Direct image reconstruction for electromagnetic tomography by using the factorization method

A factorization method was introduced to electromagnetic tomography (EMT) in this paper. Compared with the traditional methods based on the sensitivity theorem, the proposed method can generate the reconstructed images directly. Neither matrix inversion nor iterations is needed in the reconstruction process. The reconstruction process is simple, as the test function is calculated according to the fundamental solution to the governing equation, i.e. the Helmholtz equation. Simulated data were used to validate the feasibility and effectiveness of the proposed method for EMT.