A dual-band stacked antenna integrated with a rescue helmet is proposed for WLAN applications. The cross slot aperture feeding technique enables the antenna to support dual-band operation at 2.4 and 5 GHz. On the ground plane, two slots are formed, perpendicular to each other and of different lengths. Four dielectric layers of different permittivity are stacked over this cross slot to attain the desired frequency bands. Under free space condition, the radiator yields 7% (2.31–2.48 GHz), 15.87% (5.12–6 GHz) 10 dB return loss bandwidth (BW). The use of low loss dielectric layers on the slots also provides a high antenna efficiency and moderate gain at both frequency bands. The small dimension of antenna encourages its use as a wearable helmet antenna. Antenna performances are observed under wearable condition. For assessing human exposure to RF electromagnetic fields, SAR evaluations are conducted at both 2.4 and 5 GHz WLAN bands.

中文翻译：

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集成到救援头盔中的高效双频段堆叠天线用于室内通信

提出了一种用于 WLAN 应用的与救援头盔集成的双频段堆叠天线。交叉缝隙孔径馈电技术使天线能够支持 2.4 和 5 GHz 的双频操作。在接地平面上，形成两个相互垂直且长度不同的槽。四个不同介电常数的介电层堆叠在这个交叉槽上以获得所需的频带。在自由空间条件下，辐射器产生 7% (2.31–2.48 GHz)、15.87% (5.12–6 GHz) 10 dB 回波损耗带宽 (BW)。在狭缝上使用低损耗介电层还提供了高天线效率和两个频段的中等增益。天线的小尺寸鼓励其用作可穿戴头盔天线。在可穿戴条件下观察天线性能。