Summary
A problem of propagation of modulated high-frequency signals in a waveguide of nonconstant height and nonconstant wall impedance is analysed. A multiple-scale method is used, which reduces the three-dimensional problem to a twodimensional problem for each mode. The modal propagation problem is analysed by the ray method, giving rise to phase and group velocities, and showing the possibility of focusing effects due to variation in height and wall impedance. Mode coupling effects are shown and mode coupling coefficients calculated.
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This work was done while the author was visiting at the Department of Mathematics, Rensselaer Polytechnic Institute, Troy, New York, and was supported by NSF Grant No. GU 2605.
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Rulf, B. Propagation in the earth-ionosphere waveguide by the multiscaling method. J Eng Math 8, 141–148 (1974). https://doi.org/10.1007/BF02353616
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DOI: https://doi.org/10.1007/BF02353616