A multistate high gain antenna based on metasurface

A multi-state high gain antenna based on metasurface is proposed. The antenna is composed of two stacking layers and a ground plane. The metasurface is constituted by two layers with the same size. And both of the two layers contain a copper patch array which is formed by 4 × 4 square copper cells uniformly distributed along x and y directions. The metasurface antenna is excited by the aperture coupled structure. The structure is consists of an anomaly microstrip line and a narrow slot etched in the ground plane. Genetic algorithm (GA) is adopted to optimize all the parameters and obtain the best performance of the metasurface antenna. By appropriately choosing the dimensions of the antenna, the proposed antenna can be achieved with the impedance bandwidth (RL≥10 dB) of about 340 MHz (7.8% at 4.36 GHz), 180 MHz (3.6% at 5.02 GHz), and 2800 MHz (41.1% at 6.81 GHz). The peak gain of the proposed antenna is 10.1dBi, 6.9 dBi, and 10.5dBi at 4.26 GHz, 5 GHz, and 7 GHz. In addition, the proposed metasurface antenna can work in multistate, which makes it an excellent candidate for practical applications.