One-dimensional electromagnetic bandgap for directivity enhancement of waveguide antennas

A deformed 1D electromagnetic bandgap (EBG) is constructed by finite dielectric discs staked in front of the antenna. The dielectric discs of quarter-dielectric-wavelength thickness separated by a quarter wavelength and placed a half wavelength from the flanged waveguide aperture are studied. Such an arrangement enhances the antenna directivity. The effect of different parameters on the antenna directivity is investigated when one finite disc is considered. Two dielectric discs are also studied and show that the directivity increases further as the number of discs increases. The analysis is carried out numerically using a method of moments (MoM) code for bodies of revolution. Two antennas are build to verify the effect of the dielectric disc on the antenna directivity. It is found that this concept is valid regardless of the aperture shape. © 2005 Wiley Periodicals, Inc. Microwave Opt Technol Lett 47: 430–434, 2005; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.21192