Ukrainian Antarctic journal

No 2 (2020): Ukrainian Antarctic Journal
Articles

An artificial neural network for analysis of ionograms obtained by ionosonde at the Ukrainian Antarctic Akademik Vernadsky station

O. Bogomaz
Institute of Ionosphere of the National Academy of Sciences of Ukraine, Kharkiv, 61001, Ukraine; State Institution National Antarctic Scientific Center, Ministry of Education and Science of Ukraine, Kyiv, 01601, Ukraine
M. Shulha
Institute of Ionosphere of the National Academy of Sciences of Ukraine, Kharkiv, 61001, Ukraine; State Institution National Antarctic Scientific Center, Ministry of Education and Science of Ukraine, Kyiv, 01601, Ukraine
D. Kotov
Institute of Ionosphere of the National Academy of Sciences of Ukraine, Kharkiv, 61001, Ukraine; State Institution National Antarctic Scientific Center, Ministry of Education and Science of Ukraine, Kyiv, 01601, Ukraine
A. Koloskov
Institute of Radio Astronomy of the National Academy of Sciences of Ukraine, Kharkiv, 61002, Ukraine;State Institution National Antarctic Scientific Center, Ministry of Education and Science of Ukraine, Kyiv, 01601, Ukraine
A. Zalizovski
Institute of Radio Astronomy of the National Academy of Sciences of Ukraine, Kharkiv, 61002, Ukraine;State Institution National Antarctic Scientific Center, Ministry of Education and Science of Ukraine, Kyiv, 01601, Ukraine; Space Research Centre of Polish Academy of Sciences, Warsaw, 00-716, Poland
Published December 29, 2020
Keywords
  • critical frequency,
  • deep learning,
  • electron density,
  • ionosphere,
  • pattern recognition

Abstract

The article presents the developed artificial neural network for F2 ionosphere layer traces scaling on ionograms obtained using the IPS-42 ionosonde installed at the Ukrainian Antarctic Akademik Vernadsky station. The parameters of the IPS-42 ionosonde and the features of the data obtained with it, in particular the format of the output files, are presented. The advantages of using an artificial neural network for identification of traces on ionograms are demonstrated. Usually, an automatic scaling of the ionograms requires a lot of machine time however implementation of an artificial neural network speeds up computations significantly allowing to process incoming ionograms even in the real time mode. The choice of architecture of an artificial neural network is substantiated. The U-Net architecture was chosen. The method of creating and training the neural network is described. The artificial neural network development process included choosing the number of layers, types of activation functions, optimization method and input layer size. Software developed was written in Python programming language with use of the Keras library. Examples of data used for training of the artificial neural network are shown. The results of testing an artificial neural network are presented. The data obtained with the artificial neural network are compared with the results of manual processing of ionograms. Data for training the artificial neural network were obtained in March, 2017 using the IPS-42 ionosonde installed at the Ukrainian Antarctic Akademik Vernadsky station; data for testing were obtained in 2017 and 2020. The developed artificial neural network has minor flaws but they are easily eliminated by retraining the network on a more representative dataset (obtained in various years and seasons). The general results of testing indicate good prospects in further developing this artificial neural network and software for working with it.