Metamaterial-inspired antenna designs for IoT/5g applications

The convergence of the Internet of Things (IoT) and Fifth Generation (5G) networks has increased the need for efficient antenna designs in compact devices and dense network environments. This thesis presents an in-depth investigation of frequency reconfigurable metamaterial-based antennas, focusing particularly on applications below 6 GHz. The main purpose in this study is to develop novel antenna designs that utilize the properties of metamaterial structures, achieving compactness and frequency reconfigurability. Through an extensive literature review, the thesis examines the effects of metamaterial-based antennas and Split Ring Resonator (SRR) structures on antenna performance within the IoT and 5G contexts. The study proposes and investigates novel designs for frequency reconfigurable antennas. The designs incorporate diverse resonators, including SRRs, and employ different switching mechanisms such as PIN diodes, SPDT switches, and copper path alterations to modify the electrical length of the antennas. Significant antenna parameters such as Return Loss, Radiation Pattern and Radiation Efficiency are analyzed in the sub-6 GHz range. Prototypes of the proposed frequency reconfigurable antennas are also tested experimentally. The simulation and experimental results validate the efficacy of the proposed designs, demonstrating significant size reduction, high efficiency, and dynamic frequency adaptability. Thus, this study addresses the important gaps in wireless communication systems in terms of frequency reconfiguration, compactness and radiation efficiency.