Multi-beam Antenna Based on Square Ring Slot and Metasurface

This paper proposes a multi-beam antenna based on square ring slot and metasurface. Steering the beam in the elevation plane is realized by placing metasurface above the radiating element. And the non-uniform characteristics of the metasurface helps to make the beam more concentrated. Also, the gain of the proposed antenna is improved by increasing the number of square ring slot. The results show that the antenna radiates four beams pointing at (theta, phi) = (30 degrees, 0 degrees), (30 degrees, 90 degrees), (30 degrees, 180 degrees), (30 degrees, 270 degrees). The -10 dB impedance bandwidth of the antenna is 3.94 similar to 5.50 GHz (1.56 GHz), and the gain of the antenna is 9.56 dBi.