In this communication, a novel compact spanner shaped ultra‐wideband (UWB) antenna is designed for multiple input multiple output (MIMO) system applications. The proposed structure of size 24 × 32 mm² (0.24λ₀ × 0.32λ₀, λ₀ is calculated at lower band frequency) is designed and fabricated on widely available FR4 dielectric material with a dielectric constant of 4.4 and loss tangent of 0.02. The proposed structure comprises two spanner shaped antennas, a defected T‐shaped stub and a pair of small vertical strips. The defected T‐shaped stub and vertical strips are used for getting a complete UWB bandwidth and good isolation between two elements. It is performing from 3.0 to 11.0 GHz with isolation more than 20 dB in most of the operating region. The parametric studies have been done for the required parameters and figured out the surface current distribution at different resonant frequencies within the working region. The MIMO antenna diversity performance is confirmed with low values of envelope correlation coefficient (ECC < 0.005), channel capacity losses (CCL < 0.04 bits/s/Hz), acceptable mean effective gain (MEG ≤ −3 dB, MEG ratio = 0 dB), and total active reflection coefficient (TARC ≤ −10 dB) values. The peak gain values are varying from 1.5 to 6.0 dBi, and the radiation efficiency values are above 83% for the entire operating region. The simulated and measured values are well matched.

中文翻译：

---

一种用于MIMO系统的新型紧凑型扳手形超宽带天线的设计与分析

在这种通信中，为多输入多输出（MIMO）系统应用设计了一种新颖的紧凑型扳手形超宽带（UWB）天线。大小的所提出的结构24×32毫米²（0.24λ ₀ ×0.32λ ₀，λ ₀是在较低的频带频率下计算得到的），并在介电常数为4.4，损耗角正切为0.02的广泛使用的FR4介电材料上进行设计和制造。提议的结构包括两个扳手形天线，一个有缺陷的T形短截线和一对小的垂直条。有缺陷的T形短截线和垂直条用于获得完整的UWB带宽和两个元素之间的良好隔离。它的工作频率为3.0至11.0 GHz，在大多数工作区域中的隔离度超过20 dB。已经对所需参数进行了参数研究，并找出了工作区域内不同谐振频率下的表面电流分布。MIMO天线分集性能可以通过较低的包络相关系数（ECC <0.005）得到确认，信道容量损耗（CCL <0.04 bits / s / Hz），可接受的平均有效增益（MEG≤-3 dB，MEG比= 0 dB）和总有效反射系数（TARC≤-10 dB）值。峰值增益值在1.5到6.0 dBi之间变化，并且整个工作区域的辐射效率值都超过83％。模拟值和测量值匹配良好。