In this work,the ray trajectory for oblique incidence is determined by solving the wave equation using the Finite Element Method (FEM). In case of ionospheric reflection the Discrete Fourier Transform (DFT), applied here in the space domain, is used to discriminate the incident and reflected waves. Ray tracing equations are combined with the Poynting vector components in order to calculate the wave trajectory taking into account the Earth's curvature. The results are illustrated for different frequencies and angles of incidence using electron density profiles obtained from the Rome digisonde station,topside profiles from the IRI-95 model and atmospheric data from the MSIS-E-90 model of NSSDC as an inputs.
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