Direct recovery of the electrical admittivities in 2D electrical tomography by using Calderon's method and two-terminal/electrode excitation strategies

Calderon's method was used to reconstruct electrical admittivity, i.e. conductivity as well as permittivity, for electrical tomography in this paper. It is a direct algorithm of the image reconstruction, as the value of the real and imaginary parts of the admittivity at any position can be obtained independently. A new way to construct the Dirichlet-to-Neumann map from the data collected through two-terminal/electrode excitation strategy was also introduced to calculate the scattering transform. The image reconstruction was implemented through numerical integration. Since the Gauss–Legendre quadrature was applied and can be predetermined, the image reconstruction process was fast and resulted in images of good quality. Both simulated and experimental results validated the feasibility and effectiveness of the proposed method in dual-modality electrical tomography.