V. A. Nikolaev, T. G. Timasheva

In practical realizations antennas of a surface wave for reduction of losses at distribution of a surface wave the area between antennas by sea was metalize with the help of a ground reflector. The ground reflector were transform antenna-s elevation characteristics. In the result, maximum of antenna-s elevation characteristics were rise. In result, the radiation under the top corners of a place is increase and radiation along a surface was decrease. The estimation of influence the ground reflector on elevation characteristics is made with use of mathematical models of symmetric and asymmetrical antennas. Mathematical model of ground reflector were made of 32 radial wire, which set around. In model the ground reflector-s radius is 0,25λ; 0,50λ; 0,75λ; 1,0λ; 1,5λ; 2,0λ and  (perfect ground). The modeling results were showed on table and in the figure. The ground reflector-s influence on elevation characteristics of symmetrical antennas were less that this reflector-s influence on asymmetrical antennas. The data analysis were showed that minimal radius of reflector must be ~λ/4. The ground reflector was offered to cut on strips in width ~λ/4 for reduction of influence of a ground reflector by elevation characteristics

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