On radio wave propagation in multiscale randomly inhomogeneous ionosphere

Abstract

It is known that ionospheric irregularities have an adverse effect on radio wave propagation, especially in polar regions. The main feature of ionospheric irregularities is their multiscale character. Accordingly, various methods for describing radio wave propagation in media with large-scale and small-scale irregularities are developed. A number of papers have proposed a description of wave propagation in inhomogeneous media in a small-angle approximation in the form of Double-Weighted Fourier Transform (DWFT). Their findings are demonstrated to agree with the geometrical optics approximation, Rytov approximation, and phase screen method. This suggests that this approach can be used to describe wave propagation, simultaneously taking into account irregularities of different scales, including multipath propagation. In this paper, we employ the DWFT method to devise methods for describing radio wave propagation in the multiscale randomly inhomogeneous ionosphere. As an example of application of the DWFT method we consider ionospheric propagation of signals of global navigation satellite systems. Using the methods developed, we analyze the effect of irregularities of different scales on the behavior of mutual coherence function.