In this paper, impedance matching enhancement of a grounded wearable low-profile loop antenna is investigated using a high-impedance surface (HIS) structure. The wearable loop antenna along with the HIS structure is maintained low-profile, making it a suitable candidate for healthcare applications. The paper starts with investigating, both numerically and experimentally, the effects of several textile parameters on the performance of the wearable loop antenna. The application of impedance enhancement of wearable grounded loop antenna with HIS structure is then demonstrated. Numerical full-wave simulations are presented and validated with measured results. Unlike the grounded wearable loop antenna alone with its degraded performance, the wearable loop antenna with HIS structure showed better matching performance improvement at the 2.45 GHz-band. The computed overall far-field properties of the wearable loop antenna with HIS structure shows good performance, with a maximum gain of 6.19 dBi. The effects of bending the wearable loop antenna structure with and without HIS structure as well as when in close proximity to a modeled human arm are also investigated, where good performance was achieved for the case of the wearable antenna with the HIS structure.

中文翻译：

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使用高阻抗表面（HIS）增强医疗接地的纺织品接地环形天线的阻抗。

在本文中，使用高阻抗表面（HIS）结构研究了接地可穿戴式薄型环形天线的阻抗匹配增强。可穿戴环形天线以及HIS结构保持低调，使其非常适合医疗保健应用。本文首先通过数值和实验研究几种纺织品参数对可穿戴环形天线性能的影响。然后说明了具有HIS结构的可穿戴接地环形天线的阻抗增强的应用。提出了全波数值模拟并通过测量结果进行了验证。与单独的接地可穿戴式环形天线相比，其性能下降，而具有HIS结构的可穿戴式环形天线在2.45 GHz频段上显示出更好的匹配性能。具有HIS结构的可穿戴环形天线的计算出的总体远场特性显示出良好的性能，最大增益为6.19 dBi。还研究了弯曲带有或不带有HIS结构的可穿戴环形天线结构以及紧靠建模的人体手臂时的弯曲效果，对于带有HIS结构的可穿戴天线而言，可以获得良好的性能。