Application of computerized tomography to the investigation of ionospheric structures

It is shown that ionospheric total electron content measurements, obtained simultaneously at several locations, can be processed using computerized tomography (CT) algorithms to obtain two-dimensional images of ionospheric electron density. CT, using ionospheric total electron content data, is applied to simulate density variations over 16 deg of latitude and a height range of 50 to 1000 km. A method of approximating the peak height and scale height of the electron density profile is presented, as well as a reconstruction technique using a multiplicative algebraic algorithm and a back projection based initial guess. The quality of the images is examined for two geometries and resolutions. It is suggested that the reconstruction algorithm is sufficiently robust to perform well even in the presence of broad-band noise of reasonable level. 12 refs