Design of mm-Wave RLSAs with Lossy Waveguides by Slot Coupling Control Techniques

Tung NGUYEN  Jiro HIROKAWA  Makoto ANDO  Manuel SIERRA CASTAÑER  

Publication
IEICE TRANSACTIONS on Communications   Vol.E98-B   No.9   pp.1865-1872
Publication Date: 2015/09/01
Online ISSN: 1745-1345
DOI: 10.1587/transcom.E98.B.1865
Type of Manuscript: PAPER
Category: Antennas and Propagation
Keyword: 
lossy waveguides,  radial line slot antenna,  millimeter wave,  coupling factors,  

Full Text: FreePDF(2.4MB)


Summary: 
This paper discusses how to design a Radial Line Slot Antenna (RLSA) whose waveguide is filled with high loss dielectric materials. We introduce a new design for the aperture slot coupling synthesis to restrain the dielectric losses and improve the antenna gain. Based on a newly defined slot coupling, a number of RLSAs with different sizes and loss factors are analyzed and their performances are predicted. Theoretical calculations suggest that the gain is sensitive to the material losses in the radial lines. The gain enhancement by using the new coupling formula is notable for larger antenna size and higher loss factor of the dielectric material. Three prototype RLSAs are designed and fabricated at 60GHz following different slot coupling syntheses, and their measured performances consolidate our theory.