Characteristics of radio signal distortions in an inhomogeneous linear plasma layer

A strict solution of the problem of dispersion distortion of AM and FM radio pulses in an inhomogeneous linear plasma layer is used for an asymptotic and numerical study of the problem. The characteristics of space-time focusing of an FM pulse field related to the formation of singular space-time caustics are studied. Numerical calculations of the strict solution are carried out with the aid of the fast Fourier transform and are compared with results obtained by asymptotic methods, namely, the method of space-time geometrical optics and the time integral representation.