An error in the geometrical theory of diffraction (GTD) near-field analysis of a conical horn published earlier is pointed out. This error is corrected, and the correct expression for the near-field patterns for the conical horn is presented. Computations based on the corrected formulas correlate better with results based on measurement as well as aperture integration technique [4]. Copyright © 1982 by The Institute of Electrical and Electronics Engineers, Inc.

M. S. Narasimhan

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IIT Madras

A correction to the available formula for the GTD near-field patterns of conical horns

IEEE Transactions on Antennas and Propagation

A novel technique for the analysis of the principal plane near-field patterns of conical and corrugated conical horns excited in the dominant mode based on the uniform geometrical theory of diffraction (UGTD) [1], [2] is presented. Numerical computations of the near-field amplitude patterns of a few typical conical and corrugated conical horns based on the GTD technique detailed here correlate well with the measured patterns, justifying the validity of the analysis presented. Copyright © 1979 by The Institute of Electrical and Electronics Engineers, Inc.

GTD Analysis of the Near-Field Patterns of Conical and Corrugated Conical Horns

An analytically simple and sufficiently accurate solution for the eigenvalues of a class of spherical wave functions is presented. The class of spherical wave functions considered are modes in conical and quasipyramidal waveguides with perfectly conducting walls and hybrid modes in corrugated conical and quasipyramidal horns with an impedance boundary. The indicated solution has been first used to obtain in closed form eigenvalues of the class of spherical wave functions considered which are subsequently used as the starting values for evaluating the exact eigenvalues with a simple digital-computer based iterative algorithm. The digital-computer evaluation of the eigenvalues has been found to be very fast, since the starting values are close to the exact solution, irrespective of the flare angle of the radial waveguides considered. Further, some mathematical insight has been provided in order to explain why the asymptotic solution, which appears to be valid only for small flare angles, yields eigenvalues close to the exact one even for wide flare angle(s) of the radial waveguides. © 1973, IEEE. All rights reserved.

Journal	IEEE Transactions on Antennas and Propagation
ISSN	0018926X
Open Access	No