Numerical modeling and comparative analysis of the effects of ionosphere and precipitation on microwave propagation in Ku and Ka bands

Document Type : Research

Authors
10.22034/jmrph.2026.137443.0
Abstract
Given the plasma nature of the ionosphere, the effect of ionospheric parameters, especially the total electron content (TEC), on the phase shift and Faraday rotation of the waves was evaluated. The International Ionospheric Reference Model (IRI) was used to describe the ionospheric conditions, and the ERA5 reanalysis data provided by the European Centre for Medium-Range Weather Forecasts (ECMWF) was used to consider atmospheric conditions. Also, the computational relations related to signal attenuation in satellite links were implemented in a computational framework in Python based on the ITU R P.838 recommendation. The results show that in the Ku band, due to the lower frequency, ionospheric effects, including signal phase shift, are significant; while in the Ka band, these effects are significantly reduced due to their dependence on the inverse of the frequency and, in the case of some parameters, on the inverse of the square of the frequency. The results also show that due to the lower latitude of Bandar Abbas, the TEC values ​​and consequently the ionospheric effects in this region are higher than in Tehran. However, the analysis of the results indicates that in the Ka band, the attenuation due to precipitation can reach values ​​of more than 10 dB, which is one of the main challenges in the design of satellite communication links in this band. Overall, the results of this study show that choosing the appropriate frequency band for satellite links requires balancing the effects of ionospheric disturbances and attenuations caused by atmospheric phenomena.
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