Classification of Statistical Channel Models for Local Multipoint Distribution Service Using Antenna Height and Directivity
نویسندگان
چکیده
Abstract The antenna height and directivity are used in the classification of statistical channel models for local multipoint distribution service (LMDS). When directional antennas are used and the antennas are sufficiently high providing a line-of-sight (LOS) propagation path between the transmitter and receiver, the statistics of the radio channel can be described by the lognormal or Nakagami-m distribution. The channel statistics fits the Rician distribution, if omni-directional antennas are used. The directivity of antennas sets the direction of arrival signals and limits the number of propagation paths. When omni-directional antennas are used and at least one of the antennas is lower than the surrounding obstacles, and hence an LOS propagation path is absent, the radio channel is described by the statistics of the Rayleigh distribution. The above-mentioned channel models can be used to evaluate the performance of LMDS systems.
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