Pilar Jarabo Amores, Jesús Alpuente Hermosilla,
نویسنده
چکیده
– In this paper we describe a method for designing broadcasting HF communication systems capable of accomplishing wide coverage using reduced power transmitters. Given a set of available frequencies and the transmitters maximum power, we provide the frequencies subset that must be used for different time intervals, during each month of the year for a given solar activity. This method is based on an overlapping coverage concept in order to meet the system specifications. After defining a suitable grid over the desired coverage, we will apply a numerical model of the ionosphere to the prediction of the short wave ionospheric circuits that can be established between each grid point and the transmitters emplacement. Then an iterative process is proposed for selecting the set of frequencies that will accomplish the desired reliability. This method has been used giving rise to an optimum solution in terms of transmitter power and antenna gain.
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