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Study on Neutral Networks of Ionosphere Delay Corrections of Satellite Altimeters

Ionosphere is part of the upper atmosphere of the Earth, research of ionosphere model is meaningful to reduce ionosphere delay on microwave signals. In this paper, the Back Propagation (BP) model was designed with data of Jason-2 altimeter from 2008 to 2018. The inputs of the model are year, day of the year, hour of the day, latitude and longitude, and the output is the double-frequency correction of the ionosphere. The best model is obtained by repeated training. The selected best model is validated with four cycles of Jason-3. The results show that the mean differences between the model and target of four cycles are between -0.2 and 0.06cm, the standard deviations are less than 1cm, the differences of 95% are located between ± 2cm, the correlation coefficients are all above 0.7. The result indicates that BP model is efficient for the correction of ionosphere delay and with a high accuracy.