Chaotic identification of HF radar waves echo

In order to further investigate HF radar waves echo chaotic characteristics, we study HF waves echo data. The correlation dimension and Kolmogorov entropy are calculated based on the phase space reconstruction theory. In the calculation of the correlation dimension, the fuzzy K-means algorithm is used to determine the scale-free range to improve the accuracy of the calculation. The value of the correlation dimension is fraction. According to the formula calculating K₂ entropy proposed by Grassberger and Procaccia, the Kolmogorov entropy is approximately calculated through estimating the K2 Entropy, and the value of Kolmogorov entropy is a limited positive. Then, HF radar waves echo is chaotic proved both correlation dimension and Kolmogorov entropy.