Determination of the vertical electron-density profile in ionospheric tomography: experimental results

• Published in: Annales Geophysicae
• Main Authors: Mitchell, C. N., Kersley, L., Heaton, J. A. T., Pryse, S. E.
• Format: Article in Journal/Newspaper
• Language: English
• Published: Springer Verlag 1997
• Subjects: article; Verlagsveröffentlichung; EISCAT
• Online Access: https://doi.org/10.1007/s00585-997-0747-1; https://noa.gwlb.de/receive/cop_mods_00037553; https://noa.gwlb.de/servlets/MCRFileNodeServlet/cop_derivate_00037507/angeo-15-747-1997.pdf; https://angeo.copernicus.org/articles/15/747/1997/angeo-15-747-1997.pdf

The reconstruction of the vertical electron-density profile is a fundamental problem in ionospheric tomography. Lack of near-horizontal ray paths limits the information available on the vertical profile, so that the resultant image of electron density is biased in a horizontal sense. The vertical profile is of great importance as it affects the authenticity of the entire tomographic image. A new method is described whereby the vertical profile is selected using relative total-electron-content measurements. The new reconstruction process has been developed from modelling studies. A range of background ionospheres, representing many possible peak heights, scale heights and electron densities are formed from a Chapman profile on the bottomside with a range of topside profiles. The iterative reconstruction process is performed on all of these background ionospheres and a numerical selection criterion employed to select the final image. The resulting tomographic images show excellent agreement in electron density when compared with independent verification provided by the EISCAT radar.