Suresh Ankireddy Chandra, Reddy Thatiparthi Sreenivasulu, Madhav Boddapati Taraka Phani, Alshathri Samah, El-Shafai Walid, Das Sudipta, Sorathiya Vishal
Department of Electronics and Communication Engineering, Sri Venkateswara University College of Engineering, SV University, Tirupathi 517502, Andhra Pradesh, India.
Antennas and Liquid Crystals Research Center, Department of Electronics and Communication Engineering, Koneru Lakshmaiah Education Foundation, Guntur 522302, Andhra Pradesh, India.
Micromachines (Basel). 2023 Mar 7;14(3):612. doi: 10.3390/mi14030612.
In this article, a 4 × 4 miniaturized UWB-MIMO antenna with reduced isolation is designed and analyzed using a unique methodology known as characteristic mode analysis. To minimize the antenna's physical size and to improve the isolation, an arrangement of four symmetrical radiating elements is positioned orthogonally. The antenna dimension is 40 mm × 40 mm (0.42λ× 0.42λ) (λ is the wavelength at first lower frequency), which is printed on FR-4 material with a width of 1.6 mm and εr = 4.3. A square-shaped defected ground framework was placed on the ground to improve the isolation. Etching square-shaped slots on the ground plane achieved the return losses S < -10 dB and isolation 26 dB in the entire operating band 3.2 GHz-12.44 GHz (UWB (3.1-10.6 GHz) and X-band (8 GHz-12 GHz) spectrum and achieved good isolation bandwidth of 118.15%. The outcomes of estimated and observed values are examined for MIMO inclusion factors such as DG, ECC, CCL, and MEG. The antenna's performances, including radiation efficiency and gain, are remarkable for this antenna design. The designed antenna is successfully tested in a cutting-edge laboratory. The measured outcomes are quite similar to the modeled outcomes. This antenna is ideal for WLAN and Wi-Max applications.
在本文中，使用一种称为特征模式分析的独特方法设计并分析了一种具有降低隔离度的4×4小型化超宽带多输入多输出（UWB-MIMO）天线。为了最小化天线的物理尺寸并提高隔离度，四个对称辐射元件正交排列。天线尺寸为40 mm×40 mm（0.42λ×0.42λ）（λ是第一个较低频率处的波长），印刷在厚度为1.6 mm、相对介电常数εr = 4.3的FR-4材料上。在接地面上放置了一个方形缺陷接地框架以改善隔离度。通过在接地面上蚀刻方形缝隙，在整个3.2 GHz - 12.44 GHz工作频段（超宽带（3.1 - 10.6 GHz）和X波段（8 GHz - 12 GHz）频谱）实现了回波损耗S < -10 dB以及26 dB的隔离度，并获得了118.15%的良好隔离带宽。针对多输入多输出包含因子，如方向增益（DG）、互耦系数（ECC）、相关系数（CCL）和平均有效增益（MEG），对估计值和观测值的结果进行了检验。该天线设计的辐射效率和增益等性能表现出色。所设计的天线在一个先进实验室中成功进行了测试。测量结果与建模结果非常相似。该天线非常适合无线局域网（WLAN）和全球微波接入互操作性（Wi-Max）应用。
