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Antenna Properties and their impact on Wireless System Performance

Since the first demonstration of wireless technology in 1886 by Heinrich Hertz and its first practical radio application by Guglielmo Marconi in 1901, the antenna has been a key building block in the construction of wireless communications systems. In many instances, the antenna is not considered critical in the initial system design, however, it is the single device that allows RF energy to transition between wire transmission lines and free space. Since the days of Hertz, antennas have advanced from a simple wire dipole to more complex structures such as helical antennas, parabolic reflectors, Yagis, microstrip patch arrays, etc. The purpose of this article is to provide an overview of fundamental antenna properties, antenna performance characteristics, system RF propagation characteristics and related tradeoff issues. This article will also provide a discussion of how the antenna and RF propagation properties affect overall wireless system performance. This information can be used to establish antenna selection criteria for optimum system performance.