High-frequency signal propagation and scattering in guiding channels

  • L. B. Felsen
Classical Scattering Theory
Part of the Lecture Notes in Physics book series (LNP, volume 130)


The earth's environment contains propagation channels wherein waves can be guided because of the presence of transverse boundaries or transverse refractive index gradients. By a new approach, high-frequency guiding by a single concave surface or by the boundary of an inhomogeneous surface duct has recently been analyzed in terms of a judiciously chosen combination of rays and modes. In essence, the modes account for the cumulative effect of those rays that have experienced a great many reflections on the boundary. This hybrid formulation is appealing in that it requires far fewer rays and far fewer modes than if the field representation involves rays only or modes only, as has been customary. By an extension of the theory, it has now been shown that the hybrid method can also be applied to channels wherein guiding occurs between multiple transverse boundaries. Here, modes near cutoff can represent efficiently all those rays that have made many excursions between the channel walls. As an illustration, results are presented for a parallel plane waveguide excited by a line source.


Line Source Waveguide Mode Hybrid Formulation Whisper Gallery Mode Evanescent Mode 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.


Unable to display preview. Download preview PDF.

Unable to display preview. Download preview PDF.


  1. [1]
    T. Ishihara, L. B. Felsen: “High frequency fields excited by a line source located on a concave cylindrical impedance surface,” IEEE Trans. AP-27, 172–179 (1979)Google Scholar
  2. [2]
    L. B. Felsen, T. Ishihara: “Hybrid ray-mode formulation of ducted propagation”, J. Acoust. Soc. Am. 65, 595–607 (1979)Google Scholar
  3. [3]
    A. Kamel, L. B. Felsen: “Hybrid ray-mode representation of the high-frequency parallel plane waveguide Green's function,” in preparationGoogle Scholar
  4. [4]
    L. B. Felsen, N. Marcuvitz: Radiation and Scattering of Waves (Prentice Hall, Englewood Cliffs, New Jersey, 1973), Chap. 4Google Scholar
  5. [5]
    D. V. Batorsky, L. B. Felsen: “Ray optical calculation of modes excited by sources and scatterers in weakly inhomogeneous ducts,” Radio Science 6, 911–923 (1971) *** DIRECT SUPPORT *** A3418088 00004Google Scholar

Copyright information

© Springer-Verlag 1980

Authors and Affiliations

  • L. B. Felsen
    • 1
  1. 1.Department of Electrical EngineeringFarmingdaleNew York

Personalised recommendations