volume | PIER Journals

Abstract

The ground conductivity is the most important factor in the transmitter's coverage area in ground wave propagation. Regarding the day-to-day increase in digital broadcasting, a lower sensitivity of this kind of broadcasting and ability to create single frequency networks, it seems necessary to increase the accuracy of ground conductivity to minimize fading zones. The higher the abovementioned conductivity, the lower the ground wave attenuation. Also in this case, the transmitted wave will tilt less towards the ground to satisfy the boundary conditions in electric conductivity and so-called will enter the earth. In most of the presented papers to determine the field strength, conductivity is considered as known, but it's dependent upon the soil genus, the annual/monsoon precipitation and the heat average. Here it is intended to provide a new method based on Mie algorithm to determine the conductivity based on the difference of Horizontal Electric Dipole near the ground. The previous conductivity measurements included determining it in a point by point manner in a low frequency and determining the conductivity based on the coverage area intensity. The new method holds the two methods advantages together.

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Dr. S. Makki

Dr. Tohid Ershadi

Dr. Mohammad Abrishamian