A Circular Patch Multiband Antenna with Defected Ground Structure for WLAN and WiMAX Networks: Design, Analysis, and Performance Evaluation

An application-specific circular patch multiband antenna with Defected Ground Structure (DGS) has been proposed for use in WLAN and WiMAX networks. Analyses and comparisons are made between the DGS and the performance of the circular patch antenna when it is used with the full ground. The circular patch antenna has a size of (47mm × 35mm) and a thickness of 1.5 mm. This paper presents the design process, parametric analysis, simulation results, and measurements for the patch antenna incorporating DGS configuration. The antenna operates at 2.4 GHz, 3.6 GHz, 5.2 GHz, 5.5 GHz, and 5.8 GHz, with a bandwidth of 3.6 GHz (2.31 GHz to 6.08 GHz). The antenna offers a peak return loss of -41.59 dB at 3.17 GHz and maintains a favourable return loss throughout its entire operating band. The proposed antenna exhibits a gain of 5.12 dB, along with a radiation efficiency of 96% and directivity of 2.35 dBi. The current distribution, impedance matching, and voltage standing wave ratio (VSWR) are all favourable in the operating bands. We have analysed the current distributions, and our demonstration indicates that they are satisfactory. The antenna is constructed using Rogers RT/Duroid 5880 substrate, which has a dielectric constant of 2.2. To simulate the proposed antenna, we employed Ansys Electronics 2023 R1, which is a frequency-domain finite element method (FEM) based simulation tool. The simulation results closely correspond with the measured radiation characteristics (in E and H planes, return loss etc.) of the circular patch DGS antenna design. The proposed antenna design is highly suitable for wireless communication applications, as it meets satisfactory criteria for various parameters, such as gain, bandwidth ratio, and efficiency. Additionally, it has a compact size, lightweight construction, and an uncomplicated design.