Development of antenna array using Defected Ground Structure

This paper presents preliminary structure of a 4×4 frequency reconfigurable microstrip array antenna using Defected Ground Structures (DGS) with aperture coupled feed line. Two resonant frequencies obtained from two different sizes of dumbbell structures etched on the ground plane are 7.5 GHz and 8.85 GHz respectively. The reconfigurability features of the antenna are based on the transition modes of switch on the feed line. If the switching is in “OPEN” mode the antenna resonates at 7.5 GHz, while in “SHORT” the antenna resonates at 8.85GHz. Switching modes for the preliminary prototype are presented in open and short condition of the feeding line. The reconfigurable array antenna has been simulated using Computer Simulation Technology (CST). Results between simulation and measurement provide good agreement of the designed antenna. This new approach offers simple design and expandable array element to improve the antenna directivity for future outdoor wireless applications.