Optimizing a Star-Octagonal Microstrip Patch Antenna for 5G: Design and CST Simulation Approach

This research describes the design, simulation and analysis of a low-profile patch antenna specifically suited for 5G communication at a frequency of 3.5 GHz. The antenna utilizes a Rogers RT5880 fire-retardant substrate with a dielectric constant of 2.2 and dimensions of 60mm x 60mm. The radiating patch features a unique star-octagonal shape with a defected ground structure for optimized performance. A strip line feed is employed to excite the antenna. CST Microwave Studio, a software program for electromagnetic simulation, was used throughout the design, analysis and simulation process. The proposed patch antenna achieves a wide range of operability with a good return loss of -25 dB, a gain of 4.82 dBi, good directivity of 4.83 dBi, and a narrow bandwidth at 3.27 GHz. Key antenna parameters including S-parameters, gain, directivity and efficiency were analyzed, and the results are presented in a table for further reference.