Theorems on Time-Domain Far Fields

  • Arthur D. Yaghjian
  • Thorkild B. Hansen


The far-field characteristics of classical electromagnetic fields satisfying Maxwell’s equations have been investigated quite thoroughly for sources radiating at a single frequency, that is, for frequency-domain or time-harmonic fields [1]. For example, frequency-domain far fields radiated by integrable sources in a volume of finite extent decay as 1/r or faster as the distance r to the far field approaches infinity. In addition, these far fields are entire analytic functions of their angular variables θ and ø. Using a plane-wave decomposition, frequency-domain near fields can be expressed as an integral of the far-field pattern and its analytic continuation to complex angles of observation [2],[3].


Point Charge Finite Time Interval Finite Region Finite Extent Entire Analytic Function 
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Copyright information

© Springer Science+Business Media New York 1997

Authors and Affiliations

  • Arthur D. Yaghjian
    • 1
  • Thorkild B. Hansen
    • 1
  1. 1.RL/ERCSHanscom AFBUSA

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