Antenna Effects on Hf Systems
نویسندگان
چکیده
In the HF band (3-30 MHz), the equipment used for transmission or for location finding, rely on the antenna system which can be very varied, using antenna diversity and/or space diversity. The roles of these antennas or antenna arrays are presented in this paper using a bi-vectorial model related to ionospheric links. This narrow band model includes propagation effects, transmitting and receiving antennas effects via their complex responses and the characteristics of the link geometry. After a quick description and analysis of the model, typical applications are shown in the fields of direction finding, simulators, channel analysis and digital transmissions.
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