Ionospheric tomography systems exhibit very poor vertical resolution. The algorithm presented in this paper is one that improves the vertical resolution of the reconstruction by using separable basis functions, where the vertical component is based upon a priori information. However, even with a priori information, the poor vertical resolution of the imaging system results in poor numerical conditioning of the reconstruction problem. The RCM algorithm divides the poorly conditioned problem into several smaller well-conditioned problems. The smaller problems are then solved separately for an approximate solution, and iteration is used to improve the approximation.
Acknowledgments: This material is based upon work supported by the National Science Foundation under grant ATM-9211708 and grant ATM-9419552.