Scattering Effect on Array Gain of MVDR Beamforming of Conformal Array

In practice, the amplitude and phase of steering vectors of the array manifold matrix of conformal arrays can be distorted due to the influence of rigid scatterers such as baffles, which lead to the decrease of the array gain(AG) of the beamformer, and then to the loss of the sonar detection performance. In this paper, the performance of AG of minimum variance distortion response beamformers (MVDR) under the influence of scattering produced by the rigid baffle of the conformal array is simulated and discussed. An array manifold containing scattered signals is obtained by calculating sound field distribution on the surface of the conformal array using sound field prediction method. Then, the influence of scattering on AG of the MVDR beamforming is analysed. The simulation results show that the difference between the actual array manifold varies with the change of the azimuth due to the existence of scattering, which further leads to the change of the AG of the MVDR beamforming with the change of main lobe of the beam.