电小尺寸混合液体天线设计与研究

Water antennas are a new type of antennas which have attracted increasing attentions in recent years. They have attractive features such as: conformable, reconfigurable, transparent, compact size and etc. However, the special electromagnetic characteristic of liquids becomes one of the challenges for liquid antenna designs. In this project, both hybrid liquids and electrically small hybrid liquid antennas are investigated from material and antenna design point of view, new hybrid liquids with wide temperature range and stable electromagnetic characteristics are obtained by mixing different kinds of liquids. The investigations are carried out in terms of theoretical analysis, numerical simulations as well as prototype experiments. Two main research areas are included. The first area focuses on hybrid liquid property characterization. New hybrid liquids are proposed. The permittivity of liquids at various temperatures and substance concentration levels are studied. The nonlinear least-squares fitting routines are employed to derive new formulas for the approximation of the complex permittivity of the liquid. The second area concerns hybrid liquid antenna designs. By using unique features of liquids namely liquidity and transparency, electrically small frequency reconfigurable liquid antennas and compact transparent liquid antennas for hand portable device are designed, simulated, fabricated and measured. Experiments are conducted to qualify and validate the performance of antennas. Finally, liquid antenna designs with good performance are produced for wireless communication systems.

液体天线由于可共形、易重构、透明、尺寸小等优点，近年来受到广泛关注。但液体的特殊电磁特性使得液体天线设计有一定难度。本项目从材料和天线设计交叉学科角度出发，通过混合不同电磁特性的液体，获得电磁性能稳定、可用温度范围宽的混合液体，并基于研制的混合液体，研究电小尺寸混合液体天线的理论和技术。本项目拟从理论分析，数值仿真，模型实验等方面，对混合液体特性和混合液体天线设计进行研究。具体内容包括：1.研制新的混合液体；测试其在不同温度，浓度，频率的介电参数，利用非线性拟合，得出新液体以温度、浓度、频率为变量的多阶介电参数表达式；2.基于新混合液体，充分利用液体的流动性，透明性等优势，结合可重构天线和手机天线技术，设计电小尺寸频率可重构液体天线和用于手持移动终端的紧凑型透明液体天线，获得若干种通过模型实验验证的典型天线结构。最终研发出适用于通信系统的性能优良的液体天线硬件结构。

液体天线由于构造灵活，可重构性强，近年来受到广泛关注。相比于传统金属天线，液体的特殊电磁特性使液体天线设计有一定难度。本项目从液体材料，天线设计以及微流控制交叉学科角度出发，通过研究液体介电参数测试方法和研制不同电磁特性的液体材料，结合液体自身优势，探索液体天线设计的理论和技术。本研究从理论分析，数值仿真，模型实验等方面，对液体天线进行研究。研究内容包括：1.提出基于同轴探针的通用液体材料介电参数测试方法，并获得典型液体样本的介电参数；2.充分利用液体的流动性，透明性等优势，开发了适合液体天线的微流控制系统，设计了高效率宽频带电小尺寸频率可重构液体天线；3.结合电扫寄生天线阵列理论，提出了方向图可重构液体天线设计，实现了可完全隐身、波束指向360°可重构的新型液体天线结构；4.提出了适用于移动终端WiFi应用的透明宽带盐水天线设计，为液体天线设计提供实际工程应用案例。围绕上述研究，本项目还开展了新型离子液体电磁特性研究和混响室液体天线效率测试研究，研发了具有优良电磁特性的新型液体材料和混响室测试方法，确定了一系列研究成果。本项目的研究成果对液体微波器件研发及其应用具有重要意义与应用价值。在项目资助下，共参与发表学术论文17篇，其中SCI收录期刊论文10篇，中文核心期刊论文1篇，EI收录国际会议论文6篇，申请国家发明专利3项, 均已授权。