Nonlinear time series analysis of the ionospheric measurements

作     者：Karpenko, AL Manaenkova, NI 

作者机构：1. Institute of Terrestrial Magnetism Ionosphere and Radio Wave Propagation IZMIRAN 142092 Troitsk Moscow Region Russia 

出 版 物：《GEOLOGISCHE RUNDSCHAU》 (国际地球科学杂志)

年 卷 期：1996年第85卷第1期

页      面：124-129页

核心收录：

学科分类：07[理学] 0708[理学-地球物理学] 

主　　题：ionosphere irregularities radiowave propagation ionosonde ionogram attractor fractal dimension correlation algorithm Liapounov exponent 

摘      要：The applications of the tools of nonlinear time-series analysis to measurements obtained by digital ionosonde PARUS, created at IZMIRAN, is considered. Small-scale structure of the electron density Ne at F-region of ionosphere is examined by exploring observables of reflected high-frequency radio wave. Time series corresponding to given transmitter frequency f and virtual height h and conforming to usual, not perturbed, day ionogram are examined. Using the standard correlation algorithm, we have determined that for an embedding dimension n=15, computed correlation dimension D2(n) reaches its saturation, D2 congruent to 4. Reliability of the estimation of the correlation dimension was confirmed by applying to our sets of measurements J. Theiler s modification of standard algorithm. The test of time difference, smoothing procedure, calculation of the largest Liapounov exponent, and analysis of the surrogate data were employed in our study of data sets. Although our sets of measurements contain a significant random noise , nonlinear time-series analysis clear up, that the dynamics of unperturbed ionosphere, generating this time series, exhibits low-dimensional behavior.