Dual-Band Two-Sided Beam Generation Utilizing an EBG-Based Periodically Modulated Metasurface

We propose a periodically modulated metasurface (MTS) capable of producing two-sided electromagnetic (EM) beams with frequency-controlled beam reconfiguration. The beam-forming functionality is realized through the leaky-wave (LW) conditions of the periodic structure, and the beam reconfiguration at quadrature azimuth angle is triggered by switching between the two operating frequencies. The MTS is formed using a periodic homogeneous array of split ring resonators (SRRs) with anisotropic characteristics. The EM bandgap (EBG) properties and LW conditions of the individual SRRs are combined to produce both beam-forming and beam-reconfiguration functionalities. The subwavelength SRR unit cells are designed such that they satisfy LW theory at 1.8 GHz to form a two-sided beam along azimuth angles 0° and 180° and create a complete EBG at 2.6 GHz to form a two-sided beam along angles 90° and 270° at 2.6 GHz. Both the TE and TM mode responses of the individual SRRs are taken into consideration during the design process. The MTS structure is synthesized and evaluated using full-wave EM simulator and is validated with the experimental results.