High-Gain Low-Profile EBG Resonator Antenna Based on Quasi-Icosahedral Shapes

Studying the geometry of electromagnetic band gap (EBG) structures in 1 and 3 dimensions is useful for achieving effective directional radiation, high gain, and side-lobe attenuation of antennae. This paper presents an EBG antenna, whose radiating source is a rectangular notched patch, which can be used for applications around 20 GHz. Two conventional woodpile dielectric structures with a triangular lattice are presented in a comparative study to extract the best physical and electromagnetic performance in terms of directivity, bandwidth, and gain; these are the square and the cylindrical rods. These two structures’ electromagnetic and geometrical limits allow the design of a 3D EBG structure called an icosahedral structure. The proposed antenna is composed of different ceramic substrates (the Arlon AR 450, (h = 0.48 mm, ɛ_r = 4.5, El Tand = 0.0035) on which the radiating element is placed, the Rogers TMM 13i, (ɛ_r = 12.85, El Tand = 0.0019) for the 3D icosahedral structure; and the Taconic TLY-5A, (ɛ_r = 2.17, El Tand = 0.0009) for the 1D lateral walls). With a substrate-plated radiation source coupled with a 3D icosahedral structure and surrounded by a vertically mounted 1D structure, a directivity of 19 dBi was obtained with a realized gain of 17.7 dB and an optimal coupling (antenna–EBG material) at 19.8 GHz. These results are encouraging given the antenna size of 33.41 × 27.87 × 37.36 mm³.