Accession Number : AD0685168

Title :   RAY-OPTICAL TECHNIQUES FOR WAVEGUIDE DISCONTINUITIES,

Corporate Author : POLYTECHNIC INST OF BROOKLYN FARMINGDALE N Y DEPT OF ELECTROPHYSICS

Personal Author(s) : Yee,Hung Yuet ; Felsen,Leopold B.

Report Date : JUN 1968

Pagination or Media Count : 193

Abstract : Ray methods are employed in connection with scattering by discontinuities in waveguides is analyzed in the work reported here. Since the notion of a ray is generally associated with the local propagating plane wave fields encountered at high frequencies, it is to be expected that ray solutions apply only when the wavelength is small compared with critical dimensions of a guiding or scattering structure. However, it is shown that even the low frequency regime can be accommodated with good accuracy, thereby making the ray-optical techniques a powerful tool for the study of waveguide scattering problems. To render a ray-method analysis useful, it is necessary to convert these fields into a sum of waveguide modes whose amplitudes furnish the modal reflection, transmission and coupling coefficients. This conversion can be accomplished systematically in parallel plane and circular regions. Reflection from the open ends of parallel plane waveguide is analyzed in detail. In the unflanged case, the ray results agree remarkably well with the exact solutions even for wavelengths as long as six times the width of the guide. Data are also presented for flanged terminations for which no exact solution is available. (Author)

Descriptors :   (*WAVEGUIDES, WAVE PROPAGATION), SCATTERING, ANOMALIES, DIFFRACTION, GEOMETRY

Subject Categories : Electrical and Electronic Equipment

Distribution Statement : APPROVED FOR PUBLIC RELEASE