Metamaterial integrated high directive antenna design for 5.8 GHz ISM band applications

In this thesis, low profile, high directive planar square and circular antennas were designed for 5.8 GHz ISM band applications. In the design of the antennas, GA/MoM optimization approach based on Moments Method (MoM) integrated with Genetic Algorithm (GA) was used, which is a fully automated design method. In the next step, a double negative index metamaterial unit cell with six different geometries were designed to be integrated into the structure of the antennas obtained as a result of the optimization process. Then, the rings forming the six metamaterial unit cells designed were rotated at a certain angle on their own axis and the radiation characteristics of the metamaterial unit cells were analyzed. Among these designed unit cells, a metamaterial unit cell that works in harmony with the antennas obtained as a result of optimization was selected. At the last step, the array structures were created with the selected metamaterial unit cell, and their simulations were made using the full-wave simulator HFSS electromagnetic simulation program by sequentially integrating the square and circular antennas obtained as a result of optimization. According to the simulation results, it was determined that the input reflection coefficient was below -10 dB, had high aperture efficiency, and high directive property in the ISM band where the antennas operating. In addition, it was observed that the far-field radiation properties of both proposed antennas integrated into the metamaterial were stable in the working band. Performance results for both proposed antennas that have been integrated into the metamaterial were showed and interpreted with graphs and tables. Keywords: Antennas, Metamaterial, Genetic Algorithm, Optimization