A direction-sensitive model of atmospheric noise and its application to the analysis of HF receiving antennas
نویسنده
چکیده
[1] Global maps of lightning occurrence are combined with ray tracing propagation calculations to form a direction-sensitive model of atmospheric noise. The model suggests a very complex directional behavior that can vary strongly with location, time, season, sunspot number, and frequency. It is shown that the directional variability of noise, when coupled with the directional variability of antenna gain, can lead to marked changes in noise outcome between different antennas. The implication of directional varying noise for the optimum choice of receiver antenna is explored.
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