The design of a compact, wideband flexible monopole antenna printed on a flexible Kapton polyimide substrate is presented. The proposed antenna consists of two rhombic elements embedded within a square plane as the radiating element. The wide bandwidth is aimed at alleviating potential performance degradations due to its application in an on-body environment. The proposed antenna is designed using two main methods: the method of moments with adaptive cross approximation, and the characteristic mode analysis. The antenna operates from 2.038 to 3.745 GHz, indicating a bandwidth of 1.707 GHz (59.03%). Two dominant resonant frequencies are observed at 2.45 and 3.42 GHz, with realized gain of 3 and 5 dBi, and radiation efficiency of 90% and 83%, respectively. Besides that, the genetic algorithm and particle swarm optimization techniques are used to optimize the antenna and its performance validated via measurements. Besides, in free space, its on-body performance when placed in proximity of a human body phantom is evaluated. Finally, specific absorption rate assessment is performed to ensure the safety of the proposed antenna when operating on human. Results indicate the antenna's suitability for wearable applications to support different wireless standards.

中文翻译：

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使用 CMA 为 WBAN/WLAN 和 5G 应用设计紧凑、宽带和灵活的菱形天线

介绍了印刷在柔性 Kapton 聚酰亚胺基板上的紧凑型宽带柔性单极天线的设计。建议的天线由嵌入方形平面内的两个菱形元件组成，作为辐射元件。宽带宽旨在减轻由于其在身体环境中的应用而导致的潜在性能下降。所提出的天线设计使用两种主要方法：具有自适应交叉逼近的矩法和特征模式分析。天线的工作频率为 2.038 至 3.745 GHz，表明带宽为 1.707 GHz (59.03%)。在 2.45 和 3.42 GHz 处观察到两个主要谐振频率，实现增益分别为 3 和 5 dBi，辐射效率分别为 90% 和 83%。除此之外，遗传算法和粒子群优化技术用于优化天线及其通过测量验证的性能。此外，在自由空间中，评估其放置在人体模型附近时的在体性能。最后，进行特定的吸收率评估，以确保所提出的天线在人体上操作时的安全性。结果表明天线适用于可穿戴应用以支持不同的无线标准。