High resolution ionospheric tomography through orthogonal decomposition

Using data from several ground stations tracking a single satellite pass, the methods of computerized tomography can be used to construct images that show a cross section of ionospheric electron density. Due to physical limitations of the imaging system, the images obtained when traditional computerized tomography algorithms are applied to the ionospheric tomography problem exhibit very poor vertical resolution. However, the vertical resolution can be improved through the use of a priori information. The paper presents a new method of introducing a priori information into the reconstruction algorithm using orthogonal decomposition. The central idea presented is to constrain the image space in such a way as to limit the vertical distribution of the reconstructed image to a space consisting of distributions based on a priori information, while allowing the horizontal distribution to vary with as much freedom as possible