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Franke, Steven J. Raymund, Timothy Daniel 2011-05-07T13:22:04Z 2011-05-07T13:22:04Z 10000-01-01 1993 Recently, several tomographic techniques for ionospheric electron density imaging have been proposed. These techniques reconstruct a vertical slice image of electron density using total electron content data. The data are measured between a low orbit beacon satellite and fixed receivers located along the projected orbital path of the satellite. By using such tomographic techniques, it may be possible to inexpensively (relative to incoherent scatter techniques) image the ionospheric electron density in a vertical plane several times per day. The satellite and receiver geometry used to measure the total electron content data causes the data to be incomplete; that is, the measured data do not contain enough information to completely specify the ionospheric electron density distribution in the region between the satellite and the receivers. A new algorithm is proposed which allows the incorporation of other complementary measurements, such as those from ionosondes, and also includes ways to include a priori information about the unknown electron density distribution in the reconstruction process. The algorithm makes use of two-dimensional basis functions. Illustrative application of this algorithm is made to simulated cases with good results. The technique is also applied to real total electron content (TEC) records collected in Scandinavia in conjunction with the EISCAT incoherent scatter radar. The tomographic reconstructions are compared with the incoherent scatter electron density images of the same region of the ionosphere. Made available in DSpace on 2011-05-07T13:22:04Z (GMT). No. of bitstreams: 2 license.txt: 4922 bytes, checksum: 910b249b4beec47e7ab768910c8f966f (MD5) 9411761.pdf: 5672702 bytes, checksum: 05f4b2d687111338112c267c92b3ed0e (MD5) Previous issue date: 1993 Item marked as restricted to the 'UIUC Users [automated]' Group (id=2) by Howard Ding (hding2@illinois.edu) on 2011-05-07T14:53:50Z Item is restricted indefinitely. Restriction data tranferred 2014-07-01T11:24:57-05:00 Original Data Group with Access UIUC Users [automated] Release Date: none Reason: ETDs are only available to UIUC Users without author permission ETDs are only available to UIUC Users without author permission U of I Only AAI9411761 (UMI)AAI9411761 http://hdl.handle.net/2142/21882 eng Copyright 1993 Raymund, Timothy Daniel Geophysics Engineering, Electronics and Electrical Development and applications of ionospheric tomography text Electrical and Computer Engineering Electrical Engineering University of Illinois at Urbana-Champaign Dissertation Ph.D.