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Contents
Summary
This chapter has presented an introductory overview of groundbased
tomography. It has investigated the resolution and error sensitivity
of a twodimensional tomographic system and found that the full width
at half maximum of the point spread function
varies from 4 km at 120 km altitude to 10 km at 210 km altitude for an
input point with side lengths of 2 km. It was discovered that the full width at 10 % of
maximum was smeared out to all altitudes in the vertical
direction. Together with the error sensitivity of the
problem this implies that the result of the tomographic inversion cannot
retrieve fine scale internal structures. However, estimates of the
spatial distribution of ionospheric emissions which, in general, have
a comparatively simple shape, can be accurately obtained.
A strengthening of the statistical stopping criteria by
Veklerov and Llacer (1989a) is presented.
copyright Björn Gustavsson 20001024
