|
Read Full Article (file size: 1390168 bytes) Cited by
RADIO SCIENCE,
VOL. 43,
RS3001,
doi:10.1029/2007RS003716,
2008
Three-dimensional tomography of ionospheric variability using a dense GPS receiver array
Jeffrey K. Lee
Department of Electrical and Computer Engineering and the Coordinated Science Laboratory, University of Illinois at Urbana-Champaign,
Urbana, Illinois, USA
Farzad Kamalabadi
Department of Electrical and Computer Engineering and the Coordinated Science Laboratory, University of Illinois at Urbana-Champaign,
Urbana, Illinois, USA
Jonathan J. Makela
Department of Electrical and Computer Engineering and the Coordinated Science Laboratory, University of Illinois at Urbana-Champaign,
Urbana, Illinois, USA
Abstract
This paper investigates the localized 3D imaging of equatorial ionospheric depletions and mesoscale traveling ionospheric
disturbances (MS-TIDs) with a dense ground-based GPS receiver array. A tomographic forward model is presented using dual-frequency
GPS measurements from receivers in the Japanese GPS Earth Observation Network (GEONET). The application of inversion techniques
to the discrete observation matrix allows a 3D electron density volume to be reconstructed from the GPS total electron content
(TEC) measurements. Because the inverse problem is ill-posed and ill-conditioned, regularization functionals are used to constrain
the solution in the presence of noise. To capture the abrupt height and density variations of the structures, a technique
using nonconvex penalty constraints is proposed. The reconstructions have 40 to 50-km horizontal and 30-km vertical resolution.
Time series of reconstructed images show the evolution and movement of ionospheric structures through the reconstruction region.
The results are analyzed and compared with independent ionosonde measurements and vertical TEC (VTEC) maps constructed from
the observed GPS data.
Received 26
June
2007;
accepted 26
February
2008;
published 6
May
2008.
Keywords: ionospheric tomography;
GPS;
inverse problem.
Index Terms: 6982 Radio Science: Tomography and imaging (7270, 8180); 3260 Mathematical Geophysics: Inverse theory; 2435 Ionosphere: Ionospheric disturbances; 2443 Ionosphere: Midlatitude ionosphere; 6974 Radio Science: Signal processing (0674).
Read Full Article (file size: 1390168 bytes) Cited by
Citation: Lee, J. K., F. Kamalabadi, and J. J. Makela
(2008),
Three-dimensional tomography of ionospheric variability using a dense GPS receiver array,
Radio Sci.,
43,
RS3001,
doi:10.1029/2007RS003716.
Copyright 2008 by the American Geophysical Union.
|