Amplitude and phase-shaping effects in beamwaveguides

Author

Rengarajan, Sembiam R. ; Galindo-israel, Victor ; Imbriale, William A.

Author_Institution

Dept. of Electr. & Comput. Eng., California State Univ., Northridge, CA, USA

Volume

39

Issue

5

fYear

1991

fDate

5/1/1991 12:00:00 AM

Firstpage

687

Lastpage

690

Abstract

Results are presented of an investigation on improvements in a geometrical optics design of a beam-waveguide antenna for operation at multiple frequency bands. Improvements might be possible by changing the design of the lower-frequency input pattern to the beam waveguide. The effects of amplitude and phase shaping the input pattern have been studied with an aperture diffraction model. Accurate vector near-field computations were made rapidly with a spherical wave expansion of the input and scattered fields. Numerical results indicate that for aperture sizes of less than 30 wavelengths, there is insufficient control on defocusing due to amplitude and phase shaping. Design tradeoffs on spillover loss and defocusing are possible by changing the amplitude and phase distribution of the input wavefront for larger size apertures

Keywords

antenna feeders; geometrical optics; reflector antennas; waveguide antennas; amplitude effects; aperture diffraction model; beam-waveguide antenna; defocusing; geometrical optics design; multiple frequency bands; numerical results; phase-shaping effects; reflector antennas; spherical wave expansion; spillover loss; vector near-field; Apertures; Frequency; Geometrical optics; Multifrequency antennas; Optical design; Optical diffraction; Optical scattering; Optical waveguides; Shape control; Size control;

fLanguage

English

Journal_Title

Antennas and Propagation, IEEE Transactions on

Publisher

ieee

ISSN

0018-926X

Type

jour

DOI

10.1109/8.81504

Filename

81504