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… 
View via Publisher
dspace.mit.edu
1,890 Citations
Highly Influential Citations
171
Background Citations
863
Methods Citations
208
Results Citations
48

1,890 Citations

On the radiation Q and the gain of crossed electric and magnetic dipole moments

  • Do-Hoon Kwon
  • Business
    IEEE Transactions on Antennas and Propagation
  • 2005
Exact expressions for the radiation quality factor Q and the gain pattern function of the corresponding antenna are derived and their properties are analyzed for crossed electric and magnetic dipole…

On the radiation Q and the gain of crossed electric and magnetic dipole moments

Exact expressions for the radiation quality factor Q and the gain pattern function of the corresponding antenna are derived and their properties are analyzed for crossed electric and magnetic dipole…

Physical limitations of antennas in a lossy medium

  • A. Karlsson
  • Business
    IEEE Transactions on Antennas and Propagation
  • 2004
The dissipated power and the directivity of antennas in a homogeneous, lossy medium are systematically analyzed in this paper. The antennas are ideal and located inside a lossless sphere. In the…

On the Physical Limitations of the Interaction of a Spherical Aperture and a Random Field

This paper derives physical limitations on the interactions of antennas exciting TM or TE modes (but not both) and wireless propagation channels. The derivation is based on the spherical vector wave…

The folded dipole perspective of electrical small spherical helix antennas

  • J. W. KuoY.E. Wang
  • Business
    2008 IEEE Antennas and Propagation Society International Symposium
  • 2008
The dimensions of resonant antennas are typically in the same scale as the wavelength of the operating frequency. As the operating frequency decreases, the dimension of the antenna would increase…

Physical limitations on antennas of arbitrary shape

In this paper, physical limitations on bandwidth, realized gain, Q-factor and directivity are derived for antennas of arbitrary shape. The product of bandwidth and realizable gain is shown to be…

Antenna miniaturization beyond the fundamental limits using impedance modulation

  • M. Manteghi
  • Business
    2009 IEEE Antennas and Propagation Society International Symposium
  • 2009
Antennas which are physically smaller than their operative wavelength are defined as electrically small antennas. An electrically small antenna characterizes any antenna which fits insides a sphere…

Analysis of Pattern Gain of Compact Directional 16-port Antenna

Up to now, conventional compact antennas have been designed to acquire as much gain as an ideal 6-port polarimetric antenna can obtain. It was recently shown that an achievable number of degrees of…

Optimal Characteristics of an Arbitrary Receive Antenna

  • D. KwonD. Pozar
  • Mathematics
    IEEE Transactions on Antennas and Propagation
  • 2009
Several fundamental questions about the operation of receiving antennas are addressed, such as ldquoWhy does a receiving antenna scatter an incident field?rdquo and ldquoUnder what conditions does a…

Optimization of the Bandwidth of Electrically Small Planar Antennas

The bandwidth limitations of resonant, electrically small antennas that fully occupy a spherical volume are well defined by the inverse of the Chu-limit or the lower bound on quality factor.…
...

References

SHOWING 1-3 OF 3 REFERENCES

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.

A mathematical theory of linear arrays

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…