2-bit programmable metasurface and antenna applications

Metamaterials are artificial materials produced in laboratory environment. Metasurfaces, also known as planar metamaterials, have found their place in important applications today due to their high level of unusual electromagnetic properties, low profile structures and ease of production. The functionality and electromagnetic properties of the metasurface can be changed or rearranged by manipulating the structure and dimensions. In this thesis, it is aimed to control the radiation direction of a monopole antenna and to improve the antenna gain and directionality. A microwave simulation program was used for design and simulations purposes. Two different unit cells are designed, and each unit cell contains two patches as resonators. One of the patches on the unit cells is circular and the other is rod-shaped. The antenna parameters can be adjusted by controlling the connection of these patches, which act as resonators, to the metal plate on the back surface of the FR4 material through vias. It is named "1" if there is contact between the resonator and metal plate, and "0" otherwise. In the study, metasurfaces are also produced and measurements are carried out using PNA-L N5234A Network Analyzer device. Simulation and measurement results have showed that the antenna parameters can be controlled. On the other hand, the measurement results are compared with both the simulation results and the literature results and it is seen that the results are in agreement.