Acta Electronica Malaysia (AEM)

The 5G cellular network aims to address bandwidth needs due to the large number of subscribers worldwide. However, higher-bandwidth antennas are needed to integrate into the design. Helical antennas offer design simplicity, gain, and wider bandwidth, but their radiation pattern narrows bandwidth as diameter and turn increase. This paper aims to develop and evaluate the performance of helical antennas at different dimensions and turns for 4G and 5G network frequency applications. The study used MATLAB 2021a to design and simulate helical antennas with various turns. Parameters like width, spacing, and radius were calculated using an online helical antenna calculator at seven frequencies corresponding to 4G and 5G cellular networks. Major antenna properties, which include gain, directivity, bandwidth, efficiency, voltage standing wave ratio, return loss, front-to-back ratio, full null beam width, half power beam width, back lobe, main lobe, and side lobe, were evaluated. The study demonstrates that all simulated helical antennas show a continuous increase in gain with an increase in frequency. Directivity increases at lower frequencies but converges at higher 5G frequencies. The bandwidth also increases with frequency, making all helical turns suitable for 4G and 5G bandwidth, especially at higher frequencies. Efficiency also increases with frequency, with 2 and 4-turn helical antennas showing better performance at optimal frequencies. The 3-turn helical antenna meets the best VSWR and return loss standards, but its VSWR and return loss converge as frequency increases. The front-to-back ratio indicates that all helical antennas are more directional at higher frequencies. The back lobe decreases with frequency, while the main and side lobes are more pronounced at lower frequencies but converge at higher frequencies. Helical antennas with all realised turns show good characteristics with little tradeoff and are suitable for 5G bandwidth use at higher frequencies, and 2-turns offer potential for compact, miniaturised mobile device antenna applications.