Robust Constant-beamwidth Beamforming Based on Focusing Approach for Acoustic Imaging

Focused beamformer is an efficient broadband beamforming method due to the advantages like ability to operation in multipath environments and computational efficiency. However, the robustness of focused beamformer is not enough. To overcome the shortcoming, a novel robust broadband beamforming method based on focusing approach is presented in this paper to achieve constant beamwidth for acoustic imaging. The proposed method mainly combines the idea of robust Capon beamforming (RCB) in the focusing approach to get the more exact focusing transformation matrix and then reduce the focused data error. Thus it can greatly improve the robustness performance of focused beamformer. Simulation results show the feasibility of the proposed method