A flexible folded-shorted patch (FSP) antenna with dual-band functionality for wearable applications is presented. The proposed antenna is operational at 400 MHz and 2.4 GHz and can be considered compact for the lower operational frequency band ( $0.13\lambda _{o} \times 0.13\lambda _{o} \times 0.02\lambda _{o}$ ). Flexible polydimethylsiloxane (PDMS) is used as the substrate due to its relatively low-cost as well as its robustness for wearable applications. A comparison of the fields radiated by the FSP, in terms of the $TM_{010}$ and $TM_{001}$ modes are also presented considering the cavity model which is actually related to the two noted operating bands. Equations needed to calculate the beam pattern and directivity for these modes are also derived and their results are compared to commercial full-wave simulations and measurements of a wearable PDMS prototype. An analysis was also performed to characterize the relevant dimensions that are important for independently controlling or tuning the resonant frequencies for these two radiating modes. The proposed antenna can be suitable for robust wearable applications such as military search and rescue operations, emergency response team units, and medical services.

中文翻译：

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稳健可穿戴应用的双频折叠式贴片天线的分析和设计

提出了一种适用于可穿戴应用的具有双频功能的柔性折叠短路贴片（FSP）天线。拟议的天线可在400 MHz和2.4 GHz的频率下工作，对于较低的工作频段，该天线可以认为是紧凑的（ $ 0.13 \ lambda _ {o} \ times 0.13 \ lambda _ {o} \ times 0.02 \ lambda _ {o} $ ）。柔性聚二甲基硅氧烷（PDMS）由于其相对较低的成本以及对可穿戴应用的坚固性而被用作基材。FSP辐射场的比较，就 $ TM_ {010} $ 和 $ TM_ {001} $ 还考虑了实际上与两个所述工作频带有关的空腔模型，给出了两种模式。还推导了计算这些模式的波束方向图和方向性所需的公式，并将其结果与可穿戴PDMS原型的商业全波仿真和测量结果进行了比较。还进行了分析以表征相关尺寸，这些尺寸对于独立控制或调整这两种辐射模式的共振频率很重要。拟议中的天线可能适用于坚固耐用的可穿戴应用，例如军事搜索和救援行动，应急小组和医疗服务。