Simulation Research on Evaluation of EIT Image Reconstructed by Different Algorithms

Reconstruction algorithm is always the important area of electrical impedance tomography (EIT). Aiming at target with different depths, using 3 algorithms, equipotential lines back projection algorithm (ELBP), conjugate gradient algorithm (CG) and Newton-Raphson algorithm (NR), simulation evaluation has been carried out. Reconstruction quality function D which reflects the error between imaging model and reconstructed image, and structure deviation degree function SSIM which reflects structure distortion of reconstructed image, are adopted for the quantitative evaluation of reconstructed image by 3 algorithms. The results of the simulation evaluation show that the reconstruction error of ELBP algorithm is the lowest among 3 algorithms, CG algorithm and NR algorithm have lower structure distortion and higher locating capability than that by ELBP. From the perspective of reconstruction error and structure distortion, D and SSIM commendably reflect the information of reconstructed image, as well as the advantages and disadvantages of 3 algorithms. The function D and SSIM provide impersonal, effective evaluation methods and adaptive for the image characteristic of EIT.