Compact Microstrip Patch Antenna with Rectangular DGS for Wi-Fi Applications

Over the past several years, antenna miniaturization has become a key focus of research for engineers specializing in antenna design. In this paper, an inset-fed microstrip patch antenna incorporating a rectangular slot etched in the ground plane is presented. The proposed design utilizes the Defected Ground Structure (DGS) concept to achieve antenna miniaturization. A parametric analysis is conducted to determine the optimal length, width, and placement of the rectangular slot on the ground plane. The antenna is constructed using an FR-4 substrate with dimensions of 0.1816λ0 × 0.216λ0 × 0.0128λ0, where λ0 denotes the free-space wavelength corresponding to a frequency of 2.4 GHz. Simulation outcomes indicate that the proposed antenna achieves an impedance bandwidth of 4.77% (5.12 GHz to 5.37 GHz) when no DGS is used, whereas incorporating a rectangular DGS results in an impedance bandwidth of 5.34% (2.37 GHz to 2.5 GHz). Using the proposed method, a size reduction of up to 67.05% is achieved compared to the conventional antenna. The antennas were simulated and optimized using CST Microwave Studio, and the fabricated prototypes were evaluated with a Rohde & Schwarz ZVL13 VNA. Both simulation and experimental results confirm that the proposed antenna operates within the 2.4 GHz Wi-Fi band.