volume | PIER Journals

Abstract

In this paper, the propagation of electromagnetic rays in a tropospheric waveguide and spatial processing using digital antenna arrays are studied. The beam traveling through the layers of the atmosphere depends on the refractive index and its vertical change. In this regard, conditions may arise when radio rays propagate in a waveguide manner at low altitudes. In this case, attenuation takes place, and the effect of multipath fading may also occur, when several rays reflected from different layers of the troposphere and with various spatial coordinates in elevation arrive at the receiver. It is proposed to apply digital antenna arrays to increase the range and reliability of radio communication through the tropospheric waveguide. Parabolic equations are utilized to estimate the path loses of radio waves of the centimeter wavelength. A ray-tracing algorithm via a tropospheric waveguide is used to estimate the mutual phases in the aperture of the receiving array. Bit error rate curves were obtained depending on the geometry of the antenna arrays after the signal passed through the tropospheric waveguide.

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Dr. Ilia Peshkov