Abstract:Using the multiplicative algebraic reconstruction technique(MART), the accuracy of ionospheric electron density in the cells without any rays traversing them depends on the initial value, which is generated by empirical model. To solve the above problem, an improved algebraic reconstruction technique is presented in the paper. In this algorithm, a basic scale is calculated as the proportion of observed STEC and reconstructed STEC in some iteration. According to the spatial correlation of electron density, scaling factors are calculated as a function of basic scale and the distance from the center of cell and GPS ray for each cell in the reconstruction area. So, the ionospheric electron density of each cell will get closer to the ground truth. Numerical experimental and actual observation tests prove that the new algorithm is superior to the original MART.