Ionospheric Inhomogeneities and Their Influences on the Earth’s Remote Sensing from Space

Abstract

An important problem that arises when planning experiments on remote sensing from space in the P-band is taking into account the influence of the Earth’s ionosphere. We investigated the influence of ionospheric inhomogeneities on the results of remote sensing of the Earth from space, taking into account the curvature of the propagation medium. One- and two-layer models of the ionosphere, both with and without large-scale inhomogeneities of the cold ionospheric plasma, were considered. To obtain numerical results, a bicharacteristic system was used, which makes it possible to adequately take into account the complex structures of ionospheric plasma layers. The dependence of the rate of phase change on the height and the dependence of the total electron concentration on the horizontal distance and group time were investigated. The case was compared when the vector of the strength of the Earth’s magnetic field is perpendicular to the plane of propagation, and the case when this vector lies in the plane of propagation. The dependence of the difference between the refractive indices on the height along the rays was studied. Estimates of the Faraday rotation angle and phase deviation were obtained for various models. The magnitude of the angle of Faraday rotation depends significantly on the orientation of the trajectory relative to the Earth’s magnetic field. Polarization coefficients are investigated. It is shown that the o- and x-waves are separately circularly polarized, and the contribution of the longitudinal component of the electric field in the electromagnetic wave is insignificant.