigenvalue beamformer (EBF) by means of the array gain in the continental shelf slope waveguide, via theoretical analyses and computer simulations. A horizontal uniform linear array (ULA) with a wide-aperture in the slope region receiving signals from a shallow water source is considered. The array gains of CBF, MVDR-BF and EBF are compared, and the results show that EBF demonstrates higher array gains compared to CBF and MVDR-BF.