DESIGN AND SIMULATION OF A MICROSTRIP ANTENNA FOR 28GHZ 5G WIRELESS COMMUNICATION WITH PERFORMANCE EVALUATION AT DIFFERENT SUBSTRATE HEIGHTS

This project presents the design and simulation of a microstrip antenna for 5G communications at 28GHz frequency. The study aim was to evaluate the effects of varying substrate thickness of microstrip antenna on the performance metrics. The microstrip antenna was designed in the CST Studio Suite 2024. Rogers RT/Duroid 5880 was chosen as the substrate material due to its low dielectric loss and high performance at millimeter-wave frequencies. Three antenna models were designed at substrate heights of 0.508mm for design I, 0.787mm for design II, and 1.575mm for design III. The Transmission Line Model (TLM) was used to calculate the patch and feedline dimensions before optimizing the designs. The performance of each design was evaluated based on key parameters such as return loss, bandwidth, VSWR, gain, radiation, efficiency, surface current, and polarization behavior. Furthermore, the performance results of the three designs were compared among themselves and with 13 similar research design results from literature. The results showed that design I has Return loss of –44.54 dB, Bandwidth of 1.017 GHz, Efficiency of 76.43%, VSWR of1.012, a Gain of 6.61 dBi, and a Directional radiation pattern with suppressed side lobes. Similarly, for design II, the results gave –47.59 dB, 3.39 GHz, 83.9%, 1.008, 5.43 dBi and Broad beam (95.2°) with side lobes at –4.5 dB for Return loss, Bandwidth, Efficiency, VSWR, Gain and radiation pattern respectively. For Design III, the values are –55.37 dB, 4.465 GHz, 73.9%, 1.003, 7.82 dBi and Narrow beam (33.8°) radiation pattern with high directivity of 9.13 dBi respectively. A comparative analysis of the Simulation results shows that design III achieved the best overall performance, obtaining the highest gain of 7.82dBi, the widest bandwidth of 4.465GHz, and a return loss of -56.211dB. Its only deficiency is the total efficiency of 73.9%; which is still within standard range of operation, but the high gain and wide bandwidth make it suitable for high-speed 5G applications. All the designs are good for various applications in 5G communication