A new method of ionospheric tomographic reconstruction

Adaptive simultaneous iteration reconstruction technique is a fast algorithm for the tomographic reconstruction of ionospheric electron density distribution. However, the algorithm is sensitive to the initial value. For those cells without any rays traversing them, the final results are the same as the initial values, which are obtained from empirical ionospheric model. To resolve the above problem, a constrained adaptive simultaneous iteration reconstruction technique is presented in this paper. The new method imposes reasonable constraints on the tomography system by considering the continuousness and smoothness of neighboring cells, and the accuracy of ionospheric electron density reconstruction is efficiently improved. Numerical test and actual GNSS observation experiment validates the feasibility and superiority of the new method.