| 摘要 |
In one embodiment, a horizontal antenna is mounted electrically separated from but near the top of a vertical antenna. For a given wattage and frequency and for two stations separated a known distance apart, the proscribed angle of elevation for ionospheric reflection for each station can be computed. The current and phase of the signal applied to the horizontal antenna can be adjusted to cancel the electromagnetic field waves emitted from the vertical antenna in the selected azimuth and angle of elevation. The cancellation effects waves of a certain angular orientation at the proscribed angle of elevation for ionospheric reflection.
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