2.4 GHz超高隔离度双端口圆形贴片天线

摘要

2.4 GHz工业、科学与医疗（ISM）频段中可靠的无线通信，日益依赖能够在多输入多输出（MIMO）配置下提供高端口间隔离度的天线系统。本文提出一种圆形微带贴片天线，并将其扩展为面向2.4 GHz工作的双端口MIMO结构。该天线实现在低损耗基板上，并通过全波电磁仿真评估其阻抗匹配、辐射性能与MIMO分集指标。为提升阵列的端口间隔离度，本文在两个辐射单元之间引入了一种倒U形缺陷地结构（DGS）。优化后的设计在2.4 GHz附近取得优异的匹配以及约−78.7 dB的超高隔离度，同时在整个工作频段内保持稳定的增益与辐射方向图。上述结果表明，所提天线为物联网（IoT）及其他短距离无线通信系统中紧凑、高能效且稳健的2.4 GHz MIMO前端提供了一种简单而有效的解决方案。

Abstract

Reliable wireless communication in the 2.4 GHz industrial, scientific, and medical band increasingly relies on antenna systems that can provide high inter-port isolation in multiple-input multiple-output (MIMO) configurations. This paper presents a circular microstrip patch antenna and its extension to a dual-port MIMO configuration designed for 2.4 GHz operation. The antenna is implemented on a low-loss substrate and evaluated using full-wave electromagnetic simulations to assess impedance matching, radiation performance, and MIMO diversity metrics. To enhance inter-port isolation in the array, an inverted U-shaped defected ground structure (DGS) is introduced between the two radiating elements. The optimized design achieves excellent matching around 2.4 GHz and ultra-high isolation of approximately -78.7 dB, while maintaining stable gain and radiation patterns across the operating band. These results indicate that the proposed antenna offers a simple and effective solution for compact, energy-efficient, and robust 2.4 GHz MIMO front ends in internet of things (IoT) and other short-range wireless communication systems.