Total electron content (TEC) forecasting by Cascade Modeling: A possible alternative to the IRI-2001

Senalp, Erdem Turker
Tulunay, Ersin
Tulunay, Yurdanur
The ionospheric parameter, total electron content (TEC)is one of the key parameters in navigation and telecommunication applications. A small group at METU in Ankara has been developing data driven models in order to forecast the ionospheric parameters since 1990. In particular, results on forecasting TEC values one hour in advance by using their Neural Network Model - METU-NN have been reported previously. Since then, some work has been done in order to increase the performance of the METU-NN. In this paper, the most recent advanced model of the Neural Network containing Cascade Modeling (METU-NN-C) based on the Hammerstein systems is introduced. To demonstrate the performance of the METU-NN-C model, the Chilbolton and the Hailsham TEC values are considered during severe Space Weather conditions in some periods of 2001 and 2002. The authors have considered the METU-NN-C model as an alternative to the IRI-2001. In order to facilitate a comparison, IRI-2001 Hailsham TEC values are compared with those of the METU-NN- C by taking observed values as a basis.


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Performance of IRI-based ionospheric critical frequency calculations with reference to forecasting
ÜNAL, İBRAHİM; Senalp, Erdem Turker; YEŞİL, ALİ; Tulunay, Ersin; Tulunay, Yurdanur (American Geophysical Union (AGU), 2011-01-27)
Ionospheric critical frequency (foF2) is an important ionospheric parameter in telecommunication. Ionospheric processes are highly nonlinear and time varying. Thus, mathematical modeling based on physical principles is extremely difficult if not impossible. The authors forecast foF2 values by using neural networks and, in parallel, they calculate foF2 values based on the IRI model. The foF2 values were forecast 1 h in advance by using the Middle East Technical University Neural Network model (METU-NN) and t...
Citation Formats
E. T. Senalp, E. Tulunay, and Y. Tulunay, “Total electron content (TEC) forecasting by Cascade Modeling: A possible alternative to the IRI-2001,” RADIO SCIENCE, pp. 0–0, 2008, Accessed: 00, 2020. [Online]. Available: