Fundamental limitations in antennas

  title={Fundamental limitations in antennas},
  author={Robert C. Hansen},
  journal={Proceedings of the IEEE},
  • R. Hansen
  • Published 1 February 1981
  • Business
  • Proceedings of the IEEE
Four fundamental limitations in antennas have been identified in the areas of: electrically small antennas, superdirective antennas, superresolution antennas, and high-pin antennas. All exhibit roughly exponential increase in cost factors with performance increase beyond the robust range. This paper reviews these limitations. Electrically small antennas are analyzed via spherical mode theory, with the antenna enclosed in a virtual sphere. Minimum Q varies inversely as the cube of sphere radius… 

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