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Broadband Tuning Limits on UWB Antennas Based on Fano's Formulation

  • M. C. Villalobos
  • H. D. Foltz
  • J. S. McLean
  • I. Sen Gupta

The well-known limits on the radiation Q of electrically-small antennas do not lead to a straightforward, rigorous computation of wideband impedance matching limits, especially when higher-order spherical modes are used and higher-order tuning networks are permitted. Fano’s formulation of the wideband matching of arbitrary impedances does provide a rigorous solution, and has been previously applied to the lowest-order (TM01 or TE01) mode. In this paper we apply Fano’s theory to higher-order spherical modes. Graphs of numerical limits on high-pass and band-pass tuning versus size are presented.

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Copyright information

© Springer Science+Business Media, LLC 2007

Authors and Affiliations

  • M. C. Villalobos
    • 1
  • H. D. Foltz
    • 1
  • J. S. McLean
    • 2
  • I. Sen Gupta
    • 1
  1. 1.University of Texas -Pan AmericanUSA
  2. 2.TDK R&D CorporationUSA

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