Imaging small three-dimensional elastic inclusions by an enhanced multiple signal classification method

Abstract

In this paper, an enhanced multiple signal classification (MUSIC) algorithm is introduced to retrieve small three-dimensional elastic inclusions. First, the multistatic response (MSR) matrix is built by two different ways depending on considering the multiple scattering effect or not. The eigenvalue structure of the MSR matrix is analyzed to identify the degenerate case of inclusions. Second, the pseudo-spectrum function is built with an optimal test direction on each node, where a balancing technique is employed to ensure the numerical stability. Benefitting from this MUSIC indicator, the degenerate inclusions can be located with a good performance against noise. Numerical simulations show the proposed method has wider applicability, better resolution, and more robust in the presence of noise than the standard MUSIC methods.