Dhananjeyan R, Ramesh S, Kumar D Rajesh, Kumar Om Prakash
Department of Electronics and Communication Engineering, SRM Valliammai Engineering College, Chennai, India.
Department of Electronics and Communication Engineering, Vel Tech Rangarajan Dr. Sagunthala R&D Institute of Science and Technology, Chennai, Tamilnadu, India.
Sci Rep. 2025 May 29;15(1):18921. doi: 10.1038/s41598-025-03494-7.
This work introduces a compact and novel MIMO antenna system with close spacing and exceptional isolation, tailored for broadband usage across frequencies from 3.7 to 11 GHz. The antenna configuration consists of two octagonal radiators, each individually powered by a 50 Ω microstrip line. The use of a modified ground structure ensures a wideband frequency range. A key novelty of this design is the incorporation of a strategically placed stub (25.6875 × 0.5 mm) between the radiating sections, which significantly enhances inter-port isolation, achieving over 15 dB despite the minimal 3 mm port separation-an improvement over conventional MIMO antennas. This design enables high isolation without increasing antenna size, making it highly efficient for compact wireless systems. Performance evaluation, including fabrication and testing, demonstrates a strong alignment between simulation and experimental data. Metrics such as envelope correlation coefficient (ECC), diversity gain (DG), and channel capacity loss (CCL) were analyzed to assess MIMO efficiency. The proposed antenna is ideal for broadband wireless systems with a peak gain of 6.5 dBi and excellent resonance, offering superior isolation and compactness compared to existing designs.
这项工作介绍了一种紧凑且新颖的多输入多输出（MIMO）天线系统，该系统间距小且隔离度优异，专为3.7至11 GHz频段的宽带应用而设计。天线配置由两个八角形辐射器组成，每个辐射器由一条50 Ω微带线单独供电。采用改进的接地结构可确保宽带频率范围。该设计的一个关键新颖之处在于在辐射部分之间战略性地放置了一个短截线（25.6875×0.5 mm），这显著提高了端口间隔离度，尽管端口间距最小仅为3 mm，但仍实现了超过15 dB的隔离度——这比传统MIMO天线有了改进。这种设计能够在不增加天线尺寸的情况下实现高隔离度，使其对于紧凑型无线系统非常高效。包括制作和测试在内的性能评估表明，仿真数据与实验数据高度吻合。分析了诸如包络相关系数（ECC）、分集增益（DG）和信道容量损失（CCL）等指标来评估MIMO效率。所提出的天线对于宽带无线系统而言是理想之选，其峰值增益为6.5 dBi，谐振性能出色，与现有设计相比，具有卓越的隔离度和紧凑性。
