An Empirical Investigation of High-frequency Ground Wave Propagation
نویسنده
چکیده
Under the sponsorship of the Defense Nuclear Agency, The Johns Hopkins University Applied Physics Laboratory investigated high-frequency ground wave propagation as a nuclear-survivable means of communication for land-mobile missile systems in Europe. Using a frequency band of 20 to 30 MHz and a portable, broadband, discone antenna, high-frequency ground wave propagation characteristics have been demonstrated that could be exploited in communication systems. Test results show that with such antennas, the upper part of the high-frequency band could be used to achieve non-line-of-sight, nonfading, communication over short-range paths for both military and civilian applications.
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