Summary
International Symposium on Antennas and Propagation
2006
Session Number:2POS
Session:
Number:2POS-14
Grating-Lobe Suppression in a Linear Array of a Hollow Waveguide Transverse Slots by a Layer of Parasitic Dipole-Quartets
Mitsuru Kirita, Jiro Hirokawa, Makoto Ando,
pp.1-4
Publication Date:2006/11/2
Online ISSN:2188-5079
Summary:
A linear array of transverse slot on the broad-wall of a hollow waveguide suffers the grating lobe problem because the element spacing is longer than the free-space wavelength. Addition of a parasitic dipole pair just above each slot was proposed to suppress the grating lobes. However the calculation of the three-dimensional radiation pattern of the slot and the dipole pair reveals that they have unwanted radiation to oblique directions. In order to solve this problem, a parasitic dipole quartet is introduced for each slot in this paper. This configuration can suppress the unwanted radiation to -13dB on φ= 90° and -l5dB on φ= 50°in the experiment.