Hybrid parasitic surface method for mutual coupling reduction in circular polarized microstrip antennas with WOA Optimization

Abstract Multiple-input multiple-output (MIMO) technologies play an indispensable role in modern telecommunications, prominently featured in systems like Wireless Local Area Networks (WLAN) and Long-Term Evolution (LTE). Massive MIMO (M-MIMO) systems are seen as pivotal to the infrastructure of 5 G communication networks. It is expected that M-MIMO technology will transform future wireless communication frameworks and cellular networks. A major challenge in this area is the mitigation of mutual coupling between element uses for antennas. This paper presents a novel strategy for reducing mutual coupling in large antenna arrays, which involves the use of the Whale Optimization Algorithm (WOA) to optimize design parameters. A newly engineered plate, consisting of multiple small components that generate electrical interference, is positioned in front of the antenna array. By partially diffracting incoming waves, this plate can be adjusted to diminish unwanted coupled signals. The resonant frequency of the array element is established at 2.45 GHz, aligning with mainstream 5 G mobile network spectrum allocations featuring circular polarization. New elements have been incorporated to improve isolation between adjacent antenna elements, resulting in more than a 15 dB reduction in mutual coupling. The envelope correlation for a 2×2 array is provided to substantiate the proposed method. Measured efficiencies of 72.9% and envelope correlation coefficients (ECCs) below 0.31 for the 2×2 MIMO system have been achieved. It is suggested that MIMO systems can enhance channel capacity for compact 5 G mobile antennas, yielding improved isolation and diversity performance.