A Novel Supercell-Based Dielectric Grating Dual-Beam Leaky-Wave Antenna for 60-GHz Applications

This communication proposes a novel dual-beam dielectric grating antenna based on the supercell (SC) concept. Through the theoretical analysis of the effective phase constants of the SC, it is found that two space harmonic modes (m=-1 and m=-2) can be simultaneously excited (above the air line) within a certain frequency range. This phenomenon leads to the generation of two radiation beams in the far-field region. At the frequency where the phase constants satisfy β_-1=-β_-2, the two beams are in symmetric directions with respect to the axis that is perpendicular to the azimuth plane. Different from the conventional periodic structures that the m=-2 mode lacks well control, the proposed antenna can manipulate both modes and obtain equal performance for the two radiation beams. In this communication, the symmetric beam case is investigated. The detailed design principle is presented. In addition, the frequency-based beam steering characteristic that the two beams scan in the same clockwise or anticlockwise direction is discussed as well. The proposed antenna operates in 60-GHz band and it can be a good candidate for the WiGig application.