Abstract
In this paper we apply a method based on empirical orthogonal function (EOF) analysis to automatically scale the F2-layer parameters obtained from ionograms. For a given location, the F layer’s height profiles of ionospheric electron density are represented as an EOF series with adjustable coefficients derived from the EOF analysis of electron density profiles obtained from the International Reference Ionosphere (IRI-2001) model or measured ionograms. By adjusting the coefficients of the series and combining image matching technique, we were able to construct a calculated trace that approximates as close as possible the observed ionogram F2 trace. The corresponding parameters are then known, including the critical frequency (foF2), peak height (hmF2) and maximum usable frequency [MUF(3000)F2] of the F2 layer. Polarization information is unnecessary; only an amplitude array is essential. Consequently, this method is universal and can be applied to many kinds of ionograms (even the film ionograms after an appropriate conversion of the information to the digital form from the film ionogram). To evaluate the acceptability of the obtained parameters, large numbers of foF2, hmF2 and MUF(3000)F2 values from the manually scaled ionograms at Wuhan (114.4°E, 30.5°N), China are compared with those from automatically scaled ionograms by the Automatic Real Time Ionogram Scaler with True height (ARTIST) and our method. The results indicate that the scaled parameters are acceptable and stable.
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Daniell, R. E., L. D. Brown, D. N. Anderson, M. W. Fox, P. H. Doherty, D. T. Decker, J. J. Sojka, and R. W. Schunk, Parameterized ionospheric model: a global ionospheric parameterization based on first principles models, Radio Sci., 30, 1499–1510, 1995.
Fox, M.W. and C. Blundell, Automatic scaling of digital ionograms, Radio Sci., 24, 747–761, 1989.
Galkin, I. A., B. W. Reinisch, G. Grinstein, G. Khmyrov, A. Kozlov, X. Q. Huang, and S. Fung, Automated exploration of the radio plasma imager data, J. Geophys. Res., 109, A12210, doi: 10.1029/2004JA010439, 2004.
Huang, X. Q. and B. W. Reinisch, Automatic calculation of electron density profiles from digital ionograms, 2. True height inversion of topside ionograms with the profile-fitting method, Radio Sci., 17, 837–844, 1982.
Huang, X. Q. and B.W. Reinisch, Vertical electron content from ionograms in real-time, Radio Sci., 36, 335–342, 2001.
Huang, X. Y., Y. Z. Su, and K. Zhang, Ionospheric structure and profile over Wuchang, China, Adv. Space Res., 15, 149–152, 1995.
Mather, P. M., Computer Processing of Remotely Sensed Images: An Introduction, 2nd Edition Wiley, Chichester, 292 pp., 1999.
Mazzetti B. and G. E. Perona, Automatic analysis of diurnal digital ionograms, Alta Frequenza, 47, 495–500, 1978 (in Italian).
Pezzopane M., Interpre: AWindows software for semiautomatic scaling of ionospheric parameters from ionograms, Computers Geosci., 30, 125–130, 2004.
Reinisch, B. W. and X. Q. Huang, Automatic calculation of electron density profiles from Digital ionograms, 3. Processing of bottomside ionograms, Radio Sci., 18, 477–492, 1983.
Reinisch, B. W., X. Q. Huang, I. A. Galkin, V. Paznukhov, and A. Kozlov, Recent advances in real-time analysis of ionograms and ionospheric drift measurements with digisondes, J. Atmos. Solar Terr. Phys., 18, 477–492, 2005.
Scotto, C., A Method for Processing Ionograms Based on Correlation Technique, Phys. Chem. Earth., 26, 367–371, 2001.
Storch, H. V. and F. W. Zwiers, Statistical Analysis in Climate Research, Cambridge University Press, 2002.
Titheridge, J. E., The real height analysis of ionograms: a generalized formulation, Radio Sci., 23, 831–837, 1988.
Tsai, L. C. and F. T. Berkey, Ionogram analysis using fuzzy segmentation and connectedness techniques, Radio Sci., 35, 1173–1186, 2000.
Wang, X., J. Shengyun, and X. Dilong, EoFs analytic representation of the ionospheric electron density profile, Chinese Journal of Radio Science, 19(5), 560–564, 2004.
Weare, B. C. and J. S. Nasstron, Example of extended empirical orthogonal function analysis, Mon. Weather Rev., 110, 281–485, 1982.
Wright, J. W., A. R. Laird, D. Obitts, E. J. Violette, and D. McKinnis, Automatic N(h,t) profiles of the ionosphere with a digital ionosonde, Radio Sci., 7, 1033–1043, 1972.
Zhao, B., W. Wan, L. Liu, X. Yue, and S. Venkatraman, Statistical characteristic of the total ion density in the topside ionosphere during the period 1996–2004 using empirical orthogonal function (EOF) analysis, Ann. Geophys., 23, 3615–3631, 2005.
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Ding, Z., Ning, B., Wan, W. et al. Automatic scaling of F2-layer parameters from ionograms based on the empirical orthogonal function (EOF) analysis of ionospheric electron density. Earth Planet Sp 59, 51–58 (2007). https://doi.org/10.1186/BF03352022
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DOI: https://doi.org/10.1186/BF03352022