对MIMO天线进行SAR评估,这些天线具有广泛可调节范围的功率分隔器
Yuhang Gu1, Jialin Huang1, Ruiya Shi1
1State Key Laboratory of Integrated Optoelectronics, JLU Region, College of Electronic Science and Engineering, International Center of Future Science, Jilin University, 2699 Qianjin Street, Changchun, 130012, China.
Scientific reports
|April 8, 2025
概括
本研究介绍了使用可调节功率分隔器的身体穿戴多天线系统的特定吸收率 (SAR). 结果显示,SAR取决于功率比和接近身体的距离,为低SAR可穿戴天线提供设计指南.
科学领域:
- 电磁学和计算生物学 电磁学和计算生物学
- 可穿戴技术和天线设计
- 无线电频率 (RF) 安全和剂量测量
背景情况:
- 对于多天线系统的特异吸收率 (SAR),特别是移动设备的特征,存在重大挑战.
- 带有动态机体区域网络 (BAN) 频道的活性组件的身体穿戴天线使多输入多输出 (MIMO) 系统的SAR合规性测试复杂化.
研究的目的:
- 介绍SAR的第一个表征,用于与可调节微波功率分隔器集成的身穿多天线系统.
- 调查MIMO-SAR对重量函数,功率比,交叉极化功率比 (XPR) 和天线倾斜角度的依赖.
- 为集成可穿戴天线和活性微波电路提供设计指南,降低SAR.
主要方法:
- 用多层人体模型进行剂量测量分析,该模型被暴露在2.45 GHz的可调节的双向微波功率分隔器 (PD) 的直角送天线阵列中.
- 研究了不同功率比率 (0.1到10) 对本地平均MIMO-SAR的影响,考虑了PD微条结构和人体之间的合效应.
- 分析了平均SAR,MIMO通道容量和PD功率比率之间的关系,检查了增加阵列元素的影响.
主要成果:
- 发现局部平均MIMO-SAR依赖于重量函数组合,在一个广泛的可调节功率比率范围 (0.1到10) 中.
- 人体与天线的近距离显著影响了局部平均SAR,这是由于与功率分割器的微条结构的合造成的.
- 增加阵列元件的数量大大降低了平均SAR与MIMO通道容量比率对功率分割器功率比率的依赖.
结论:
- 该研究提供了对影响MIMO-SAR在人体佩戴多天线系统的因素的关键见解.
- 这些发现为设计实现较低SAR值的集成可穿戴天线结构和活性微波电路提供了实际指南.
- 这项研究有助于开发更安全,更高效的移动通信设备和人体区域网络.
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