Summary: | 碩士 === 國立成功大學 === 電機工程研究所 === 82 === In VHF air/ground communication systems, the radio-line- of-
signt (RLOS) between a ground station and an aircraft must
exist. An aircraft at a certain altitude may be interfered by
those signals from over-horizontal stations using the same
frequency band. A simple frequency management method is
proposed in this paper to solve this problem and to get the
efficient frequency-reuse to alleviate the frequency congestion
in air traffic control (ATC), flight services and mobile
communication services. We apply the concept of the terrestrial
mobile cellular system to design the 3D cellular systems and
find the capacities of systems with different access schemes,
such as interference free, FDMA, TDMA, and CDMA.
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