In this article, a dual-port aperture-coupled circular fractal antenna array is designed, developed and tested for its usage in 4G, WLAN, radar, satellite and ISS communication systems, covering C-band, X-band and Ku-band of frequencies. The proposed array is designed on two FR-4 substrates (with overall dimensions of 34 × 68.7 × 3.245 mm3) where the upper and lower substrate consists of circular fractal radiators (2nd order of iteration) and a feed network respectively. The aperture slots in the ground are transformed into complementary rectangular spiral slots with a tree-shaped DGS, to achieve the desired operational band (4.6–16.8 GHz) with improved matching performance. It provides a maximum gain of 4.57 dB (at 6.6 GHz) and high port-to-port isolation (S21 ≤ −19 dB) performance. The implementation of the proposed array in MIMO systems is validated by various diversity parameters like low ECC, high DG, high MEG, low CCL and stable TARC attributes. An acceptable agreement is achieved between the simulated and experimental results.

中文翻译：

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用于 4G/WLAN/雷达/卫星/国际空间站 (ISS) 通信系统的具有互补矩形螺旋缺陷接地结构 (DGS) 的 UWB 孔径耦合圆形分形 MIMO 天线

在本文中，设计、开发和测试了双端口孔径耦合圆形分形天线阵列在 4G、WLAN、雷达、卫星和国际空间站通信系统中的使用，覆盖 C 波段、X 波段和 Ku 波段的频率。所提出的阵列设计在两个 FR-4 基板（总尺寸为 34 × 68.7 × 3.245 mm3）上，其中上下基板分别由圆形分形辐射器（二阶迭代）和馈电网络组成。地面中的孔径槽被转换为带有树形 DGS 的互补矩形螺旋槽，以实现所需的工作频段（4.6-16.8 GHz）并提高匹配性能。它提供 4.57 dB（在 6.6 GHz 时）的最大增益和高端口到端口隔离 (S21 ≤ −19 dB) 性能。所提出的阵列在 MIMO 系统中的实施得到了各种分集参数的验证，如低 ECC、高 DG、高 MEG、低 CCL 和稳定的 TARC 属性。在模拟和实验结果之间实现了可接受的一致性。