A Novel Monopole Antenna for Wideband(Ultra) Wireless Applications with Defected Ground Structure (DGS)

For Microwave C (4-8 GHz) and X (8-14 GHz) band applications, a wideband monopole antenna with a defective ground structure has been proposed in this paper. With a substrate thickness of 1.6 mm and a low-loss dielectric substrate of Glass Epoxy (FR4) with dielectric constant (ε
r
) of 4.4, a standard printed monopole antenna is designed and simulated with an operating range frequency of center 4.8 GHz. The three square-shaped slots in the ground plane are etched to increase the band width of this monopole antenna. Thorough optimization is used to determine the DGS (Defect Ground Structure) slots. Results from the simulation using the HFSS (High Frequency Structure Simulator) show good radiation pattern and a wide bandwidth with a peak gain of more than 4.8 dBi. In proposed design, a 5 mm semicircle on the patch with edges provides better ultra wideband behavior for the antenna for X band.