Physical Limitations of Omni‐Directional Antennas

@article{Chu1948PhysicalLO,
  title={Physical Limitations of Omni‐Directional Antennas},
  author={Lan Jen Chu},
  journal={Journal of Applied Physics},
  year={1948},
  volume={19},
  pages={1163-1175}
}
  • L. J. Chu
  • Published 1 December 1948
  • Business
  • Journal of Applied Physics
The physical limitations of omni‐directional antennas are considered. With the use of the spherical wave functions to describe the field, the directivity gain G and the Q of an unspecified antenna are calculated under idealized conditions. To obtain the optimum performance, three criteria are used, (1) maximum gain for a given complexity of the antenna structure, (2) minimum Q, (3) maximum ratio of G/Q. It is found that an antenna of which the maximum dimension is 2a has the potentiality of a… 

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Optimum Current Distributions on Vertical Antennas

The theoretical optimum current distribution on a vertical antenna of given length is defined as that current distribution giving the maximum possible field strength on the horizon for a given power

The problem of optimum antenna current distribution

The final author version and the galley proof are versions of the publication after peer review that features the final layout of the paper including the volume, issue and page numbers.

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A MATHEMATICAL theory, suitable for appraising and controlling directive properties of linear antenna arrays, can be based upon a simple modification of the usual expression for the radiation