Gain improvement for rectangular horn antenna by using curved-woodpile metamaterial

This paper proposes the new technique of the metamaterial on the structure of the curved-woodpile Electromagnetic Band Gap (EBG) for gain improvement of a conventional rectangular horn antenna without its construction enlargement. The curved-woodpile EBG, which is the 3D volumetric structure, has been utilized to enhance the gain instead by transferring the electromagnetic fields from aperture of a horn through this EBG. This paper also presents the design procedures of a dielectric which is inserted in layers of the curved-woodpile EBG for reducing the distance between a horn and EBG. The proposed technique has the advantages of low profile, low cost for fabrication and light weight. From the results by using the simulation software, the gain at the operating frequency of 10 GHz is 24.17 dB, suitable for application for X-band radar and I-band beyond following the IEEE and the ITU, respectively, that higher than the gain of the basic rectangular horn antenna around 7 dB with adding only one appropriated metamaterial structure.